Integrated Fantastic coffie (decaffeinated) base version

vendor/github.com/ardanlabs/conf/CONTRIBUTORS

@@ -0,0 +1,31 @@
+# This is the official list of people who can contribute
+# (and typically have contributed) code to the gotraining repository.
+#
+# Names should be added to this file only after verifying that
+# the individual or the individual's organization has agreed to
+# the appropriate Contributor License Agreement, found here:
+#
+#     http://code.google.com/legal/individual-cla-v1.0.html
+#     http://code.google.com/legal/corporate-cla-v1.0.html
+#
+# The agreement for individuals can be filled out on the web.
+
+# Names should be added to this file like so:
+#     Name <email address>
+#
+# An entry with two email addresses specifies that the
+# first address should be used in the submit logs and
+# that the second address should be recognized as the
+# same person when interacting with Rietveld.
+
+# Please keep the list sorted.
+
+Arash Bina <arash@arash.io>
+Andy Walker
+Bruno Pereira <brunopereir4@gmail.com>
+Enrico204 <enrico204@gmail.com>
+Fábio Correia <fabiodcorreia@gmail.com>
+Kelsey Hightower
+Peter Bourgon
+Steven Edwards <steven@stephenwithav.com>
+William Kennedy <bill@ardanlabs.com>

vendor/github.com/ardanlabs/conf/LICENSE

@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
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+       http://www.apache.org/licenses/LICENSE-2.0
+
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+   limitations under the License.

vendor/github.com/ardanlabs/conf/README.md

@@ -0,0 +1,29 @@
+# Conf
+
+[![CircleCI](https://circleci.com/gh/ardanlabs/conf.svg?style=svg)](https://circleci.com/gh/ardanlabs/conf)
+
+Copyright 2018, 2019, 2020, 2021, Ardan Labs  
+info@ardanlabs.com
+
+## Licensing
+
+```
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+```
+
+## About The Project
+
+Package conf provides support for using environmental variables and command
+line arguments for configuration.
+
+All of the documentation can be found on the [go.dev](https://pkg.go.dev/github.com/ardanlabs/conf?tab=doc) website.

vendor/github.com/ardanlabs/conf/conf.go

@@ -0,0 +1,240 @@
+package conf
+
+import (
+	"errors"
+	"fmt"
+	"net/url"
+	"os"
+	"reflect"
+	"strings"
+)
+
+// ErrInvalidStruct indicates that a configuration struct is not the correct type.
+var ErrInvalidStruct = errors.New("configuration must be a struct pointer")
+
+// A FieldError occurs when an error occurs updating an individual field
+// in the provided struct value.
+type FieldError struct {
+	fieldName string
+	typeName  string
+	value     string
+	err       error
+}
+
+func (err *FieldError) Error() string {
+	return fmt.Sprintf("conf: error assigning to field %s: converting '%s' to type %s. details: %s", err.fieldName, err.value, err.typeName, err.err)
+}
+
+// Sourcer provides the ability to source data from a configuration source.
+// Consider the use of lazy-loading for sourcing large datasets or systems.
+type Sourcer interface {
+
+	// Source takes the field key and attempts to locate that key in its
+	// configuration data. Returns true if found with the value.
+	Source(fld Field) (string, bool)
+}
+
+// Version provides the abitily to add version and description to the application.
+type Version struct {
+	SVN  string
+	Desc string
+}
+
+// ParseOSArgs parses the configuration allowing command line
+// arguments to override settings. Function returns ErrHelpWanted
+// for any information to be provided to the user.
+func ParseOSArgs(prefix string, cfg interface{}) (string, error) {
+	err := Parse(os.Args[1:], prefix, cfg)
+	if err == nil {
+		return "", nil
+	}
+
+	switch err {
+	case ErrHelpWanted:
+		usage, err := Usage(prefix, cfg)
+		if err != nil {
+			return "", fmt.Errorf("generating config usage: %w", err)
+		}
+		return usage, ErrHelpWanted
+
+	case ErrVersionWanted:
+		version, err := VersionString(prefix, cfg)
+		if err != nil {
+			return "", fmt.Errorf("generating config version: %w", err)
+		}
+		return version, ErrHelpWanted
+	}
+
+	return "", fmt.Errorf("parsing config: %w", err)
+}
+
+// Parse parses configuration into the provided struct.
+func Parse(args []string, namespace string, cfgStruct interface{}, sources ...Sourcer) error {
+
+	// Create the flag source.
+	flag, err := newSourceFlag(args)
+	if err != nil {
+		return err
+	}
+
+	// Append default sources to any provided list.
+	sources = append(sources, newSourceEnv(namespace))
+	sources = append(sources, flag)
+
+	// Get the list of fields from the configuration struct to process.
+	fields, err := extractFields(nil, cfgStruct)
+	if err != nil {
+		return err
+	}
+	if len(fields) == 0 {
+		return errors.New("no fields identified in config struct")
+	}
+
+	// Process all fields found in the config struct provided.
+	for _, field := range fields {
+
+		// If the field is supposed to hold the leftover args then copy them in
+		// from the flags source.
+		if field.Field.Type() == argsT {
+			args := reflect.ValueOf(Args(flag.args))
+			field.Field.Set(args)
+			continue
+		}
+
+		// Set any default value into the struct for this field.
+		if field.Options.DefaultVal != "" {
+			if err := processField(field.Options.DefaultVal, field.Field); err != nil {
+				return &FieldError{
+					fieldName: field.Name,
+					typeName:  field.Field.Type().String(),
+					value:     field.Options.DefaultVal,
+					err:       err,
+				}
+			}
+		}
+
+		// Process each field against all sources.
+		var everProvided bool
+		for _, sourcer := range sources {
+			if sourcer == nil {
+				continue
+			}
+
+			value, provided := sourcer.Source(field)
+			if !provided {
+				continue
+			}
+			everProvided = true
+
+			// A value was found so update the struct value with it.
+			if err := processField(value, field.Field); err != nil {
+				return &FieldError{
+					fieldName: field.Name,
+					typeName:  field.Field.Type().String(),
+					value:     value,
+					err:       err,
+				}
+			}
+		}
+
+		// If this key is not provided by any source, check if it was
+		// required to be provided.
+		if !everProvided && field.Options.Required {
+			return fmt.Errorf("required field %s is missing value", field.Name)
+		}
+	}
+
+	return nil
+}
+
+// Usage provides output to display the config usage on the command line.
+func Usage(namespace string, v interface{}) (string, error) {
+	fields, err := extractFields(nil, v)
+	if err != nil {
+		return "", err
+	}
+
+	return fmtUsage(namespace, fields), nil
+}
+
+// VersionString provides output to display the application version and description on the command line.
+func VersionString(namespace string, v interface{}) (string, error) {
+	fields, err := extractFields(nil, v)
+	if err != nil {
+		return "", err
+	}
+
+	var str strings.Builder
+	for i := range fields {
+		if fields[i].Name == versionKey && fields[i].Field.Len() > 0 {
+			str.WriteString("Version: ")
+			str.WriteString(fields[i].Field.String())
+			continue
+		}
+		if fields[i].Name == descKey && fields[i].Field.Len() > 0 {
+			if str.Len() > 0 {
+				str.WriteString("\n")
+			}
+			str.WriteString(fields[i].Field.String())
+			break
+		}
+	}
+	return str.String(), nil
+}
+
+// String returns a stringified version of the provided conf-tagged
+// struct, minus any fields tagged with `noprint`.
+func String(v interface{}) (string, error) {
+	fields, err := extractFields(nil, v)
+	if err != nil {
+		return "", err
+	}
+
+	var s strings.Builder
+	for i, fld := range fields {
+		if fld.Options.Noprint {
+			continue
+		}
+
+		s.WriteString(flagUsage(fld))
+		s.WriteString("=")
+		v := fmt.Sprintf("%v", fld.Field.Interface())
+
+		switch {
+		case fld.Options.Mask:
+			if u, err := url.Parse(v); err == nil {
+				userPass := u.User.String()
+				if userPass != "" {
+					v = strings.Replace(v, userPass, "xxxxxx:xxxxxx", 1)
+					s.WriteString(v)
+					break
+				}
+			}
+			s.WriteString("xxxxxx")
+
+		default:
+			s.WriteString(v)
+		}
+
+		if i < len(fields)-1 {
+			s.WriteString("\n")
+		}
+	}
+
+	return s.String(), nil
+}
+
+// Args holds command line arguments after flags have been parsed.
+type Args []string
+
+// argsT is used by Parse and Usage to detect struct fields of the Args type.
+var argsT = reflect.TypeOf(Args{})
+
+// Num returns the i'th argument in the Args slice. It returns an empty string
+// the request element is not present.
+func (a Args) Num(i int) string {
+	if i < 0 || i >= len(a) {
+		return ""
+	}
+	return a[i]
+}

vendor/github.com/ardanlabs/conf/doc.go

@@ -0,0 +1,128 @@
+/*
+Package conf provides support for using environmental variables and command
+line arguments for configuration.
+
+It is compatible with the GNU extensions to the POSIX recommendations
+for command-line options. See
+http://www.gnu.org/software/libc/manual/html_node/Argument-Syntax.html
+
+There are no hard bindings for this package. This package takes a struct
+value and parses it for both the environment and flags. It supports several tags
+to customize the flag options.
+
+	default  - Provides the default value for the help
+	env      - Allows for overriding the default variable name.
+	flag     - Allows for overriding the default flag name.
+	short    - Denotes a shorthand option for the flag.
+	noprint  - Denotes to not include the field in any display string.
+	mask     - Includes the field in any display string but masks out the value.
+	required - Denotes a value must be provided.
+	help     - Provides a description for the help.
+
+The field name and any parent struct name will be used for the long form of
+the command name unless the name is overridden.
+
+As an example, this config struct:
+
+	type ip struct {
+		Name string `conf:"default:localhost,env:IP_NAME_VAR"`
+		IP   string `conf:"default:127.0.0.0"`
+	}
+	type Embed struct {
+		Name     string        `conf:"default:bill"`
+		Duration time.Duration `conf:"default:1s,flag:e-dur,short:d"`
+	}
+	type config struct {
+		AnInt   int    `conf:"default:9"`
+		AString string `conf:"default:B,short:s"`
+		Bool    bool
+		Skip    string `conf:"-"`
+		IP      ip
+		Embed
+	}
+
+Would produce the following usage output:
+
+Usage: conf.test [options] [arguments]
+
+OPTIONS
+  --an-int/$CRUD_AN_INT         <int>       (default: 9)
+  --a-string/-s/$CRUD_A_STRING  <string>    (default: B)
+  --bool/$CRUD_BOOL             <bool>
+  --ip-name/$CRUD_IP_NAME_VAR   <string>    (default: localhost)
+  --ip-ip/$CRUD_IP_IP           <string>    (default: 127.0.0.0)
+  --name/$CRUD_NAME             <string>    (default: bill)
+  --e-dur/-d/$CRUD_DURATION     <duration>  (default: 1s)
+  --help/-h
+  display this help message
+  --version/-v
+  display version information
+
+The API is a single call to Parse
+
+	// Parse(args []string, namespace string, cfgStruct interface{}, sources ...Sourcer) error
+
+	if err := conf.Parse(os.Args, "CRUD", &cfg); err != nil {
+		log.Fatalf("main : Parsing Config : %v", err)
+	}
+
+Additionally, if the config struct has a field of the slice type conf.Args
+then it will be populated with any remaining arguments from the command line
+after flags have been processed.
+
+For example a program with a config struct like this:
+
+	var cfg struct {
+		Port int
+		Args conf.Args
+	}
+
+If that program is executed from the command line like this:
+
+	$ my-program --port=9000 serve http
+
+Then the cfg.Args field will contain the string values ["serve", "http"].
+The Args type has a method Num for convenient access to these arguments
+such as this:
+
+	arg0 := cfg.Args.Num(0) // "serve"
+	arg1 := cfg.Args.Num(1) // "http"
+	arg2 := cfg.Args.Num(2) // "" empty string: not enough arguments
+
+You can add a version with a description by adding the Version type to
+your config type
+
+	type ConfExplicit struct {
+		Version conf.Version
+		Address string
+	}
+
+	type ConfImplicit struct {
+		conf.Version
+		Address string
+	}
+
+Then you can set these values at run time for display.
+
+	cfg := struct {
+		Version conf.Version
+	}{
+		Version: conf.Version{
+			SVN:  "v1.0.0",
+			Desc: "Service Description",
+		},
+	}
+
+	if err := conf.Parse(os.Args[1:], "APP", &cfg); err != nil {
+		if err == conf.ErrVersionWanted {
+			version, err := conf.VersionString("APP", &cfg)
+			if err != nil {
+				return err
+			}
+			fmt.Println(version)
+			return nil
+		}
+		fmt.Println("parsing config", err)
+	}
+*/
+package conf

vendor/github.com/ardanlabs/conf/fields.go

@@ -0,0 +1,395 @@
+package conf
+
+import (
+	"encoding"
+	"fmt"
+	"reflect"
+	"strconv"
+	"strings"
+	"time"
+	"unicode"
+)
+
+// Field maintains information about a field in the configuration struct.
+type Field struct {
+	Name    string
+	FlagKey []string
+	EnvKey  []string
+	Field   reflect.Value
+	Options FieldOptions
+
+	// Important for flag parsing or any other source where
+	// booleans might be treated specially.
+	BoolField bool
+}
+
+// FieldOptions maintain flag options for a given field.
+type FieldOptions struct {
+	Help          string
+	DefaultVal    string
+	EnvName       string
+	FlagName      string
+	ShortFlagChar rune
+	Noprint       bool
+	Required      bool
+	Mask          bool
+}
+
+// extractFields uses reflection to examine the struct and generate the keys.
+func extractFields(prefix []string, target interface{}) ([]Field, error) {
+	if prefix == nil {
+		prefix = []string{}
+	}
+	s := reflect.ValueOf(target)
+
+	if s.Kind() != reflect.Ptr {
+		return nil, ErrInvalidStruct
+	}
+	s = s.Elem()
+	if s.Kind() != reflect.Struct {
+		return nil, ErrInvalidStruct
+	}
+	targetType := s.Type()
+
+	var fields []Field
+
+	for i := 0; i < s.NumField(); i++ {
+		f := s.Field(i)
+		structField := targetType.Field(i)
+
+		// Get the conf tags associated with this item (if any).
+		fieldTags := structField.Tag.Get("conf")
+
+		// If it's ignored or can't be set, move on.
+		if !f.CanSet() || fieldTags == "-" {
+			continue
+		}
+
+		fieldName := structField.Name
+
+		// Get and options.  TODO: Need more.
+		fieldOpts, err := parseTag(fieldTags)
+		if err != nil {
+			return nil, fmt.Errorf("conf: error parsing tags for field %s: %s", fieldName, err)
+		}
+
+		// Generate the field key. This could be ignored.
+		fieldKey := append(prefix, camelSplit(fieldName)...)
+
+		// Drill down through pointers until we bottom out at type or nil.
+		for f.Kind() == reflect.Ptr {
+			if f.IsNil() {
+
+				// It's not a struct so leave it alone.
+				if f.Type().Elem().Kind() != reflect.Struct {
+					break
+				}
+
+				// It is a struct so zero it out.
+				f.Set(reflect.New(f.Type().Elem()))
+			}
+			f = f.Elem()
+		}
+
+		switch {
+
+		// If we've found a struct, drill down, appending fields as we go.
+		case f.Kind() == reflect.Struct:
+
+			// Skip if it can deserialize itself.
+			if setterFrom(f) == nil && textUnmarshaler(f) == nil && binaryUnmarshaler(f) == nil {
+
+				// Prefix for any subkeys is the fieldKey, unless it's
+				// anonymous, then it's just the prefix so far.
+				innerPrefix := fieldKey
+				if structField.Anonymous {
+					innerPrefix = prefix
+				}
+
+				embeddedPtr := f.Addr().Interface()
+				innerFields, err := extractFields(innerPrefix, embeddedPtr)
+				if err != nil {
+					return nil, err
+				}
+				fields = append(fields, innerFields...)
+			}
+		default:
+			envKey := fieldKey
+			if fieldOpts.EnvName != "" {
+				envKey = strings.Split(fieldOpts.EnvName, "_")
+			}
+
+			flagKey := fieldKey
+			if fieldOpts.FlagName != "" {
+				flagKey = strings.Split(fieldOpts.FlagName, "-")
+			}
+
+			fld := Field{
+				Name:      fieldName,
+				EnvKey:    envKey,
+				FlagKey:   flagKey,
+				Field:     f,
+				Options:   fieldOpts,
+				BoolField: f.Kind() == reflect.Bool,
+			}
+			fields = append(fields, fld)
+		}
+	}
+
+	return fields, nil
+}
+
+func parseTag(tagStr string) (FieldOptions, error) {
+	var f FieldOptions
+	if tagStr == "" {
+		return f, nil
+	}
+
+	tagParts := strings.Split(tagStr, ",")
+	for _, tagPart := range tagParts {
+		vals := strings.SplitN(tagPart, ":", 2)
+		tagProp := vals[0]
+
+		switch len(vals) {
+		case 1:
+			switch tagProp {
+			case "noprint":
+				f.Noprint = true
+			case "required":
+				f.Required = true
+			case "mask":
+				f.Mask = true
+			}
+		case 2:
+			tagPropVal := strings.TrimSpace(vals[1])
+			if tagPropVal == "" {
+				return f, fmt.Errorf("tag %q missing a value", tagProp)
+			}
+			switch tagProp {
+			case "short":
+				if len([]rune(tagPropVal)) != 1 {
+					return f, fmt.Errorf("short value must be a single rune, got %q", tagPropVal)
+				}
+				f.ShortFlagChar = []rune(tagPropVal)[0]
+			case "default":
+				f.DefaultVal = tagPropVal
+			case "env":
+				f.EnvName = tagPropVal
+			case "flag":
+				f.FlagName = tagPropVal
+			case "help":
+				f.Help = tagPropVal
+			}
+		default:
+			// TODO: Do we check for integrity issues here?
+		}
+	}
+
+	// Perform a sanity check.
+	switch {
+	case f.Required && f.DefaultVal != "":
+		return f, fmt.Errorf("cannot set both `required` and `default`")
+	}
+
+	return f, nil
+}
+
+// camelSplit takes a string based on camel case and splits it.
+func camelSplit(src string) []string {
+	if src == "" {
+		return []string{}
+	}
+	if len(src) < 2 {
+		return []string{src}
+	}
+
+	runes := []rune(src)
+
+	lastClass := charClass(runes[0])
+	lastIdx := 0
+	out := []string{}
+
+	// Split into fields based on class of unicode character.
+	for i, r := range runes {
+		class := charClass(r)
+
+		// If the class has transitioned.
+		if class != lastClass {
+
+			// If going from uppercase to lowercase, we want to retain the last
+			// uppercase letter for names like FOOBar, which should split to
+			// FOO Bar.
+			switch {
+			case lastClass == classUpper && class != classNumber:
+				if i-lastIdx > 1 {
+					out = append(out, string(runes[lastIdx:i-1]))
+					lastIdx = i - 1
+				}
+			default:
+				out = append(out, string(runes[lastIdx:i]))
+				lastIdx = i
+			}
+		}
+
+		if i == len(runes)-1 {
+			out = append(out, string(runes[lastIdx:]))
+		}
+		lastClass = class
+	}
+
+	return out
+}
+
+func processField(value string, field reflect.Value) error {
+	typ := field.Type()
+
+	// Look for a Set method.
+	setter := setterFrom(field)
+	if setter != nil {
+		return setter.Set(value)
+	}
+
+	if t := textUnmarshaler(field); t != nil {
+		return t.UnmarshalText([]byte(value))
+	}
+
+	if b := binaryUnmarshaler(field); b != nil {
+		return b.UnmarshalBinary([]byte(value))
+	}
+
+	if typ.Kind() == reflect.Ptr {
+		typ = typ.Elem()
+		if field.IsNil() {
+			field.Set(reflect.New(typ))
+		}
+		field = field.Elem()
+	}
+
+	switch typ.Kind() {
+	case reflect.String:
+		field.SetString(value)
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		var (
+			val int64
+			err error
+		)
+		if field.Kind() == reflect.Int64 && typ.PkgPath() == "time" && typ.Name() == "Duration" {
+			var d time.Duration
+			d, err = time.ParseDuration(value)
+			val = int64(d)
+		} else {
+			val, err = strconv.ParseInt(value, 0, typ.Bits())
+		}
+		if err != nil {
+			return err
+		}
+
+		field.SetInt(val)
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+		val, err := strconv.ParseUint(value, 0, typ.Bits())
+		if err != nil {
+			return err
+		}
+		field.SetUint(val)
+	case reflect.Bool:
+		val, err := strconv.ParseBool(value)
+		if err != nil {
+			return err
+		}
+		field.SetBool(val)
+	case reflect.Float32, reflect.Float64:
+		val, err := strconv.ParseFloat(value, typ.Bits())
+		if err != nil {
+			return err
+		}
+		field.SetFloat(val)
+	case reflect.Slice:
+		vals := strings.Split(value, ";")
+		sl := reflect.MakeSlice(typ, len(vals), len(vals))
+		for i, val := range vals {
+			err := processField(val, sl.Index(i))
+			if err != nil {
+				return err
+			}
+		}
+		field.Set(sl)
+	case reflect.Map:
+		mp := reflect.MakeMap(typ)
+		if len(strings.TrimSpace(value)) != 0 {
+			pairs := strings.Split(value, ";")
+			for _, pair := range pairs {
+				kvpair := strings.Split(pair, ":")
+				if len(kvpair) != 2 {
+					return fmt.Errorf("invalid map item: %q", pair)
+				}
+				k := reflect.New(typ.Key()).Elem()
+				err := processField(kvpair[0], k)
+				if err != nil {
+					return err
+				}
+				v := reflect.New(typ.Elem()).Elem()
+				err = processField(kvpair[1], v)
+				if err != nil {
+					return err
+				}
+				mp.SetMapIndex(k, v)
+			}
+		}
+		field.Set(mp)
+	}
+	return nil
+}
+
+func interfaceFrom(field reflect.Value, fn func(interface{}, *bool)) {
+
+	// It may be impossible for a struct field to fail this check.
+	if !field.CanInterface() {
+		return
+	}
+
+	var ok bool
+	fn(field.Interface(), &ok)
+	if !ok && field.CanAddr() {
+		fn(field.Addr().Interface(), &ok)
+	}
+}
+
+// Setter is implemented by types can self-deserialize values.
+// Any type that implements flag.Value also implements Setter.
+type Setter interface {
+	Set(value string) error
+}
+
+func setterFrom(field reflect.Value) (s Setter) {
+	interfaceFrom(field, func(v interface{}, ok *bool) { s, *ok = v.(Setter) })
+	return s
+}
+
+func textUnmarshaler(field reflect.Value) (t encoding.TextUnmarshaler) {
+	interfaceFrom(field, func(v interface{}, ok *bool) { t, *ok = v.(encoding.TextUnmarshaler) })
+	return t
+}
+
+func binaryUnmarshaler(field reflect.Value) (b encoding.BinaryUnmarshaler) {
+	interfaceFrom(field, func(v interface{}, ok *bool) { b, *ok = v.(encoding.BinaryUnmarshaler) })
+	return b
+}
+
+const (
+	classLower int = iota
+	classUpper
+	classNumber
+	classOther
+)
+
+func charClass(r rune) int {
+	switch {
+	case unicode.IsLower(r):
+		return classLower
+	case unicode.IsUpper(r):
+		return classUpper
+	case unicode.IsDigit(r):
+		return classNumber
+	}
+	return classOther
+}

vendor/github.com/ardanlabs/conf/sources.go

@@ -0,0 +1,205 @@
+package conf
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"strings"
+)
+
+// env is a source for environmental variables.
+type env struct {
+	m map[string]string
+}
+
+// newSourceEnv accepts a namespace and parses the environment into a Env for
+// use by the configuration package.
+func newSourceEnv(namespace string) *env {
+	m := make(map[string]string)
+
+	// Create the uppercase version to meet the standard {NAMESPACE_} format.
+	// If the namespace is empty, remove the _ from the beginning of the string.
+	uspace := fmt.Sprintf("%s_", strings.ToUpper(namespace))
+	if namespace == "" {
+		uspace = uspace[1:]
+	}
+
+	// Loop and match each variable using the uppercase namespace.
+	for _, val := range os.Environ() {
+		if !strings.HasPrefix(val, uspace) {
+			continue
+		}
+
+		idx := strings.Index(val, "=")
+		m[strings.ToUpper(strings.TrimPrefix(val[0:idx], uspace))] = val[idx+1:]
+	}
+
+	return &env{m: m}
+}
+
+// Source implements the confg.Sourcer interface. It returns the stringfied value
+// stored at the specified key from the environment.
+func (e *env) Source(fld Field) (string, bool) {
+	k := strings.ToUpper(strings.Join(fld.EnvKey, `_`))
+	v, ok := e.m[k]
+	return v, ok
+}
+
+// envUsage constructs a usage string for the environment variable.
+func envUsage(namespace string, fld Field) string {
+	uspace := strings.ToUpper(namespace) + "_" + strings.ToUpper(strings.Join(fld.EnvKey, `_`))
+	if namespace == "" {
+		uspace = uspace[1:]
+	}
+	return "$" + uspace
+}
+
+// =============================================================================
+
+// ErrHelpWanted provides an indication help was requested.
+var ErrHelpWanted = errors.New("help wanted")
+
+// ErrVersionWanted provides an indication version was requested.
+var ErrVersionWanted = errors.New("version wanted")
+
+// flag is a source for command line arguments.
+type flag struct {
+	m    map[string]string
+	args []string
+}
+
+// newSourceFlag parsing a string of command line arguments. NewFlag will return
+// errHelpWanted, if the help flag is identifyed. This code is adapted
+// from the Go standard library flag package.
+func newSourceFlag(args []string) (*flag, error) {
+	m := make(map[string]string)
+
+	if len(args) != 0 {
+		for {
+			if len(args) == 0 {
+				break
+			}
+
+			// Look at the next arg.
+			s := args[0]
+
+			// If it's too short or doesn't begin with a `-`, assume we're at
+			// the end of the flags.
+			if len(s) < 2 || s[0] != '-' {
+				break
+			}
+
+			numMinuses := 1
+			if s[1] == '-' {
+				numMinuses++
+				if len(s) == 2 { // "--" terminates the flags
+					args = args[1:]
+					break
+				}
+			}
+
+			name := s[numMinuses:]
+			if len(name) == 0 || name[0] == '-' || name[0] == '=' {
+				return nil, fmt.Errorf("bad flag syntax: %s", s)
+			}
+
+			// It's a flag. Does it have an argument?
+			args = args[1:]
+			hasValue := false
+			value := ""
+			for i := 1; i < len(name); i++ { // equals cannot be first
+				if name[i] == '=' {
+					value = name[i+1:]
+					hasValue = true
+					name = name[0:i]
+					break
+				}
+			}
+
+			if name == "help" || name == "h" || name == "?" {
+				return nil, ErrHelpWanted
+			}
+
+			if name == "version" || name == "v" {
+				return nil, ErrVersionWanted
+			}
+
+			// If we don't have a value yet, it's possible the flag was not in the
+			// -flag=value format which means it might still have a value which would be
+			// the next argument, provided the next argument isn't a flag.
+			if !hasValue {
+				if len(args) > 0 && len(args[0]) > 0 && args[0][0] != '-' {
+
+					// Doesn't look like a flag. Must be a value.
+					value, args = args[0], args[1:]
+				} else {
+
+					// We assume this is a boolean flag.
+					value = "true"
+				}
+			}
+
+			// Store the flag/value pair.
+			m[name] = value
+		}
+	}
+
+	return &flag{m: m, args: args}, nil
+}
+
+// Source implements the confg.Sourcer interface. Returns the stringfied value
+// stored at the specified key from the flag source.
+func (f *flag) Source(fld Field) (string, bool) {
+	if fld.Options.ShortFlagChar != 0 {
+		flagKey := fld.Options.ShortFlagChar
+		k := strings.ToLower(string(flagKey))
+		if val, found := f.m[k]; found {
+			return val, found
+		}
+	}
+
+	k := strings.ToLower(strings.Join(fld.FlagKey, `-`))
+	val, found := f.m[k]
+	return val, found
+}
+
+// flagUsage constructs a usage string for the flag argument.
+func flagUsage(fld Field) string {
+	usage := "--" + strings.ToLower(strings.Join(fld.FlagKey, `-`))
+	if fld.Options.ShortFlagChar != 0 {
+		flagKey := []string{string(fld.Options.ShortFlagChar)}
+		usage += "/-" + strings.ToLower(strings.Join(flagKey, `-`))
+	}
+
+	return usage
+}
+
+/*
+Portions Copyright (c) 2009 The Go Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/

vendor/github.com/ardanlabs/conf/usage.go

@@ -0,0 +1,184 @@
+package conf
+
+import (
+	"fmt"
+	"os"
+	"path"
+	"reflect"
+	"strings"
+	"text/tabwriter"
+)
+
+const versionKey = `SVN`
+const descKey = `Desc`
+
+func containsField(fields []Field, name string) bool {
+	for i := range fields {
+		if name == fields[i].Name {
+			return true
+		}
+	}
+	return false
+}
+
+func fmtUsage(namespace string, fields []Field) string {
+	var sb strings.Builder
+
+	fields = append(fields, Field{
+		Name:      "help",
+		BoolField: true,
+		Field:     reflect.ValueOf(true),
+		FlagKey:   []string{"help"},
+		Options: FieldOptions{
+			ShortFlagChar: 'h',
+			Help:          "display this help message",
+		}})
+
+	if containsField(fields, versionKey) {
+		fields = append(fields, Field{
+			Name:      "version",
+			BoolField: true,
+			Field:     reflect.ValueOf(true),
+			FlagKey:   []string{"version"},
+			Options: FieldOptions{
+				ShortFlagChar: 'v',
+				Help:          "display version information",
+			}})
+	}
+
+	_, file := path.Split(os.Args[0])
+	fmt.Fprintf(&sb, "Usage: %s [options] [arguments]\n\n", file)
+
+	fmt.Fprintln(&sb, "OPTIONS")
+	w := new(tabwriter.Writer)
+	w.Init(&sb, 0, 4, 2, ' ', tabwriter.TabIndent)
+
+	for _, fld := range fields {
+
+		// Skip printing usage info for fields that just hold arguments.
+		if fld.Field.Type() == argsT {
+			continue
+		}
+
+		// Do not display version fields SVN and Description
+		if fld.Name == versionKey || fld.Name == descKey {
+			continue
+		}
+
+		fmt.Fprintf(w, "  %s", flagUsage(fld))
+
+		// Do not display env vars for help since they aren't respected.
+		if fld.Name != "help" && fld.Name != "version" {
+			fmt.Fprintf(w, "/%s", envUsage(namespace, fld))
+		}
+
+		typeName, help := getTypeAndHelp(&fld)
+
+		// Do not display type info for help because it would show <bool> but our
+		// parsing does not really treat --help as a boolean field. Its presence
+		// always indicates true even if they do --help=false.
+		if fld.Name != "help" && fld.Name != "version" {
+			fmt.Fprintf(w, "\t%s", typeName)
+		}
+
+		fmt.Fprintf(w, "\t%s\n", getOptString(fld))
+		if help != "" {
+			fmt.Fprintf(w, "  %s\n", help)
+		}
+	}
+
+	w.Flush()
+	return sb.String()
+}
+
+// getTypeAndHelp extracts the type and help message for a single field for
+// printing in the usage message. If the help message contains text in
+// single quotes ('), this is assumed to be a more specific "type", and will
+// be returned as such. If there are no back quotes, it attempts to make a
+// guess as to the type of the field. Boolean flags are not printed with a
+// type, manually-specified or not, since their presence is equated with a
+// 'true' value and their absence with a 'false' value. If a type cannot be
+// determined, it will simply give the name "value". Slices will be annotated
+// as "<Type>,[Type...]", where "Type" is whatever type name was chosen.
+// (adapted from package flag).
+func getTypeAndHelp(fld *Field) (name string, usage string) {
+
+	// Look for a single-quoted name.
+	usage = fld.Options.Help
+	for i := 0; i < len(usage); i++ {
+		if usage[i] == '\'' {
+			for j := i + 1; j < len(usage); j++ {
+				if usage[j] == '\'' {
+					name = usage[i+1 : j]
+					usage = usage[:i] + name + usage[j+1:]
+				}
+			}
+			break // Only one single quote; use type name.
+		}
+	}
+
+	var isSlice bool
+	if fld.Field.IsValid() {
+		t := fld.Field.Type()
+
+		// If it's a pointer, we want to deref.
+		if t.Kind() == reflect.Ptr {
+			t = t.Elem()
+		}
+
+		// If it's a slice, we want the type of the slice elements.
+		if t.Kind() == reflect.Slice {
+			t = t.Elem()
+			isSlice = true
+		}
+
+		// If no explicit name was provided, attempt to get the type
+		if name == "" {
+			switch t.Kind() {
+			case reflect.Bool:
+				name = "bool"
+			case reflect.Float32, reflect.Float64:
+				name = "float"
+			case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+				typ := fld.Field.Type()
+				if typ.PkgPath() == "time" && typ.Name() == "Duration" {
+					name = "duration"
+				} else {
+					name = "int"
+				}
+			case reflect.String:
+				name = "string"
+			case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+				name = "uint"
+			default:
+				name = "value"
+			}
+		}
+	}
+
+	switch {
+	case isSlice:
+		name = fmt.Sprintf("<%s>,[%s...]", name, name)
+	case name != "":
+		name = fmt.Sprintf("<%s>", name)
+	default:
+	}
+	return
+}
+
+func getOptString(fld Field) string {
+	opts := make([]string, 0, 3)
+	if fld.Options.Required {
+		opts = append(opts, "required")
+	}
+	if fld.Options.Noprint {
+		opts = append(opts, "noprint")
+	}
+	if fld.Options.DefaultVal != "" {
+		opts = append(opts, fmt.Sprintf("default: %s", fld.Options.DefaultVal))
+	}
+	if len(opts) > 0 {
+		return fmt.Sprintf("(%s)", strings.Join(opts, `,`))
+	}
+	return ""
+}

vendor/github.com/felixge/httpsnoop/.travis.yml

@@ -0,0 +1,6 @@
+language: go
+
+go:
+  - 1.6
+  - 1.7
+  - 1.8

vendor/github.com/felixge/httpsnoop/LICENSE.txt

@@ -0,0 +1,19 @@
+Copyright (c) 2016 Felix Geisendörfer (felix@debuggable.com)
+
+ Permission is hereby granted, free of charge, to any person obtaining a copy
+ of this software and associated documentation files (the "Software"), to deal
+ in the Software without restriction, including without limitation the rights
+ to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ copies of the Software, and to permit persons to whom the Software is
+ furnished to do so, subject to the following conditions:
+
+ The above copyright notice and this permission notice shall be included in
+ all copies or substantial portions of the Software.
+
+ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ THE SOFTWARE.

vendor/github.com/felixge/httpsnoop/Makefile

@@ -0,0 +1,10 @@
+.PHONY: ci generate clean
+
+ci: clean generate
+	go test -v ./...
+
+generate:
+	go generate .
+
+clean:
+	rm -rf *_generated*.go

vendor/github.com/felixge/httpsnoop/README.md

@@ -0,0 +1,94 @@
+# httpsnoop
+
+Package httpsnoop provides an easy way to capture http related metrics (i.e.
+response time, bytes written, and http status code) from your application's
+http.Handlers.
+
+Doing this requires non-trivial wrapping of the http.ResponseWriter interface,
+which is also exposed for users interested in a more low-level API.
+
+[![GoDoc](https://godoc.org/github.com/felixge/httpsnoop?status.svg)](https://godoc.org/github.com/felixge/httpsnoop)
+[![Build Status](https://travis-ci.org/felixge/httpsnoop.svg?branch=master)](https://travis-ci.org/felixge/httpsnoop)
+
+## Usage Example
+
+```go
+// myH is your app's http handler, perhaps a http.ServeMux or similar.
+var myH http.Handler
+// wrappedH wraps myH in order to log every request.
+wrappedH := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+	m := httpsnoop.CaptureMetrics(myH, w, r)
+	log.Printf(
+		"%s %s (code=%d dt=%s written=%d)",
+		r.Method,
+		r.URL,
+		m.Code,
+		m.Duration,
+		m.Written,
+	)
+})
+http.ListenAndServe(":8080", wrappedH)
+```
+
+## Why this package exists
+
+Instrumenting an application's http.Handler is surprisingly difficult.
+
+However if you google for e.g. "capture ResponseWriter status code" you'll find
+lots of advise and code examples that suggest it to be a fairly trivial
+undertaking. Unfortunately everything I've seen so far has a high chance of
+breaking your application.
+
+The main problem is that a `http.ResponseWriter` often implements additional
+interfaces such as `http.Flusher`, `http.CloseNotifier`, `http.Hijacker`, `http.Pusher`, and
+`io.ReaderFrom`. So the naive approach of just wrapping `http.ResponseWriter`
+in your own struct that also implements the `http.ResponseWriter` interface
+will hide the additional interfaces mentioned above. This has a high change of
+introducing subtle bugs into any non-trivial application.
+
+Another approach I've seen people take is to return a struct that implements
+all of the interfaces above. However, that's also problematic, because it's
+difficult to fake some of these interfaces behaviors when the underlying
+`http.ResponseWriter` doesn't have an implementation. It's also dangerous,
+because an application may choose to operate differently, merely because it
+detects the presence of these additional interfaces.
+
+This package solves this problem by checking which additional interfaces a
+`http.ResponseWriter` implements, returning a wrapped version implementing the
+exact same set of interfaces.
+
+Additionally this package properly handles edge cases such as `WriteHeader` not
+being called, or called more than once, as well as concurrent calls to
+`http.ResponseWriter` methods, and even calls happening after the wrapped
+`ServeHTTP` has already returned.
+
+Unfortunately this package is not perfect either. It's possible that it is
+still missing some interfaces provided by the go core (let me know if you find
+one), and it won't work for applications adding their own interfaces into the
+mix.
+
+However, hopefully the explanation above has sufficiently scared you of rolling
+your own solution to this problem. httpsnoop may still break your application,
+but at least it tries to avoid it as much as possible.
+
+Anyway, the real problem here is that smuggling additional interfaces inside
+`http.ResponseWriter` is a problematic design choice, but it probably goes as
+deep as the Go language specification itself. But that's okay, I still prefer
+Go over the alternatives ;).
+
+## Performance
+
+```
+BenchmarkBaseline-8      	   20000	     94912 ns/op
+BenchmarkCaptureMetrics-8	   20000	     95461 ns/op
+```
+
+As you can see, using `CaptureMetrics` on a vanilla http.Handler introduces an
+overhead of ~500 ns per http request on my machine. However, the margin of
+error appears to be larger than that, therefor it should be reasonable to
+assume that the overhead introduced by `CaptureMetrics` is absolutely
+negligible.
+
+## License
+
+MIT

vendor/github.com/felixge/httpsnoop/capture_metrics.go

@@ -0,0 +1,84 @@
+package httpsnoop
+
+import (
+	"io"
+	"net/http"
+	"sync"
+	"time"
+)
+
+// Metrics holds metrics captured from CaptureMetrics.
+type Metrics struct {
+	// Code is the first http response code passed to the WriteHeader func of
+	// the ResponseWriter. If no such call is made, a default code of 200 is
+	// assumed instead.
+	Code int
+	// Duration is the time it took to execute the handler.
+	Duration time.Duration
+	// Written is the number of bytes successfully written by the Write or
+	// ReadFrom function of the ResponseWriter. ResponseWriters may also write
+	// data to their underlaying connection directly (e.g. headers), but those
+	// are not tracked. Therefor the number of Written bytes will usually match
+	// the size of the response body.
+	Written int64
+}
+
+// CaptureMetrics wraps the given hnd, executes it with the given w and r, and
+// returns the metrics it captured from it.
+func CaptureMetrics(hnd http.Handler, w http.ResponseWriter, r *http.Request) Metrics {
+	return CaptureMetricsFn(w, func(ww http.ResponseWriter) {
+		hnd.ServeHTTP(ww, r)
+	})
+}
+
+// CaptureMetricsFn wraps w and calls fn with the wrapped w and returns the
+// resulting metrics. This is very similar to CaptureMetrics (which is just
+// sugar on top of this func), but is a more usable interface if your
+// application doesn't use the Go http.Handler interface.
+func CaptureMetricsFn(w http.ResponseWriter, fn func(http.ResponseWriter)) Metrics {
+	var (
+		start         = time.Now()
+		m             = Metrics{Code: http.StatusOK}
+		headerWritten bool
+		lock          sync.Mutex
+		hooks         = Hooks{
+			WriteHeader: func(next WriteHeaderFunc) WriteHeaderFunc {
+				return func(code int) {
+					next(code)
+					lock.Lock()
+					defer lock.Unlock()
+					if !headerWritten {
+						m.Code = code
+						headerWritten = true
+					}
+				}
+			},
+
+			Write: func(next WriteFunc) WriteFunc {
+				return func(p []byte) (int, error) {
+					n, err := next(p)
+					lock.Lock()
+					defer lock.Unlock()
+					m.Written += int64(n)
+					headerWritten = true
+					return n, err
+				}
+			},
+
+			ReadFrom: func(next ReadFromFunc) ReadFromFunc {
+				return func(src io.Reader) (int64, error) {
+					n, err := next(src)
+					lock.Lock()
+					defer lock.Unlock()
+					headerWritten = true
+					m.Written += n
+					return n, err
+				}
+			},
+		}
+	)
+
+	fn(Wrap(w, hooks))
+	m.Duration = time.Since(start)
+	return m
+}

vendor/github.com/felixge/httpsnoop/docs.go

@@ -0,0 +1,10 @@
+// Package httpsnoop provides an easy way to capture http related metrics (i.e.
+// response time, bytes written, and http status code) from your application's
+// http.Handlers.
+//
+// Doing this requires non-trivial wrapping of the http.ResponseWriter
+// interface, which is also exposed for users interested in a more low-level
+// API.
+package httpsnoop
+
+//go:generate go run codegen/main.go

vendor/github.com/felixge/httpsnoop/wrap_generated_gteq_1.8.go

@@ -0,0 +1,385 @@
+// +build go1.8
+// Code generated by "httpsnoop/codegen"; DO NOT EDIT
+
+package httpsnoop
+
+import (
+	"bufio"
+	"io"
+	"net"
+	"net/http"
+)
+
+// HeaderFunc is part of the http.ResponseWriter interface.
+type HeaderFunc func() http.Header
+
+// WriteHeaderFunc is part of the http.ResponseWriter interface.
+type WriteHeaderFunc func(code int)
+
+// WriteFunc is part of the http.ResponseWriter interface.
+type WriteFunc func(b []byte) (int, error)
+
+// FlushFunc is part of the http.Flusher interface.
+type FlushFunc func()
+
+// CloseNotifyFunc is part of the http.CloseNotifier interface.
+type CloseNotifyFunc func() <-chan bool
+
+// HijackFunc is part of the http.Hijacker interface.
+type HijackFunc func() (net.Conn, *bufio.ReadWriter, error)
+
+// ReadFromFunc is part of the io.ReaderFrom interface.
+type ReadFromFunc func(src io.Reader) (int64, error)
+
+// PushFunc is part of the http.Pusher interface.
+type PushFunc func(target string, opts *http.PushOptions) error
+
+// Hooks defines a set of method interceptors for methods included in
+// http.ResponseWriter as well as some others. You can think of them as
+// middleware for the function calls they target. See Wrap for more details.
+type Hooks struct {
+	Header      func(HeaderFunc) HeaderFunc
+	WriteHeader func(WriteHeaderFunc) WriteHeaderFunc
+	Write       func(WriteFunc) WriteFunc
+	Flush       func(FlushFunc) FlushFunc
+	CloseNotify func(CloseNotifyFunc) CloseNotifyFunc
+	Hijack      func(HijackFunc) HijackFunc
+	ReadFrom    func(ReadFromFunc) ReadFromFunc
+	Push        func(PushFunc) PushFunc
+}
+
+// Wrap returns a wrapped version of w that provides the exact same interface
+// as w. Specifically if w implements any combination of:
+//
+// - http.Flusher
+// - http.CloseNotifier
+// - http.Hijacker
+// - io.ReaderFrom
+// - http.Pusher
+//
+// The wrapped version will implement the exact same combination. If no hooks
+// are set, the wrapped version also behaves exactly as w. Hooks targeting
+// methods not supported by w are ignored. Any other hooks will intercept the
+// method they target and may modify the call's arguments and/or return values.
+// The CaptureMetrics implementation serves as a working example for how the
+// hooks can be used.
+func Wrap(w http.ResponseWriter, hooks Hooks) http.ResponseWriter {
+	rw := &rw{w: w, h: hooks}
+	_, i0 := w.(http.Flusher)
+	_, i1 := w.(http.CloseNotifier)
+	_, i2 := w.(http.Hijacker)
+	_, i3 := w.(io.ReaderFrom)
+	_, i4 := w.(http.Pusher)
+	switch {
+	// combination 1/32
+	case !i0 && !i1 && !i2 && !i3 && !i4:
+		return struct {
+			http.ResponseWriter
+		}{rw}
+	// combination 2/32
+	case !i0 && !i1 && !i2 && !i3 && i4:
+		return struct {
+			http.ResponseWriter
+			http.Pusher
+		}{rw, rw}
+	// combination 3/32
+	case !i0 && !i1 && !i2 && i3 && !i4:
+		return struct {
+			http.ResponseWriter
+			io.ReaderFrom
+		}{rw, rw}
+	// combination 4/32
+	case !i0 && !i1 && !i2 && i3 && i4:
+		return struct {
+			http.ResponseWriter
+			io.ReaderFrom
+			http.Pusher
+		}{rw, rw, rw}
+	// combination 5/32
+	case !i0 && !i1 && i2 && !i3 && !i4:
+		return struct {
+			http.ResponseWriter
+			http.Hijacker
+		}{rw, rw}
+	// combination 6/32
+	case !i0 && !i1 && i2 && !i3 && i4:
+		return struct {
+			http.ResponseWriter
+			http.Hijacker
+			http.Pusher
+		}{rw, rw, rw}
+	// combination 7/32
+	case !i0 && !i1 && i2 && i3 && !i4:
+		return struct {
+			http.ResponseWriter
+			http.Hijacker
+			io.ReaderFrom
+		}{rw, rw, rw}
+	// combination 8/32
+	case !i0 && !i1 && i2 && i3 && i4:
+		return struct {
+			http.ResponseWriter
+			http.Hijacker
+			io.ReaderFrom
+			http.Pusher
+		}{rw, rw, rw, rw}
+	// combination 9/32
+	case !i0 && i1 && !i2 && !i3 && !i4:
+		return struct {
+			http.ResponseWriter
+			http.CloseNotifier
+		}{rw, rw}
+	// combination 10/32
+	case !i0 && i1 && !i2 && !i3 && i4:
+		return struct {
+			http.ResponseWriter
+			http.CloseNotifier
+			http.Pusher
+		}{rw, rw, rw}
+	// combination 11/32
+	case !i0 && i1 && !i2 && i3 && !i4:
+		return struct {
+			http.ResponseWriter
+			http.CloseNotifier
+			io.ReaderFrom
+		}{rw, rw, rw}
+	// combination 12/32
+	case !i0 && i1 && !i2 && i3 && i4:
+		return struct {
+			http.ResponseWriter
+			http.CloseNotifier
+			io.ReaderFrom
+			http.Pusher
+		}{rw, rw, rw, rw}
+	// combination 13/32
+	case !i0 && i1 && i2 && !i3 && !i4:
+		return struct {
+			http.ResponseWriter
+			http.CloseNotifier
+			http.Hijacker
+		}{rw, rw, rw}
+	// combination 14/32
+	case !i0 && i1 && i2 && !i3 && i4:
+		return struct {
+			http.ResponseWriter
+			http.CloseNotifier
+			http.Hijacker
+			http.Pusher
+		}{rw, rw, rw, rw}
+	// combination 15/32
+	case !i0 && i1 && i2 && i3 && !i4:
+		return struct {
+			http.ResponseWriter
+			http.CloseNotifier
+			http.Hijacker
+			io.ReaderFrom
+		}{rw, rw, rw, rw}
+	// combination 16/32
+	case !i0 && i1 && i2 && i3 && i4:
+		return struct {
+			http.ResponseWriter
+			http.CloseNotifier
+			http.Hijacker
+			io.ReaderFrom
+			http.Pusher
+		}{rw, rw, rw, rw, rw}
+	// combination 17/32
+	case i0 && !i1 && !i2 && !i3 && !i4:
+		return struct {
+			http.ResponseWriter
+			http.Flusher
+		}{rw, rw}
+	// combination 18/32
+	case i0 && !i1 && !i2 && !i3 && i4:
+		return struct {
+			http.ResponseWriter
+			http.Flusher
+			http.Pusher
+		}{rw, rw, rw}
+	// combination 19/32
+	case i0 && !i1 && !i2 && i3 && !i4:
+		return struct {
+			http.ResponseWriter
+			http.Flusher
+			io.ReaderFrom
+		}{rw, rw, rw}
+	// combination 20/32
+	case i0 && !i1 && !i2 && i3 && i4:
+		return struct {
+			http.ResponseWriter
+			http.Flusher
+			io.ReaderFrom
+			http.Pusher
+		}{rw, rw, rw, rw}
+	// combination 21/32
+	case i0 && !i1 && i2 && !i3 && !i4:
+		return struct {
+			http.ResponseWriter
+			http.Flusher
+			http.Hijacker
+		}{rw, rw, rw}
+	// combination 22/32
+	case i0 && !i1 && i2 && !i3 && i4:
+		return struct {
+			http.ResponseWriter
+			http.Flusher
+			http.Hijacker
+			http.Pusher
+		}{rw, rw, rw, rw}
+	// combination 23/32
+	case i0 && !i1 && i2 && i3 && !i4:
+		return struct {
+			http.ResponseWriter
+			http.Flusher
+			http.Hijacker
+			io.ReaderFrom
+		}{rw, rw, rw, rw}
+	// combination 24/32
+	case i0 && !i1 && i2 && i3 && i4:
+		return struct {
+			http.ResponseWriter
+			http.Flusher
+			http.Hijacker
+			io.ReaderFrom
+			http.Pusher
+		}{rw, rw, rw, rw, rw}
+	// combination 25/32
+	case i0 && i1 && !i2 && !i3 && !i4:
+		return struct {
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+		}{rw, rw, rw}
+	// combination 26/32
+	case i0 && i1 && !i2 && !i3 && i4:
+		return struct {
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			http.Pusher
+		}{rw, rw, rw, rw}
+	// combination 27/32
+	case i0 && i1 && !i2 && i3 && !i4:
+		return struct {
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			io.ReaderFrom
+		}{rw, rw, rw, rw}
+	// combination 28/32
+	case i0 && i1 && !i2 && i3 && i4:
+		return struct {
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			io.ReaderFrom
+			http.Pusher
+		}{rw, rw, rw, rw, rw}
+	// combination 29/32
+	case i0 && i1 && i2 && !i3 && !i4:
+		return struct {
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			http.Hijacker
+		}{rw, rw, rw, rw}
+	// combination 30/32
+	case i0 && i1 && i2 && !i3 && i4:
+		return struct {
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			http.Hijacker
+			http.Pusher
+		}{rw, rw, rw, rw, rw}
+	// combination 31/32
+	case i0 && i1 && i2 && i3 && !i4:
+		return struct {
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			http.Hijacker
+			io.ReaderFrom
+		}{rw, rw, rw, rw, rw}
+	// combination 32/32
+	case i0 && i1 && i2 && i3 && i4:
+		return struct {
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			http.Hijacker
+			io.ReaderFrom
+			http.Pusher
+		}{rw, rw, rw, rw, rw, rw}
+	}
+	panic("unreachable")
+}
+
+type rw struct {
+	w http.ResponseWriter
+	h Hooks
+}
+
+func (w *rw) Header() http.Header {
+	f := w.w.(http.ResponseWriter).Header
+	if w.h.Header != nil {
+		f = w.h.Header(f)
+	}
+	return f()
+}
+
+func (w *rw) WriteHeader(code int) {
+	f := w.w.(http.ResponseWriter).WriteHeader
+	if w.h.WriteHeader != nil {
+		f = w.h.WriteHeader(f)
+	}
+	f(code)
+}
+
+func (w *rw) Write(b []byte) (int, error) {
+	f := w.w.(http.ResponseWriter).Write
+	if w.h.Write != nil {
+		f = w.h.Write(f)
+	}
+	return f(b)
+}
+
+func (w *rw) Flush() {
+	f := w.w.(http.Flusher).Flush
+	if w.h.Flush != nil {
+		f = w.h.Flush(f)
+	}
+	f()
+}
+
+func (w *rw) CloseNotify() <-chan bool {
+	f := w.w.(http.CloseNotifier).CloseNotify
+	if w.h.CloseNotify != nil {
+		f = w.h.CloseNotify(f)
+	}
+	return f()
+}
+
+func (w *rw) Hijack() (net.Conn, *bufio.ReadWriter, error) {
+	f := w.w.(http.Hijacker).Hijack
+	if w.h.Hijack != nil {
+		f = w.h.Hijack(f)
+	}
+	return f()
+}
+
+func (w *rw) ReadFrom(src io.Reader) (int64, error) {
+	f := w.w.(io.ReaderFrom).ReadFrom
+	if w.h.ReadFrom != nil {
+		f = w.h.ReadFrom(f)
+	}
+	return f(src)
+}
+
+func (w *rw) Push(target string, opts *http.PushOptions) error {
+	f := w.w.(http.Pusher).Push
+	if w.h.Push != nil {
+		f = w.h.Push(f)
+	}
+	return f(target, opts)
+}

vendor/github.com/felixge/httpsnoop/wrap_generated_lt_1.8.go

@@ -0,0 +1,243 @@
+// +build !go1.8
+// Code generated by "httpsnoop/codegen"; DO NOT EDIT
+
+package httpsnoop
+
+import (
+	"bufio"
+	"io"
+	"net"
+	"net/http"
+)
+
+// HeaderFunc is part of the http.ResponseWriter interface.
+type HeaderFunc func() http.Header
+
+// WriteHeaderFunc is part of the http.ResponseWriter interface.
+type WriteHeaderFunc func(code int)
+
+// WriteFunc is part of the http.ResponseWriter interface.
+type WriteFunc func(b []byte) (int, error)
+
+// FlushFunc is part of the http.Flusher interface.
+type FlushFunc func()
+
+// CloseNotifyFunc is part of the http.CloseNotifier interface.
+type CloseNotifyFunc func() <-chan bool
+
+// HijackFunc is part of the http.Hijacker interface.
+type HijackFunc func() (net.Conn, *bufio.ReadWriter, error)
+
+// ReadFromFunc is part of the io.ReaderFrom interface.
+type ReadFromFunc func(src io.Reader) (int64, error)
+
+// Hooks defines a set of method interceptors for methods included in
+// http.ResponseWriter as well as some others. You can think of them as
+// middleware for the function calls they target. See Wrap for more details.
+type Hooks struct {
+	Header      func(HeaderFunc) HeaderFunc
+	WriteHeader func(WriteHeaderFunc) WriteHeaderFunc
+	Write       func(WriteFunc) WriteFunc
+	Flush       func(FlushFunc) FlushFunc
+	CloseNotify func(CloseNotifyFunc) CloseNotifyFunc
+	Hijack      func(HijackFunc) HijackFunc
+	ReadFrom    func(ReadFromFunc) ReadFromFunc
+}
+
+// Wrap returns a wrapped version of w that provides the exact same interface
+// as w. Specifically if w implements any combination of:
+//
+// - http.Flusher
+// - http.CloseNotifier
+// - http.Hijacker
+// - io.ReaderFrom
+//
+// The wrapped version will implement the exact same combination. If no hooks
+// are set, the wrapped version also behaves exactly as w. Hooks targeting
+// methods not supported by w are ignored. Any other hooks will intercept the
+// method they target and may modify the call's arguments and/or return values.
+// The CaptureMetrics implementation serves as a working example for how the
+// hooks can be used.
+func Wrap(w http.ResponseWriter, hooks Hooks) http.ResponseWriter {
+	rw := &rw{w: w, h: hooks}
+	_, i0 := w.(http.Flusher)
+	_, i1 := w.(http.CloseNotifier)
+	_, i2 := w.(http.Hijacker)
+	_, i3 := w.(io.ReaderFrom)
+	switch {
+	// combination 1/16
+	case !i0 && !i1 && !i2 && !i3:
+		return struct {
+			http.ResponseWriter
+		}{rw}
+	// combination 2/16
+	case !i0 && !i1 && !i2 && i3:
+		return struct {
+			http.ResponseWriter
+			io.ReaderFrom
+		}{rw, rw}
+	// combination 3/16
+	case !i0 && !i1 && i2 && !i3:
+		return struct {
+			http.ResponseWriter
+			http.Hijacker
+		}{rw, rw}
+	// combination 4/16
+	case !i0 && !i1 && i2 && i3:
+		return struct {
+			http.ResponseWriter
+			http.Hijacker
+			io.ReaderFrom
+		}{rw, rw, rw}
+	// combination 5/16
+	case !i0 && i1 && !i2 && !i3:
+		return struct {
+			http.ResponseWriter
+			http.CloseNotifier
+		}{rw, rw}
+	// combination 6/16
+	case !i0 && i1 && !i2 && i3:
+		return struct {
+			http.ResponseWriter
+			http.CloseNotifier
+			io.ReaderFrom
+		}{rw, rw, rw}
+	// combination 7/16
+	case !i0 && i1 && i2 && !i3:
+		return struct {
+			http.ResponseWriter
+			http.CloseNotifier
+			http.Hijacker
+		}{rw, rw, rw}
+	// combination 8/16
+	case !i0 && i1 && i2 && i3:
+		return struct {
+			http.ResponseWriter
+			http.CloseNotifier
+			http.Hijacker
+			io.ReaderFrom
+		}{rw, rw, rw, rw}
+	// combination 9/16
+	case i0 && !i1 && !i2 && !i3:
+		return struct {
+			http.ResponseWriter
+			http.Flusher
+		}{rw, rw}
+	// combination 10/16
+	case i0 && !i1 && !i2 && i3:
+		return struct {
+			http.ResponseWriter
+			http.Flusher
+			io.ReaderFrom
+		}{rw, rw, rw}
+	// combination 11/16
+	case i0 && !i1 && i2 && !i3:
+		return struct {
+			http.ResponseWriter
+			http.Flusher
+			http.Hijacker
+		}{rw, rw, rw}
+	// combination 12/16
+	case i0 && !i1 && i2 && i3:
+		return struct {
+			http.ResponseWriter
+			http.Flusher
+			http.Hijacker
+			io.ReaderFrom
+		}{rw, rw, rw, rw}
+	// combination 13/16
+	case i0 && i1 && !i2 && !i3:
+		return struct {
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+		}{rw, rw, rw}
+	// combination 14/16
+	case i0 && i1 && !i2 && i3:
+		return struct {
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			io.ReaderFrom
+		}{rw, rw, rw, rw}
+	// combination 15/16
+	case i0 && i1 && i2 && !i3:
+		return struct {
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			http.Hijacker
+		}{rw, rw, rw, rw}
+	// combination 16/16
+	case i0 && i1 && i2 && i3:
+		return struct {
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			http.Hijacker
+			io.ReaderFrom
+		}{rw, rw, rw, rw, rw}
+	}
+	panic("unreachable")
+}
+
+type rw struct {
+	w http.ResponseWriter
+	h Hooks
+}
+
+func (w *rw) Header() http.Header {
+	f := w.w.(http.ResponseWriter).Header
+	if w.h.Header != nil {
+		f = w.h.Header(f)
+	}
+	return f()
+}
+
+func (w *rw) WriteHeader(code int) {
+	f := w.w.(http.ResponseWriter).WriteHeader
+	if w.h.WriteHeader != nil {
+		f = w.h.WriteHeader(f)
+	}
+	f(code)
+}
+
+func (w *rw) Write(b []byte) (int, error) {
+	f := w.w.(http.ResponseWriter).Write
+	if w.h.Write != nil {
+		f = w.h.Write(f)
+	}
+	return f(b)
+}
+
+func (w *rw) Flush() {
+	f := w.w.(http.Flusher).Flush
+	if w.h.Flush != nil {
+		f = w.h.Flush(f)
+	}
+	f()
+}
+
+func (w *rw) CloseNotify() <-chan bool {
+	f := w.w.(http.CloseNotifier).CloseNotify
+	if w.h.CloseNotify != nil {
+		f = w.h.CloseNotify(f)
+	}
+	return f()
+}
+
+func (w *rw) Hijack() (net.Conn, *bufio.ReadWriter, error) {
+	f := w.w.(http.Hijacker).Hijack
+	if w.h.Hijack != nil {
+		f = w.h.Hijack(f)
+	}
+	return f()
+}
+
+func (w *rw) ReadFrom(src io.Reader) (int64, error) {
+	f := w.w.(io.ReaderFrom).ReadFrom
+	if w.h.ReadFrom != nil {
+		f = w.h.ReadFrom(f)
+	}
+	return f(src)
+}

vendor/github.com/gofrs/uuid/.gitignore

@@ -0,0 +1,15 @@
+# Binaries for programs and plugins
+*.exe
+*.exe~
+*.dll
+*.so
+*.dylib
+
+# Test binary, build with `go test -c`
+*.test
+
+# Output of the go coverage tool, specifically when used with LiteIDE
+*.out
+
+# binary bundle generated by go-fuzz
+uuid-fuzz.zip

vendor/github.com/gofrs/uuid/LICENSE

@@ -0,0 +1,20 @@
+Copyright (C) 2013-2018 by Maxim Bublis <b@codemonkey.ru>
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

vendor/github.com/gofrs/uuid/README.md

@@ -0,0 +1,117 @@
+# UUID
+
+[![License](https://img.shields.io/github/license/gofrs/uuid.svg)](https://github.com/gofrs/uuid/blob/master/LICENSE)
+[![Build Status](https://travis-ci.org/gofrs/uuid.svg?branch=master)](https://travis-ci.org/gofrs/uuid)
+[![GoDoc](http://godoc.org/github.com/gofrs/uuid?status.svg)](http://godoc.org/github.com/gofrs/uuid)
+[![Coverage Status](https://codecov.io/gh/gofrs/uuid/branch/master/graphs/badge.svg?branch=master)](https://codecov.io/gh/gofrs/uuid/)
+[![Go Report Card](https://goreportcard.com/badge/github.com/gofrs/uuid)](https://goreportcard.com/report/github.com/gofrs/uuid)
+
+Package uuid provides a pure Go implementation of Universally Unique Identifiers
+(UUID) variant as defined in RFC-4122. This package supports both the creation
+and parsing of UUIDs in different formats.
+
+This package supports the following UUID versions:
+* Version 1, based on timestamp and MAC address (RFC-4122)
+* Version 3, based on MD5 hashing of a named value (RFC-4122)
+* Version 4, based on random numbers (RFC-4122)
+* Version 5, based on SHA-1 hashing of a named value (RFC-4122)
+
+This package also supports experimental Universally Unique Identifier implementations based on a
+[draft RFC](https://datatracker.ietf.org/doc/html/draft-peabody-dispatch-new-uuid-format-03) that updates RFC-4122
+* Version 6, a k-sortable id based on timestamp, and field-compatible with v1 (draft-peabody-dispatch-new-uuid-format, RFC-4122)
+* Version 7, a k-sortable id based on timestamp (draft-peabody-dispatch-new-uuid-format, RFC-4122)
+
+The v6 and v7 IDs are **not** considered a part of the stable API, and may be subject to behavior or API changes as part of minor releases
+to this package. They will be updated as the draft RFC changes, and will become stable if and when the draft RFC is accepted.
+
+## Project History
+
+This project was originally forked from the
+[github.com/satori/go.uuid](https://github.com/satori/go.uuid) repository after
+it appeared to be no longer maintained, while exhibiting [critical
+flaws](https://github.com/satori/go.uuid/issues/73). We have decided to take
+over this project to ensure it receives regular maintenance for the benefit of
+the larger Go community.
+
+We'd like to thank Maxim Bublis for his hard work on the original iteration of
+the package.
+
+## License
+
+This source code of this package is released under the MIT License. Please see
+the [LICENSE](https://github.com/gofrs/uuid/blob/master/LICENSE) for the full
+content of the license.
+
+## Recommended Package Version
+
+We recommend using v2.0.0+ of this package, as versions prior to 2.0.0 were
+created before our fork of the original package and have some known
+deficiencies.
+
+## Installation
+
+It is recommended to use a package manager like `dep` that understands tagged
+releases of a package, as well as semantic versioning.
+
+If you are unable to make use of a dependency manager with your project, you can
+use the `go get` command to download it directly:
+
+```Shell
+$ go get github.com/gofrs/uuid
+```
+
+## Requirements
+
+Due to subtests not being supported in older versions of Go, this package is
+only regularly tested against Go 1.7+. This package may work perfectly fine with
+Go 1.2+, but support for these older versions is not actively maintained.
+
+## Go 1.11 Modules
+
+As of v3.2.0, this repository no longer adopts Go modules, and v3.2.0 no longer has a `go.mod` file.  As a result, v3.2.0 also drops support for the `github.com/gofrs/uuid/v3` import path. Only module-based consumers are impacted.  With the v3.2.0 release, _all_ gofrs/uuid consumers should use the `github.com/gofrs/uuid` import path.
+
+An existing module-based consumer will continue to be able to build using the `github.com/gofrs/uuid/v3` import path using any valid consumer `go.mod` that worked prior to the publishing of v3.2.0, but any module-based consumer should start using the `github.com/gofrs/uuid` import path when possible and _must_ use the `github.com/gofrs/uuid` import path prior to upgrading to v3.2.0.
+
+Please refer to [Issue #61](https://github.com/gofrs/uuid/issues/61) and [Issue #66](https://github.com/gofrs/uuid/issues/66) for more details.
+
+## Usage
+
+Here is a quick overview of how to use this package. For more detailed
+documentation, please see the [GoDoc Page](http://godoc.org/github.com/gofrs/uuid).
+
+```go
+package main
+
+import (
+	"log"
+
+	"github.com/gofrs/uuid"
+)
+
+// Create a Version 4 UUID, panicking on error.
+// Use this form to initialize package-level variables.
+var u1 = uuid.Must(uuid.NewV4())
+
+func main() {
+	// Create a Version 4 UUID.
+	u2, err := uuid.NewV4()
+	if err != nil {
+		log.Fatalf("failed to generate UUID: %v", err)
+	}
+	log.Printf("generated Version 4 UUID %v", u2)
+
+	// Parse a UUID from a string.
+	s := "6ba7b810-9dad-11d1-80b4-00c04fd430c8"
+	u3, err := uuid.FromString(s)
+	if err != nil {
+		log.Fatalf("failed to parse UUID %q: %v", s, err)
+	}
+	log.Printf("successfully parsed UUID %v", u3)
+}
+```
+
+## References
+
+* [RFC-4122](https://tools.ietf.org/html/rfc4122)
+* [DCE 1.1: Authentication and Security Services](http://pubs.opengroup.org/onlinepubs/9696989899/chap5.htm#tagcjh_08_02_01_01)
+* [New UUID Formats RFC Draft (Peabody) Rev 03](https://datatracker.ietf.org/doc/html/draft-peabody-dispatch-new-uuid-format-03)

vendor/github.com/gofrs/uuid/codec.go

@@ -0,0 +1,212 @@
+// Copyright (C) 2013-2018 by Maxim Bublis <b@codemonkey.ru>
+//
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to
+// permit persons to whom the Software is furnished to do so, subject to
+// the following conditions:
+//
+// The above copyright notice and this permission notice shall be
+// included in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+package uuid
+
+import (
+	"bytes"
+	"encoding/hex"
+	"fmt"
+)
+
+// FromBytes returns a UUID generated from the raw byte slice input.
+// It will return an error if the slice isn't 16 bytes long.
+func FromBytes(input []byte) (UUID, error) {
+	u := UUID{}
+	err := u.UnmarshalBinary(input)
+	return u, err
+}
+
+// FromBytesOrNil returns a UUID generated from the raw byte slice input.
+// Same behavior as FromBytes(), but returns uuid.Nil instead of an error.
+func FromBytesOrNil(input []byte) UUID {
+	uuid, err := FromBytes(input)
+	if err != nil {
+		return Nil
+	}
+	return uuid
+}
+
+// FromString returns a UUID parsed from the input string.
+// Input is expected in a form accepted by UnmarshalText.
+func FromString(input string) (UUID, error) {
+	u := UUID{}
+	err := u.UnmarshalText([]byte(input))
+	return u, err
+}
+
+// FromStringOrNil returns a UUID parsed from the input string.
+// Same behavior as FromString(), but returns uuid.Nil instead of an error.
+func FromStringOrNil(input string) UUID {
+	uuid, err := FromString(input)
+	if err != nil {
+		return Nil
+	}
+	return uuid
+}
+
+// MarshalText implements the encoding.TextMarshaler interface.
+// The encoding is the same as returned by the String() method.
+func (u UUID) MarshalText() ([]byte, error) {
+	return []byte(u.String()), nil
+}
+
+// UnmarshalText implements the encoding.TextUnmarshaler interface.
+// Following formats are supported:
+//
+//   "6ba7b810-9dad-11d1-80b4-00c04fd430c8",
+//   "{6ba7b810-9dad-11d1-80b4-00c04fd430c8}",
+//   "urn:uuid:6ba7b810-9dad-11d1-80b4-00c04fd430c8"
+//   "6ba7b8109dad11d180b400c04fd430c8"
+//   "{6ba7b8109dad11d180b400c04fd430c8}",
+//   "urn:uuid:6ba7b8109dad11d180b400c04fd430c8"
+//
+// ABNF for supported UUID text representation follows:
+//
+//   URN := 'urn'
+//   UUID-NID := 'uuid'
+//
+//   hexdig := '0' | '1' | '2' | '3' | '4' | '5' | '6' | '7' | '8' | '9' |
+//             'a' | 'b' | 'c' | 'd' | 'e' | 'f' |
+//             'A' | 'B' | 'C' | 'D' | 'E' | 'F'
+//
+//   hexoct := hexdig hexdig
+//   2hexoct := hexoct hexoct
+//   4hexoct := 2hexoct 2hexoct
+//   6hexoct := 4hexoct 2hexoct
+//   12hexoct := 6hexoct 6hexoct
+//
+//   hashlike := 12hexoct
+//   canonical := 4hexoct '-' 2hexoct '-' 2hexoct '-' 6hexoct
+//
+//   plain := canonical | hashlike
+//   uuid := canonical | hashlike | braced | urn
+//
+//   braced := '{' plain '}' | '{' hashlike  '}'
+//   urn := URN ':' UUID-NID ':' plain
+//
+func (u *UUID) UnmarshalText(text []byte) error {
+	switch len(text) {
+	case 32:
+		return u.decodeHashLike(text)
+	case 34, 38:
+		return u.decodeBraced(text)
+	case 36:
+		return u.decodeCanonical(text)
+	case 41, 45:
+		return u.decodeURN(text)
+	default:
+		return fmt.Errorf("uuid: incorrect UUID length %d in string %q", len(text), text)
+	}
+}
+
+// decodeCanonical decodes UUID strings that are formatted as defined in RFC-4122 (section 3):
+// "6ba7b810-9dad-11d1-80b4-00c04fd430c8".
+func (u *UUID) decodeCanonical(t []byte) error {
+	if t[8] != '-' || t[13] != '-' || t[18] != '-' || t[23] != '-' {
+		return fmt.Errorf("uuid: incorrect UUID format in string %q", t)
+	}
+
+	src := t
+	dst := u[:]
+
+	for i, byteGroup := range byteGroups {
+		if i > 0 {
+			src = src[1:] // skip dash
+		}
+		_, err := hex.Decode(dst[:byteGroup/2], src[:byteGroup])
+		if err != nil {
+			return err
+		}
+		src = src[byteGroup:]
+		dst = dst[byteGroup/2:]
+	}
+
+	return nil
+}
+
+// decodeHashLike decodes UUID strings that are using the following format:
+//  "6ba7b8109dad11d180b400c04fd430c8".
+func (u *UUID) decodeHashLike(t []byte) error {
+	src := t[:]
+	dst := u[:]
+
+	_, err := hex.Decode(dst, src)
+	return err
+}
+
+// decodeBraced decodes UUID strings that are using the following formats:
+//  "{6ba7b810-9dad-11d1-80b4-00c04fd430c8}"
+//  "{6ba7b8109dad11d180b400c04fd430c8}".
+func (u *UUID) decodeBraced(t []byte) error {
+	l := len(t)
+
+	if t[0] != '{' || t[l-1] != '}' {
+		return fmt.Errorf("uuid: incorrect UUID format in string %q", t)
+	}
+
+	return u.decodePlain(t[1 : l-1])
+}
+
+// decodeURN decodes UUID strings that are using the following formats:
+//  "urn:uuid:6ba7b810-9dad-11d1-80b4-00c04fd430c8"
+//  "urn:uuid:6ba7b8109dad11d180b400c04fd430c8".
+func (u *UUID) decodeURN(t []byte) error {
+	total := len(t)
+
+	urnUUIDPrefix := t[:9]
+
+	if !bytes.Equal(urnUUIDPrefix, urnPrefix) {
+		return fmt.Errorf("uuid: incorrect UUID format in string %q", t)
+	}
+
+	return u.decodePlain(t[9:total])
+}
+
+// decodePlain decodes UUID strings that are using the following formats:
+//  "6ba7b810-9dad-11d1-80b4-00c04fd430c8" or in hash-like format
+//  "6ba7b8109dad11d180b400c04fd430c8".
+func (u *UUID) decodePlain(t []byte) error {
+	switch len(t) {
+	case 32:
+		return u.decodeHashLike(t)
+	case 36:
+		return u.decodeCanonical(t)
+	default:
+		return fmt.Errorf("uuid: incorrect UUID length %d in string %q", len(t), t)
+	}
+}
+
+// MarshalBinary implements the encoding.BinaryMarshaler interface.
+func (u UUID) MarshalBinary() ([]byte, error) {
+	return u.Bytes(), nil
+}
+
+// UnmarshalBinary implements the encoding.BinaryUnmarshaler interface.
+// It will return an error if the slice isn't 16 bytes long.
+func (u *UUID) UnmarshalBinary(data []byte) error {
+	if len(data) != Size {
+		return fmt.Errorf("uuid: UUID must be exactly 16 bytes long, got %d bytes", len(data))
+	}
+	copy(u[:], data)
+
+	return nil
+}

vendor/github.com/gofrs/uuid/fuzz.go

@@ -0,0 +1,47 @@
+// Copyright (c) 2018 Andrei Tudor Călin <mail@acln.ro>
+//
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to
+// permit persons to whom the Software is furnished to do so, subject to
+// the following conditions:
+//
+// The above copyright notice and this permission notice shall be
+// included in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+// +build gofuzz
+
+package uuid
+
+// Fuzz implements a simple fuzz test for FromString / UnmarshalText.
+//
+// To run:
+//
+//     $ go get github.com/dvyukov/go-fuzz/...
+//     $ cd $GOPATH/src/github.com/gofrs/uuid
+//     $ go-fuzz-build github.com/gofrs/uuid
+//     $ go-fuzz -bin=uuid-fuzz.zip -workdir=./testdata
+//
+// If you make significant changes to FromString / UnmarshalText and add
+// new cases to fromStringTests (in codec_test.go), please run
+//
+//    $ go test -seed_fuzz_corpus
+//
+// to seed the corpus with the new interesting inputs, then run the fuzzer.
+func Fuzz(data []byte) int {
+	_, err := FromString(string(data))
+	if err != nil {
+		return 0
+	}
+	return 1
+}

vendor/github.com/gofrs/uuid/generator.go

@@ -0,0 +1,356 @@
+// Copyright (C) 2013-2018 by Maxim Bublis <b@codemonkey.ru>
+//
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to
+// permit persons to whom the Software is furnished to do so, subject to
+// the following conditions:
+//
+// The above copyright notice and this permission notice shall be
+// included in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+package uuid
+
+import (
+	"crypto/md5"
+	"crypto/rand"
+	"crypto/sha1"
+	"encoding/binary"
+	"fmt"
+	"hash"
+	"io"
+	"net"
+	"sync"
+	"time"
+)
+
+// Difference in 100-nanosecond intervals between
+// UUID epoch (October 15, 1582) and Unix epoch (January 1, 1970).
+const epochStart = 122192928000000000
+
+type epochFunc func() time.Time
+
+// HWAddrFunc is the function type used to provide hardware (MAC) addresses.
+type HWAddrFunc func() (net.HardwareAddr, error)
+
+// DefaultGenerator is the default UUID Generator used by this package.
+var DefaultGenerator Generator = NewGen()
+
+// NewV1 returns a UUID based on the current timestamp and MAC address.
+func NewV1() (UUID, error) {
+	return DefaultGenerator.NewV1()
+}
+
+// NewV3 returns a UUID based on the MD5 hash of the namespace UUID and name.
+func NewV3(ns UUID, name string) UUID {
+	return DefaultGenerator.NewV3(ns, name)
+}
+
+// NewV4 returns a randomly generated UUID.
+func NewV4() (UUID, error) {
+	return DefaultGenerator.NewV4()
+}
+
+// NewV5 returns a UUID based on SHA-1 hash of the namespace UUID and name.
+func NewV5(ns UUID, name string) UUID {
+	return DefaultGenerator.NewV5(ns, name)
+}
+
+// NewV6 returns a k-sortable UUID based on a timestamp and 48 bits of
+// pseudorandom data. The timestamp in a V6 UUID is the same as V1, with the bit
+// order being adjusted to allow the UUID to be k-sortable.
+//
+// This is implemented based on revision 03 of the Peabody UUID draft, and may
+// be subject to change pending further revisions. Until the final specification
+// revision is finished, changes required to implement updates to the spec will
+// not be considered a breaking change. They will happen as a minor version
+// releases until the spec is final.
+func NewV6() (UUID, error) {
+	return DefaultGenerator.NewV6()
+}
+
+// NewV7 returns a k-sortable UUID based on the current millisecond precision
+// UNIX epoch and 74 bits of pseudorandom data.
+//
+// This is implemented based on revision 03 of the Peabody UUID draft, and may
+// be subject to change pending further revisions. Until the final specification
+// revision is finished, changes required to implement updates to the spec will
+// not be considered a breaking change. They will happen as a minor version
+// releases until the spec is final.
+func NewV7() (UUID, error) {
+	return DefaultGenerator.NewV7()
+}
+
+// Generator provides an interface for generating UUIDs.
+type Generator interface {
+	NewV1() (UUID, error)
+	NewV3(ns UUID, name string) UUID
+	NewV4() (UUID, error)
+	NewV5(ns UUID, name string) UUID
+	NewV6() (UUID, error)
+	NewV7() (UUID, error)
+}
+
+// Gen is a reference UUID generator based on the specifications laid out in
+// RFC-4122 and DCE 1.1: Authentication and Security Services. This type
+// satisfies the Generator interface as defined in this package.
+//
+// For consumers who are generating V1 UUIDs, but don't want to expose the MAC
+// address of the node generating the UUIDs, the NewGenWithHWAF() function has been
+// provided as a convenience. See the function's documentation for more info.
+//
+// The authors of this package do not feel that the majority of users will need
+// to obfuscate their MAC address, and so we recommend using NewGen() to create
+// a new generator.
+type Gen struct {
+	clockSequenceOnce sync.Once
+	hardwareAddrOnce  sync.Once
+	storageMutex      sync.Mutex
+
+	rand io.Reader
+
+	epochFunc     epochFunc
+	hwAddrFunc    HWAddrFunc
+	lastTime      uint64
+	clockSequence uint16
+	hardwareAddr  [6]byte
+}
+
+// interface check -- build will fail if *Gen doesn't satisfy Generator
+var _ Generator = (*Gen)(nil)
+
+// NewGen returns a new instance of Gen with some default values set. Most
+// people should use this.
+func NewGen() *Gen {
+	return NewGenWithHWAF(defaultHWAddrFunc)
+}
+
+// NewGenWithHWAF builds a new UUID generator with the HWAddrFunc provided. Most
+// consumers should use NewGen() instead.
+//
+// This is used so that consumers can generate their own MAC addresses, for use
+// in the generated UUIDs, if there is some concern about exposing the physical
+// address of the machine generating the UUID.
+//
+// The Gen generator will only invoke the HWAddrFunc once, and cache that MAC
+// address for all the future UUIDs generated by it. If you'd like to switch the
+// MAC address being used, you'll need to create a new generator using this
+// function.
+func NewGenWithHWAF(hwaf HWAddrFunc) *Gen {
+	return &Gen{
+		epochFunc:  time.Now,
+		hwAddrFunc: hwaf,
+		rand:       rand.Reader,
+	}
+}
+
+// NewV1 returns a UUID based on the current timestamp and MAC address.
+func (g *Gen) NewV1() (UUID, error) {
+	u := UUID{}
+
+	timeNow, clockSeq, err := g.getClockSequence()
+	if err != nil {
+		return Nil, err
+	}
+	binary.BigEndian.PutUint32(u[0:], uint32(timeNow))
+	binary.BigEndian.PutUint16(u[4:], uint16(timeNow>>32))
+	binary.BigEndian.PutUint16(u[6:], uint16(timeNow>>48))
+	binary.BigEndian.PutUint16(u[8:], clockSeq)
+
+	hardwareAddr, err := g.getHardwareAddr()
+	if err != nil {
+		return Nil, err
+	}
+	copy(u[10:], hardwareAddr)
+
+	u.SetVersion(V1)
+	u.SetVariant(VariantRFC4122)
+
+	return u, nil
+}
+
+// NewV3 returns a UUID based on the MD5 hash of the namespace UUID and name.
+func (g *Gen) NewV3(ns UUID, name string) UUID {
+	u := newFromHash(md5.New(), ns, name)
+	u.SetVersion(V3)
+	u.SetVariant(VariantRFC4122)
+
+	return u
+}
+
+// NewV4 returns a randomly generated UUID.
+func (g *Gen) NewV4() (UUID, error) {
+	u := UUID{}
+	if _, err := io.ReadFull(g.rand, u[:]); err != nil {
+		return Nil, err
+	}
+	u.SetVersion(V4)
+	u.SetVariant(VariantRFC4122)
+
+	return u, nil
+}
+
+// NewV5 returns a UUID based on SHA-1 hash of the namespace UUID and name.
+func (g *Gen) NewV5(ns UUID, name string) UUID {
+	u := newFromHash(sha1.New(), ns, name)
+	u.SetVersion(V5)
+	u.SetVariant(VariantRFC4122)
+
+	return u
+}
+
+// NewV6 returns a k-sortable UUID based on a timestamp and 48 bits of
+// pseudorandom data. The timestamp in a V6 UUID is the same as V1, with the bit
+// order being adjusted to allow the UUID to be k-sortable.
+//
+// This is implemented based on revision 03 of the Peabody UUID draft, and may
+// be subject to change pending further revisions. Until the final specification
+// revision is finished, changes required to implement updates to the spec will
+// not be considered a breaking change. They will happen as a minor version
+// releases until the spec is final.
+func (g *Gen) NewV6() (UUID, error) {
+	var u UUID
+
+	if _, err := io.ReadFull(g.rand, u[10:]); err != nil {
+		return Nil, err
+	}
+
+	timeNow, clockSeq, err := g.getClockSequence()
+	if err != nil {
+		return Nil, err
+	}
+
+	binary.BigEndian.PutUint32(u[0:], uint32(timeNow>>28))   // set time_high
+	binary.BigEndian.PutUint16(u[4:], uint16(timeNow>>12))   // set time_mid
+	binary.BigEndian.PutUint16(u[6:], uint16(timeNow&0xfff)) // set time_low (minus four version bits)
+	binary.BigEndian.PutUint16(u[8:], clockSeq&0x3fff)       // set clk_seq_hi_res (minus two variant bits)
+
+	u.SetVersion(V6)
+	u.SetVariant(VariantRFC4122)
+
+	return u, nil
+}
+
+// getClockSequence returns the epoch and clock sequence for V1 and V6 UUIDs.
+func (g *Gen) getClockSequence() (uint64, uint16, error) {
+	var err error
+	g.clockSequenceOnce.Do(func() {
+		buf := make([]byte, 2)
+		if _, err = io.ReadFull(g.rand, buf); err != nil {
+			return
+		}
+		g.clockSequence = binary.BigEndian.Uint16(buf)
+	})
+	if err != nil {
+		return 0, 0, err
+	}
+
+	g.storageMutex.Lock()
+	defer g.storageMutex.Unlock()
+
+	timeNow := g.getEpoch()
+	// Clock didn't change since last UUID generation.
+	// Should increase clock sequence.
+	if timeNow <= g.lastTime {
+		g.clockSequence++
+	}
+	g.lastTime = timeNow
+
+	return timeNow, g.clockSequence, nil
+}
+
+// NewV7 returns a k-sortable UUID based on the current millisecond precision
+// UNIX epoch and 74 bits of pseudorandom data.
+//
+// This is implemented based on revision 03 of the Peabody UUID draft, and may
+// be subject to change pending further revisions. Until the final specification
+// revision is finished, changes required to implement updates to the spec will
+// not be considered a breaking change. They will happen as a minor version
+// releases until the spec is final.
+func (g *Gen) NewV7() (UUID, error) {
+	var u UUID
+
+	if _, err := io.ReadFull(g.rand, u[6:]); err != nil {
+		return Nil, err
+	}
+
+	tn := g.epochFunc()
+	ms := uint64(tn.Unix())*1e3 + uint64(tn.Nanosecond())/1e6
+	u[0] = byte(ms >> 40)
+	u[1] = byte(ms >> 32)
+	u[2] = byte(ms >> 24)
+	u[3] = byte(ms >> 16)
+	u[4] = byte(ms >> 8)
+	u[5] = byte(ms)
+
+	u.SetVersion(V7)
+	u.SetVariant(VariantRFC4122)
+
+	return u, nil
+}
+
+// Returns the hardware address.
+func (g *Gen) getHardwareAddr() ([]byte, error) {
+	var err error
+	g.hardwareAddrOnce.Do(func() {
+		var hwAddr net.HardwareAddr
+		if hwAddr, err = g.hwAddrFunc(); err == nil {
+			copy(g.hardwareAddr[:], hwAddr)
+			return
+		}
+
+		// Initialize hardwareAddr randomly in case
+		// of real network interfaces absence.
+		if _, err = io.ReadFull(g.rand, g.hardwareAddr[:]); err != nil {
+			return
+		}
+		// Set multicast bit as recommended by RFC-4122
+		g.hardwareAddr[0] |= 0x01
+	})
+	if err != nil {
+		return []byte{}, err
+	}
+	return g.hardwareAddr[:], nil
+}
+
+// Returns the difference between UUID epoch (October 15, 1582)
+// and current time in 100-nanosecond intervals.
+func (g *Gen) getEpoch() uint64 {
+	return epochStart + uint64(g.epochFunc().UnixNano()/100)
+}
+
+// Returns the UUID based on the hashing of the namespace UUID and name.
+func newFromHash(h hash.Hash, ns UUID, name string) UUID {
+	u := UUID{}
+	h.Write(ns[:])
+	h.Write([]byte(name))
+	copy(u[:], h.Sum(nil))
+
+	return u
+}
+
+var netInterfaces = net.Interfaces
+
+// Returns the hardware address.
+func defaultHWAddrFunc() (net.HardwareAddr, error) {
+	ifaces, err := netInterfaces()
+	if err != nil {
+		return []byte{}, err
+	}
+	for _, iface := range ifaces {
+		if len(iface.HardwareAddr) >= 6 {
+			return iface.HardwareAddr, nil
+		}
+	}
+	return []byte{}, fmt.Errorf("uuid: no HW address found")
+}

vendor/github.com/gofrs/uuid/sql.go

@@ -0,0 +1,109 @@
+// Copyright (C) 2013-2018 by Maxim Bublis <b@codemonkey.ru>
+//
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to
+// permit persons to whom the Software is furnished to do so, subject to
+// the following conditions:
+//
+// The above copyright notice and this permission notice shall be
+// included in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+package uuid
+
+import (
+	"bytes"
+	"database/sql/driver"
+	"encoding/json"
+	"fmt"
+)
+
+// Value implements the driver.Valuer interface.
+func (u UUID) Value() (driver.Value, error) {
+	return u.String(), nil
+}
+
+// Scan implements the sql.Scanner interface.
+// A 16-byte slice will be handled by UnmarshalBinary, while
+// a longer byte slice or a string will be handled by UnmarshalText.
+func (u *UUID) Scan(src interface{}) error {
+	switch src := src.(type) {
+	case UUID: // support gorm convert from UUID to NullUUID
+		*u = src
+		return nil
+
+	case []byte:
+		if len(src) == Size {
+			return u.UnmarshalBinary(src)
+		}
+		return u.UnmarshalText(src)
+
+	case string:
+		return u.UnmarshalText([]byte(src))
+	}
+
+	return fmt.Errorf("uuid: cannot convert %T to UUID", src)
+}
+
+// NullUUID can be used with the standard sql package to represent a
+// UUID value that can be NULL in the database.
+type NullUUID struct {
+	UUID  UUID
+	Valid bool
+}
+
+// Value implements the driver.Valuer interface.
+func (u NullUUID) Value() (driver.Value, error) {
+	if !u.Valid {
+		return nil, nil
+	}
+	// Delegate to UUID Value function
+	return u.UUID.Value()
+}
+
+// Scan implements the sql.Scanner interface.
+func (u *NullUUID) Scan(src interface{}) error {
+	if src == nil {
+		u.UUID, u.Valid = Nil, false
+		return nil
+	}
+
+	// Delegate to UUID Scan function
+	u.Valid = true
+	return u.UUID.Scan(src)
+}
+
+// MarshalJSON marshals the NullUUID as null or the nested UUID
+func (u NullUUID) MarshalJSON() ([]byte, error) {
+	if !u.Valid {
+		return json.Marshal(nil)
+	}
+
+	return json.Marshal(u.UUID)
+}
+
+// UnmarshalJSON unmarshals a NullUUID
+func (u *NullUUID) UnmarshalJSON(b []byte) error {
+	if bytes.Equal(b, []byte("null")) {
+		u.UUID, u.Valid = Nil, false
+		return nil
+	}
+
+	if err := json.Unmarshal(b, &u.UUID); err != nil {
+		return err
+	}
+
+	u.Valid = true
+
+	return nil
+}

vendor/github.com/gofrs/uuid/uuid.go

@@ -0,0 +1,292 @@
+// Copyright (C) 2013-2018 by Maxim Bublis <b@codemonkey.ru>
+//
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to
+// permit persons to whom the Software is furnished to do so, subject to
+// the following conditions:
+//
+// The above copyright notice and this permission notice shall be
+// included in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+// Package uuid provides implementations of the Universally Unique Identifier
+// (UUID), as specified in RFC-4122 and the Peabody RFC Draft (revision 03).
+//
+// RFC-4122[1] provides the specification for versions 1, 3, 4, and 5. The
+// Peabody UUID RFC Draft[2] provides the specification for the new k-sortable
+// UUIDs, versions 6 and 7.
+//
+// DCE 1.1[3] provides the specification for version 2, but version 2 support
+// was removed from this package in v4 due to some concerns with the
+// specification itself. Reading the spec, it seems that it would result in
+// generating UUIDs that aren't very unique. In having read the spec it seemed
+// that our implementation did not meet the spec. It also seems to be at-odds
+// with RFC 4122, meaning we would need quite a bit of special code to support
+// it. Lastly, there were no Version 2 implementations that we could find to
+// ensure we were understanding the specification correctly.
+//
+// [1] https://tools.ietf.org/html/rfc4122
+// [2] https://datatracker.ietf.org/doc/html/draft-peabody-dispatch-new-uuid-format-03
+// [3] http://pubs.opengroup.org/onlinepubs/9696989899/chap5.htm#tagcjh_08_02_01_01
+package uuid
+
+import (
+	"encoding/binary"
+	"encoding/hex"
+	"fmt"
+	"io"
+	"strings"
+	"time"
+)
+
+// Size of a UUID in bytes.
+const Size = 16
+
+// UUID is an array type to represent the value of a UUID, as defined in RFC-4122.
+type UUID [Size]byte
+
+// UUID versions.
+const (
+	_  byte = iota
+	V1      // Version 1 (date-time and MAC address)
+	_       // Version 2 (date-time and MAC address, DCE security version) [removed]
+	V3      // Version 3 (namespace name-based)
+	V4      // Version 4 (random)
+	V5      // Version 5 (namespace name-based)
+	V6      // Version 6 (k-sortable timestamp and random data, field-compatible with v1) [peabody draft]
+	V7      // Version 7 (k-sortable timestamp and random data) [peabody draft]
+	_       // Version 8 (k-sortable timestamp, meant for custom implementations) [peabody draft] [not implemented]
+)
+
+// UUID layout variants.
+const (
+	VariantNCS byte = iota
+	VariantRFC4122
+	VariantMicrosoft
+	VariantFuture
+)
+
+// UUID DCE domains.
+const (
+	DomainPerson = iota
+	DomainGroup
+	DomainOrg
+)
+
+// Timestamp is the count of 100-nanosecond intervals since 00:00:00.00,
+// 15 October 1582 within a V1 UUID. This type has no meaning for other
+// UUID versions since they don't have an embedded timestamp.
+type Timestamp uint64
+
+const _100nsPerSecond = 10000000
+
+// Time returns the UTC time.Time representation of a Timestamp
+func (t Timestamp) Time() (time.Time, error) {
+	secs := uint64(t) / _100nsPerSecond
+	nsecs := 100 * (uint64(t) % _100nsPerSecond)
+
+	return time.Unix(int64(secs)-(epochStart/_100nsPerSecond), int64(nsecs)), nil
+}
+
+// TimestampFromV1 returns the Timestamp embedded within a V1 UUID.
+// Returns an error if the UUID is any version other than 1.
+func TimestampFromV1(u UUID) (Timestamp, error) {
+	if u.Version() != 1 {
+		err := fmt.Errorf("uuid: %s is version %d, not version 1", u, u.Version())
+		return 0, err
+	}
+
+	low := binary.BigEndian.Uint32(u[0:4])
+	mid := binary.BigEndian.Uint16(u[4:6])
+	hi := binary.BigEndian.Uint16(u[6:8]) & 0xfff
+
+	return Timestamp(uint64(low) + (uint64(mid) << 32) + (uint64(hi) << 48)), nil
+}
+
+// TimestampFromV6 returns the Timestamp embedded within a V6 UUID. This
+// function returns an error if the UUID is any version other than 6.
+//
+// This is implemented based on revision 03 of the Peabody UUID draft, and may
+// be subject to change pending further revisions. Until the final specification
+// revision is finished, changes required to implement updates to the spec will
+// not be considered a breaking change. They will happen as a minor version
+// releases until the spec is final.
+func TimestampFromV6(u UUID) (Timestamp, error) {
+	if u.Version() != 6 {
+		return 0, fmt.Errorf("uuid: %s is version %d, not version 6", u, u.Version())
+	}
+
+	hi := binary.BigEndian.Uint32(u[0:4])
+	mid := binary.BigEndian.Uint16(u[4:6])
+	low := binary.BigEndian.Uint16(u[6:8]) & 0xfff
+
+	return Timestamp(uint64(low) + (uint64(mid) << 12) + (uint64(hi) << 28)), nil
+}
+
+// String parse helpers.
+var (
+	urnPrefix  = []byte("urn:uuid:")
+	byteGroups = []int{8, 4, 4, 4, 12}
+)
+
+// Nil is the nil UUID, as specified in RFC-4122, that has all 128 bits set to
+// zero.
+var Nil = UUID{}
+
+// Predefined namespace UUIDs.
+var (
+	NamespaceDNS  = Must(FromString("6ba7b810-9dad-11d1-80b4-00c04fd430c8"))
+	NamespaceURL  = Must(FromString("6ba7b811-9dad-11d1-80b4-00c04fd430c8"))
+	NamespaceOID  = Must(FromString("6ba7b812-9dad-11d1-80b4-00c04fd430c8"))
+	NamespaceX500 = Must(FromString("6ba7b814-9dad-11d1-80b4-00c04fd430c8"))
+)
+
+// IsNil returns if the UUID is equal to the nil UUID
+func (u UUID) IsNil() bool {
+	return u == Nil
+}
+
+// Version returns the algorithm version used to generate the UUID.
+func (u UUID) Version() byte {
+	return u[6] >> 4
+}
+
+// Variant returns the UUID layout variant.
+func (u UUID) Variant() byte {
+	switch {
+	case (u[8] >> 7) == 0x00:
+		return VariantNCS
+	case (u[8] >> 6) == 0x02:
+		return VariantRFC4122
+	case (u[8] >> 5) == 0x06:
+		return VariantMicrosoft
+	case (u[8] >> 5) == 0x07:
+		fallthrough
+	default:
+		return VariantFuture
+	}
+}
+
+// Bytes returns a byte slice representation of the UUID.
+func (u UUID) Bytes() []byte {
+	return u[:]
+}
+
+// String returns a canonical RFC-4122 string representation of the UUID:
+// xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx.
+func (u UUID) String() string {
+	buf := make([]byte, 36)
+
+	hex.Encode(buf[0:8], u[0:4])
+	buf[8] = '-'
+	hex.Encode(buf[9:13], u[4:6])
+	buf[13] = '-'
+	hex.Encode(buf[14:18], u[6:8])
+	buf[18] = '-'
+	hex.Encode(buf[19:23], u[8:10])
+	buf[23] = '-'
+	hex.Encode(buf[24:], u[10:])
+
+	return string(buf)
+}
+
+// Format implements fmt.Formatter for UUID values.
+//
+// The behavior is as follows:
+// The 'x' and 'X' verbs output only the hex digits of the UUID, using a-f for 'x' and A-F for 'X'.
+// The 'v', '+v', 's' and 'q' verbs return the canonical RFC-4122 string representation.
+// The 'S' verb returns the RFC-4122 format, but with capital hex digits.
+// The '#v' verb returns the "Go syntax" representation, which is a 16 byte array initializer.
+// All other verbs not handled directly by the fmt package (like '%p') are unsupported and will return
+// "%!verb(uuid.UUID=value)" as recommended by the fmt package.
+func (u UUID) Format(f fmt.State, c rune) {
+	switch c {
+	case 'x', 'X':
+		s := hex.EncodeToString(u.Bytes())
+		if c == 'X' {
+			s = strings.Map(toCapitalHexDigits, s)
+		}
+		_, _ = io.WriteString(f, s)
+	case 'v':
+		var s string
+		if f.Flag('#') {
+			s = fmt.Sprintf("%#v", [Size]byte(u))
+		} else {
+			s = u.String()
+		}
+		_, _ = io.WriteString(f, s)
+	case 's', 'S':
+		s := u.String()
+		if c == 'S' {
+			s = strings.Map(toCapitalHexDigits, s)
+		}
+		_, _ = io.WriteString(f, s)
+	case 'q':
+		_, _ = io.WriteString(f, `"`+u.String()+`"`)
+	default:
+		// invalid/unsupported format verb
+		fmt.Fprintf(f, "%%!%c(uuid.UUID=%s)", c, u.String())
+	}
+}
+
+func toCapitalHexDigits(ch rune) rune {
+	// convert a-f hex digits to A-F
+	switch ch {
+	case 'a':
+		return 'A'
+	case 'b':
+		return 'B'
+	case 'c':
+		return 'C'
+	case 'd':
+		return 'D'
+	case 'e':
+		return 'E'
+	case 'f':
+		return 'F'
+	default:
+		return ch
+	}
+}
+
+// SetVersion sets the version bits.
+func (u *UUID) SetVersion(v byte) {
+	u[6] = (u[6] & 0x0f) | (v << 4)
+}
+
+// SetVariant sets the variant bits.
+func (u *UUID) SetVariant(v byte) {
+	switch v {
+	case VariantNCS:
+		u[8] = (u[8]&(0xff>>1) | (0x00 << 7))
+	case VariantRFC4122:
+		u[8] = (u[8]&(0xff>>2) | (0x02 << 6))
+	case VariantMicrosoft:
+		u[8] = (u[8]&(0xff>>3) | (0x06 << 5))
+	case VariantFuture:
+		fallthrough
+	default:
+		u[8] = (u[8]&(0xff>>3) | (0x07 << 5))
+	}
+}
+
+// Must is a helper that wraps a call to a function returning (UUID, error)
+// and panics if the error is non-nil. It is intended for use in variable
+// initializations such as
+//  var packageUUID = uuid.Must(uuid.FromString("123e4567-e89b-12d3-a456-426655440000"))
+func Must(u UUID, err error) UUID {
+	if err != nil {
+		panic(err)
+	}
+	return u
+}

vendor/github.com/gorilla/handlers/LICENSE

@@ -0,0 +1,22 @@
+Copyright (c) 2013 The Gorilla Handlers Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+  Redistributions of source code must retain the above copyright notice, this
+  list of conditions and the following disclaimer.
+
+  Redistributions in binary form must reproduce the above copyright notice,
+  this list of conditions and the following disclaimer in the documentation
+  and/or other materials provided with the distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/github.com/gorilla/handlers/README.md

@@ -0,0 +1,56 @@
+gorilla/handlers
+================
+[![GoDoc](https://godoc.org/github.com/gorilla/handlers?status.svg)](https://godoc.org/github.com/gorilla/handlers)
+[![CircleCI](https://circleci.com/gh/gorilla/handlers.svg?style=svg)](https://circleci.com/gh/gorilla/handlers)
+[![Sourcegraph](https://sourcegraph.com/github.com/gorilla/handlers/-/badge.svg)](https://sourcegraph.com/github.com/gorilla/handlers?badge)
+
+
+Package handlers is a collection of handlers (aka "HTTP middleware") for use
+with Go's `net/http` package (or any framework supporting `http.Handler`), including:
+
+* [**LoggingHandler**](https://godoc.org/github.com/gorilla/handlers#LoggingHandler) for logging HTTP requests in the Apache [Common Log
+  Format](http://httpd.apache.org/docs/2.2/logs.html#common).
+* [**CombinedLoggingHandler**](https://godoc.org/github.com/gorilla/handlers#CombinedLoggingHandler) for logging HTTP requests in the Apache [Combined Log
+  Format](http://httpd.apache.org/docs/2.2/logs.html#combined) commonly used by
+  both Apache and nginx.
+* [**CompressHandler**](https://godoc.org/github.com/gorilla/handlers#CompressHandler) for gzipping responses.
+* [**ContentTypeHandler**](https://godoc.org/github.com/gorilla/handlers#ContentTypeHandler) for validating requests against a list of accepted
+  content types.
+* [**MethodHandler**](https://godoc.org/github.com/gorilla/handlers#MethodHandler) for matching HTTP methods against handlers in a
+  `map[string]http.Handler`
+* [**ProxyHeaders**](https://godoc.org/github.com/gorilla/handlers#ProxyHeaders) for populating `r.RemoteAddr` and `r.URL.Scheme` based on the
+  `X-Forwarded-For`, `X-Real-IP`, `X-Forwarded-Proto` and RFC7239 `Forwarded`
+  headers when running a Go server behind a HTTP reverse proxy.
+* [**CanonicalHost**](https://godoc.org/github.com/gorilla/handlers#CanonicalHost) for re-directing to the preferred host when handling multiple 
+  domains (i.e. multiple CNAME aliases).
+* [**RecoveryHandler**](https://godoc.org/github.com/gorilla/handlers#RecoveryHandler) for recovering from unexpected panics.
+
+Other handlers are documented [on the Gorilla
+website](https://www.gorillatoolkit.org/pkg/handlers).
+
+## Example
+
+A simple example using `handlers.LoggingHandler` and `handlers.CompressHandler`:
+
+```go
+import (
+    "net/http"
+    "github.com/gorilla/handlers"
+)
+
+func main() {
+    r := http.NewServeMux()
+
+    // Only log requests to our admin dashboard to stdout
+    r.Handle("/admin", handlers.LoggingHandler(os.Stdout, http.HandlerFunc(ShowAdminDashboard)))
+    r.HandleFunc("/", ShowIndex)
+
+    // Wrap our server with our gzip handler to gzip compress all responses.
+    http.ListenAndServe(":8000", handlers.CompressHandler(r))
+}
+```
+
+## License
+
+BSD licensed. See the included LICENSE file for details.
+

vendor/github.com/gorilla/handlers/canonical.go

@@ -0,0 +1,74 @@
+package handlers
+
+import (
+	"net/http"
+	"net/url"
+	"strings"
+)
+
+type canonical struct {
+	h      http.Handler
+	domain string
+	code   int
+}
+
+// CanonicalHost is HTTP middleware that re-directs requests to the canonical
+// domain. It accepts a domain and a status code (e.g. 301 or 302) and
+// re-directs clients to this domain. The existing request path is maintained.
+//
+// Note: If the provided domain is considered invalid by url.Parse or otherwise
+// returns an empty scheme or host, clients are not re-directed.
+//
+// Example:
+//
+//  r := mux.NewRouter()
+//  canonical := handlers.CanonicalHost("http://www.gorillatoolkit.org", 302)
+//  r.HandleFunc("/route", YourHandler)
+//
+//  log.Fatal(http.ListenAndServe(":7000", canonical(r)))
+//
+func CanonicalHost(domain string, code int) func(h http.Handler) http.Handler {
+	fn := func(h http.Handler) http.Handler {
+		return canonical{h, domain, code}
+	}
+
+	return fn
+}
+
+func (c canonical) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	dest, err := url.Parse(c.domain)
+	if err != nil {
+		// Call the next handler if the provided domain fails to parse.
+		c.h.ServeHTTP(w, r)
+		return
+	}
+
+	if dest.Scheme == "" || dest.Host == "" {
+		// Call the next handler if the scheme or host are empty.
+		// Note that url.Parse won't fail on in this case.
+		c.h.ServeHTTP(w, r)
+		return
+	}
+
+	if !strings.EqualFold(cleanHost(r.Host), dest.Host) {
+		// Re-build the destination URL
+		dest := dest.Scheme + "://" + dest.Host + r.URL.Path
+		if r.URL.RawQuery != "" {
+			dest += "?" + r.URL.RawQuery
+		}
+		http.Redirect(w, r, dest, c.code)
+		return
+	}
+
+	c.h.ServeHTTP(w, r)
+}
+
+// cleanHost cleans invalid Host headers by stripping anything after '/' or ' '.
+// This is backported from Go 1.5 (in response to issue #11206) and attempts to
+// mitigate malformed Host headers that do not match the format in RFC7230.
+func cleanHost(in string) string {
+	if i := strings.IndexAny(in, " /"); i != -1 {
+		return in[:i]
+	}
+	return in
+}

vendor/github.com/gorilla/handlers/compress.go

@@ -0,0 +1,143 @@
+// Copyright 2013 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package handlers
+
+import (
+	"compress/flate"
+	"compress/gzip"
+	"io"
+	"net/http"
+	"strings"
+
+	"github.com/felixge/httpsnoop"
+)
+
+const acceptEncoding string = "Accept-Encoding"
+
+type compressResponseWriter struct {
+	compressor io.Writer
+	w          http.ResponseWriter
+}
+
+func (cw *compressResponseWriter) WriteHeader(c int) {
+	cw.w.Header().Del("Content-Length")
+	cw.w.WriteHeader(c)
+}
+
+func (cw *compressResponseWriter) Write(b []byte) (int, error) {
+	h := cw.w.Header()
+	if h.Get("Content-Type") == "" {
+		h.Set("Content-Type", http.DetectContentType(b))
+	}
+	h.Del("Content-Length")
+
+	return cw.compressor.Write(b)
+}
+
+func (cw *compressResponseWriter) ReadFrom(r io.Reader) (int64, error) {
+	return io.Copy(cw.compressor, r)
+}
+
+type flusher interface {
+	Flush() error
+}
+
+func (w *compressResponseWriter) Flush() {
+	// Flush compressed data if compressor supports it.
+	if f, ok := w.compressor.(flusher); ok {
+		f.Flush()
+	}
+	// Flush HTTP response.
+	if f, ok := w.w.(http.Flusher); ok {
+		f.Flush()
+	}
+}
+
+// CompressHandler gzip compresses HTTP responses for clients that support it
+// via the 'Accept-Encoding' header.
+//
+// Compressing TLS traffic may leak the page contents to an attacker if the
+// page contains user input: http://security.stackexchange.com/a/102015/12208
+func CompressHandler(h http.Handler) http.Handler {
+	return CompressHandlerLevel(h, gzip.DefaultCompression)
+}
+
+// CompressHandlerLevel gzip compresses HTTP responses with specified compression level
+// for clients that support it via the 'Accept-Encoding' header.
+//
+// The compression level should be gzip.DefaultCompression, gzip.NoCompression,
+// or any integer value between gzip.BestSpeed and gzip.BestCompression inclusive.
+// gzip.DefaultCompression is used in case of invalid compression level.
+func CompressHandlerLevel(h http.Handler, level int) http.Handler {
+	if level < gzip.DefaultCompression || level > gzip.BestCompression {
+		level = gzip.DefaultCompression
+	}
+
+	const (
+		gzipEncoding  = "gzip"
+		flateEncoding = "deflate"
+	)
+
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		// detect what encoding to use
+		var encoding string
+		for _, curEnc := range strings.Split(r.Header.Get(acceptEncoding), ",") {
+			curEnc = strings.TrimSpace(curEnc)
+			if curEnc == gzipEncoding || curEnc == flateEncoding {
+				encoding = curEnc
+				break
+			}
+		}
+
+		// always add Accept-Encoding to Vary to prevent intermediate caches corruption
+		w.Header().Add("Vary", acceptEncoding)
+
+		// if we weren't able to identify an encoding we're familiar with, pass on the
+		// request to the handler and return
+		if encoding == "" {
+			h.ServeHTTP(w, r)
+			return
+		}
+
+		if r.Header.Get("Upgrade") != "" {
+			h.ServeHTTP(w, r)
+			return
+		}
+
+		// wrap the ResponseWriter with the writer for the chosen encoding
+		var encWriter io.WriteCloser
+		if encoding == gzipEncoding {
+			encWriter, _ = gzip.NewWriterLevel(w, level)
+		} else if encoding == flateEncoding {
+			encWriter, _ = flate.NewWriter(w, level)
+		}
+		defer encWriter.Close()
+
+		w.Header().Set("Content-Encoding", encoding)
+		r.Header.Del(acceptEncoding)
+
+		cw := &compressResponseWriter{
+			w:          w,
+			compressor: encWriter,
+		}
+
+		w = httpsnoop.Wrap(w, httpsnoop.Hooks{
+			Write: func(httpsnoop.WriteFunc) httpsnoop.WriteFunc {
+				return cw.Write
+			},
+			WriteHeader: func(httpsnoop.WriteHeaderFunc) httpsnoop.WriteHeaderFunc {
+				return cw.WriteHeader
+			},
+			Flush: func(httpsnoop.FlushFunc) httpsnoop.FlushFunc {
+				return cw.Flush
+			},
+			ReadFrom: func(rff httpsnoop.ReadFromFunc) httpsnoop.ReadFromFunc {
+				return cw.ReadFrom
+			},
+		})
+
+		h.ServeHTTP(w, r)
+	})
+}

vendor/github.com/gorilla/handlers/cors.go

@@ -0,0 +1,355 @@
+package handlers
+
+import (
+	"net/http"
+	"strconv"
+	"strings"
+)
+
+// CORSOption represents a functional option for configuring the CORS middleware.
+type CORSOption func(*cors) error
+
+type cors struct {
+	h                      http.Handler
+	allowedHeaders         []string
+	allowedMethods         []string
+	allowedOrigins         []string
+	allowedOriginValidator OriginValidator
+	exposedHeaders         []string
+	maxAge                 int
+	ignoreOptions          bool
+	allowCredentials       bool
+	optionStatusCode       int
+}
+
+// OriginValidator takes an origin string and returns whether or not that origin is allowed.
+type OriginValidator func(string) bool
+
+var (
+	defaultCorsOptionStatusCode = 200
+	defaultCorsMethods          = []string{"GET", "HEAD", "POST"}
+	defaultCorsHeaders          = []string{"Accept", "Accept-Language", "Content-Language", "Origin"}
+	// (WebKit/Safari v9 sends the Origin header by default in AJAX requests)
+)
+
+const (
+	corsOptionMethod           string = "OPTIONS"
+	corsAllowOriginHeader      string = "Access-Control-Allow-Origin"
+	corsExposeHeadersHeader    string = "Access-Control-Expose-Headers"
+	corsMaxAgeHeader           string = "Access-Control-Max-Age"
+	corsAllowMethodsHeader     string = "Access-Control-Allow-Methods"
+	corsAllowHeadersHeader     string = "Access-Control-Allow-Headers"
+	corsAllowCredentialsHeader string = "Access-Control-Allow-Credentials"
+	corsRequestMethodHeader    string = "Access-Control-Request-Method"
+	corsRequestHeadersHeader   string = "Access-Control-Request-Headers"
+	corsOriginHeader           string = "Origin"
+	corsVaryHeader             string = "Vary"
+	corsOriginMatchAll         string = "*"
+)
+
+func (ch *cors) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	origin := r.Header.Get(corsOriginHeader)
+	if !ch.isOriginAllowed(origin) {
+		if r.Method != corsOptionMethod || ch.ignoreOptions {
+			ch.h.ServeHTTP(w, r)
+		}
+
+		return
+	}
+
+	if r.Method == corsOptionMethod {
+		if ch.ignoreOptions {
+			ch.h.ServeHTTP(w, r)
+			return
+		}
+
+		if _, ok := r.Header[corsRequestMethodHeader]; !ok {
+			w.WriteHeader(http.StatusBadRequest)
+			return
+		}
+
+		method := r.Header.Get(corsRequestMethodHeader)
+		if !ch.isMatch(method, ch.allowedMethods) {
+			w.WriteHeader(http.StatusMethodNotAllowed)
+			return
+		}
+
+		requestHeaders := strings.Split(r.Header.Get(corsRequestHeadersHeader), ",")
+		allowedHeaders := []string{}
+		for _, v := range requestHeaders {
+			canonicalHeader := http.CanonicalHeaderKey(strings.TrimSpace(v))
+			if canonicalHeader == "" || ch.isMatch(canonicalHeader, defaultCorsHeaders) {
+				continue
+			}
+
+			if !ch.isMatch(canonicalHeader, ch.allowedHeaders) {
+				w.WriteHeader(http.StatusForbidden)
+				return
+			}
+
+			allowedHeaders = append(allowedHeaders, canonicalHeader)
+		}
+
+		if len(allowedHeaders) > 0 {
+			w.Header().Set(corsAllowHeadersHeader, strings.Join(allowedHeaders, ","))
+		}
+
+		if ch.maxAge > 0 {
+			w.Header().Set(corsMaxAgeHeader, strconv.Itoa(ch.maxAge))
+		}
+
+		if !ch.isMatch(method, defaultCorsMethods) {
+			w.Header().Set(corsAllowMethodsHeader, method)
+		}
+	} else {
+		if len(ch.exposedHeaders) > 0 {
+			w.Header().Set(corsExposeHeadersHeader, strings.Join(ch.exposedHeaders, ","))
+		}
+	}
+
+	if ch.allowCredentials {
+		w.Header().Set(corsAllowCredentialsHeader, "true")
+	}
+
+	if len(ch.allowedOrigins) > 1 {
+		w.Header().Set(corsVaryHeader, corsOriginHeader)
+	}
+
+	returnOrigin := origin
+	if ch.allowedOriginValidator == nil && len(ch.allowedOrigins) == 0 {
+		returnOrigin = "*"
+	} else {
+		for _, o := range ch.allowedOrigins {
+			// A configuration of * is different than explicitly setting an allowed
+			// origin. Returning arbitrary origin headers in an access control allow
+			// origin header is unsafe and is not required by any use case.
+			if o == corsOriginMatchAll {
+				returnOrigin = "*"
+				break
+			}
+		}
+	}
+	w.Header().Set(corsAllowOriginHeader, returnOrigin)
+
+	if r.Method == corsOptionMethod {
+		w.WriteHeader(ch.optionStatusCode)
+		return
+	}
+	ch.h.ServeHTTP(w, r)
+}
+
+// CORS provides Cross-Origin Resource Sharing middleware.
+// Example:
+//
+//  import (
+//      "net/http"
+//
+//      "github.com/gorilla/handlers"
+//      "github.com/gorilla/mux"
+//  )
+//
+//  func main() {
+//      r := mux.NewRouter()
+//      r.HandleFunc("/users", UserEndpoint)
+//      r.HandleFunc("/projects", ProjectEndpoint)
+//
+//      // Apply the CORS middleware to our top-level router, with the defaults.
+//      http.ListenAndServe(":8000", handlers.CORS()(r))
+//  }
+//
+func CORS(opts ...CORSOption) func(http.Handler) http.Handler {
+	return func(h http.Handler) http.Handler {
+		ch := parseCORSOptions(opts...)
+		ch.h = h
+		return ch
+	}
+}
+
+func parseCORSOptions(opts ...CORSOption) *cors {
+	ch := &cors{
+		allowedMethods:   defaultCorsMethods,
+		allowedHeaders:   defaultCorsHeaders,
+		allowedOrigins:   []string{},
+		optionStatusCode: defaultCorsOptionStatusCode,
+	}
+
+	for _, option := range opts {
+		option(ch)
+	}
+
+	return ch
+}
+
+//
+// Functional options for configuring CORS.
+//
+
+// AllowedHeaders adds the provided headers to the list of allowed headers in a
+// CORS request.
+// This is an append operation so the headers Accept, Accept-Language,
+// and Content-Language are always allowed.
+// Content-Type must be explicitly declared if accepting Content-Types other than
+// application/x-www-form-urlencoded, multipart/form-data, or text/plain.
+func AllowedHeaders(headers []string) CORSOption {
+	return func(ch *cors) error {
+		for _, v := range headers {
+			normalizedHeader := http.CanonicalHeaderKey(strings.TrimSpace(v))
+			if normalizedHeader == "" {
+				continue
+			}
+
+			if !ch.isMatch(normalizedHeader, ch.allowedHeaders) {
+				ch.allowedHeaders = append(ch.allowedHeaders, normalizedHeader)
+			}
+		}
+
+		return nil
+	}
+}
+
+// AllowedMethods can be used to explicitly allow methods in the
+// Access-Control-Allow-Methods header.
+// This is a replacement operation so you must also
+// pass GET, HEAD, and POST if you wish to support those methods.
+func AllowedMethods(methods []string) CORSOption {
+	return func(ch *cors) error {
+		ch.allowedMethods = []string{}
+		for _, v := range methods {
+			normalizedMethod := strings.ToUpper(strings.TrimSpace(v))
+			if normalizedMethod == "" {
+				continue
+			}
+
+			if !ch.isMatch(normalizedMethod, ch.allowedMethods) {
+				ch.allowedMethods = append(ch.allowedMethods, normalizedMethod)
+			}
+		}
+
+		return nil
+	}
+}
+
+// AllowedOrigins sets the allowed origins for CORS requests, as used in the
+// 'Allow-Access-Control-Origin' HTTP header.
+// Note: Passing in a []string{"*"} will allow any domain.
+func AllowedOrigins(origins []string) CORSOption {
+	return func(ch *cors) error {
+		for _, v := range origins {
+			if v == corsOriginMatchAll {
+				ch.allowedOrigins = []string{corsOriginMatchAll}
+				return nil
+			}
+		}
+
+		ch.allowedOrigins = origins
+		return nil
+	}
+}
+
+// AllowedOriginValidator sets a function for evaluating allowed origins in CORS requests, represented by the
+// 'Allow-Access-Control-Origin' HTTP header.
+func AllowedOriginValidator(fn OriginValidator) CORSOption {
+	return func(ch *cors) error {
+		ch.allowedOriginValidator = fn
+		return nil
+	}
+}
+
+// OptionStatusCode sets a custom status code on the OPTIONS requests.
+// Default behaviour sets it to 200 to reflect best practices. This is option is not mandatory
+// and can be used if you need a custom status code (i.e 204).
+//
+// More informations on the spec:
+// https://fetch.spec.whatwg.org/#cors-preflight-fetch
+func OptionStatusCode(code int) CORSOption {
+	return func(ch *cors) error {
+		ch.optionStatusCode = code
+		return nil
+	}
+}
+
+// ExposedHeaders can be used to specify headers that are available
+// and will not be stripped out by the user-agent.
+func ExposedHeaders(headers []string) CORSOption {
+	return func(ch *cors) error {
+		ch.exposedHeaders = []string{}
+		for _, v := range headers {
+			normalizedHeader := http.CanonicalHeaderKey(strings.TrimSpace(v))
+			if normalizedHeader == "" {
+				continue
+			}
+
+			if !ch.isMatch(normalizedHeader, ch.exposedHeaders) {
+				ch.exposedHeaders = append(ch.exposedHeaders, normalizedHeader)
+			}
+		}
+
+		return nil
+	}
+}
+
+// MaxAge determines the maximum age (in seconds) between preflight requests. A
+// maximum of 10 minutes is allowed. An age above this value will default to 10
+// minutes.
+func MaxAge(age int) CORSOption {
+	return func(ch *cors) error {
+		// Maximum of 10 minutes.
+		if age > 600 {
+			age = 600
+		}
+
+		ch.maxAge = age
+		return nil
+	}
+}
+
+// IgnoreOptions causes the CORS middleware to ignore OPTIONS requests, instead
+// passing them through to the next handler. This is useful when your application
+// or framework has a pre-existing mechanism for responding to OPTIONS requests.
+func IgnoreOptions() CORSOption {
+	return func(ch *cors) error {
+		ch.ignoreOptions = true
+		return nil
+	}
+}
+
+// AllowCredentials can be used to specify that the user agent may pass
+// authentication details along with the request.
+func AllowCredentials() CORSOption {
+	return func(ch *cors) error {
+		ch.allowCredentials = true
+		return nil
+	}
+}
+
+func (ch *cors) isOriginAllowed(origin string) bool {
+	if origin == "" {
+		return false
+	}
+
+	if ch.allowedOriginValidator != nil {
+		return ch.allowedOriginValidator(origin)
+	}
+
+	if len(ch.allowedOrigins) == 0 {
+		return true
+	}
+
+	for _, allowedOrigin := range ch.allowedOrigins {
+		if allowedOrigin == origin || allowedOrigin == corsOriginMatchAll {
+			return true
+		}
+	}
+
+	return false
+}
+
+func (ch *cors) isMatch(needle string, haystack []string) bool {
+	for _, v := range haystack {
+		if v == needle {
+			return true
+		}
+	}
+
+	return false
+}

vendor/github.com/gorilla/handlers/doc.go

@@ -0,0 +1,9 @@
+/*
+Package handlers is a collection of handlers (aka "HTTP middleware") for use
+with Go's net/http package (or any framework supporting http.Handler).
+
+The package includes handlers for logging in standardised formats, compressing
+HTTP responses, validating content types and other useful tools for manipulating
+requests and responses.
+*/
+package handlers

vendor/github.com/gorilla/handlers/handlers.go

@@ -0,0 +1,147 @@
+// Copyright 2013 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package handlers
+
+import (
+	"bufio"
+	"fmt"
+	"net"
+	"net/http"
+	"sort"
+	"strings"
+)
+
+// MethodHandler is an http.Handler that dispatches to a handler whose key in the
+// MethodHandler's map matches the name of the HTTP request's method, eg: GET
+//
+// If the request's method is OPTIONS and OPTIONS is not a key in the map then
+// the handler responds with a status of 200 and sets the Allow header to a
+// comma-separated list of available methods.
+//
+// If the request's method doesn't match any of its keys the handler responds
+// with a status of HTTP 405 "Method Not Allowed" and sets the Allow header to a
+// comma-separated list of available methods.
+type MethodHandler map[string]http.Handler
+
+func (h MethodHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	if handler, ok := h[req.Method]; ok {
+		handler.ServeHTTP(w, req)
+	} else {
+		allow := []string{}
+		for k := range h {
+			allow = append(allow, k)
+		}
+		sort.Strings(allow)
+		w.Header().Set("Allow", strings.Join(allow, ", "))
+		if req.Method == "OPTIONS" {
+			w.WriteHeader(http.StatusOK)
+		} else {
+			http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+		}
+	}
+}
+
+// responseLogger is wrapper of http.ResponseWriter that keeps track of its HTTP
+// status code and body size
+type responseLogger struct {
+	w      http.ResponseWriter
+	status int
+	size   int
+}
+
+func (l *responseLogger) Write(b []byte) (int, error) {
+	size, err := l.w.Write(b)
+	l.size += size
+	return size, err
+}
+
+func (l *responseLogger) WriteHeader(s int) {
+	l.w.WriteHeader(s)
+	l.status = s
+}
+
+func (l *responseLogger) Status() int {
+	return l.status
+}
+
+func (l *responseLogger) Size() int {
+	return l.size
+}
+
+func (l *responseLogger) Hijack() (net.Conn, *bufio.ReadWriter, error) {
+	conn, rw, err := l.w.(http.Hijacker).Hijack()
+	if err == nil && l.status == 0 {
+		// The status will be StatusSwitchingProtocols if there was no error and
+		// WriteHeader has not been called yet
+		l.status = http.StatusSwitchingProtocols
+	}
+	return conn, rw, err
+}
+
+// isContentType validates the Content-Type header matches the supplied
+// contentType. That is, its type and subtype match.
+func isContentType(h http.Header, contentType string) bool {
+	ct := h.Get("Content-Type")
+	if i := strings.IndexRune(ct, ';'); i != -1 {
+		ct = ct[0:i]
+	}
+	return ct == contentType
+}
+
+// ContentTypeHandler wraps and returns a http.Handler, validating the request
+// content type is compatible with the contentTypes list. It writes a HTTP 415
+// error if that fails.
+//
+// Only PUT, POST, and PATCH requests are considered.
+func ContentTypeHandler(h http.Handler, contentTypes ...string) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if !(r.Method == "PUT" || r.Method == "POST" || r.Method == "PATCH") {
+			h.ServeHTTP(w, r)
+			return
+		}
+
+		for _, ct := range contentTypes {
+			if isContentType(r.Header, ct) {
+				h.ServeHTTP(w, r)
+				return
+			}
+		}
+		http.Error(w, fmt.Sprintf("Unsupported content type %q; expected one of %q", r.Header.Get("Content-Type"), contentTypes), http.StatusUnsupportedMediaType)
+	})
+}
+
+const (
+	// HTTPMethodOverrideHeader is a commonly used
+	// http header to override a request method.
+	HTTPMethodOverrideHeader = "X-HTTP-Method-Override"
+	// HTTPMethodOverrideFormKey is a commonly used
+	// HTML form key to override a request method.
+	HTTPMethodOverrideFormKey = "_method"
+)
+
+// HTTPMethodOverrideHandler wraps and returns a http.Handler which checks for
+// the X-HTTP-Method-Override header or the _method form key, and overrides (if
+// valid) request.Method with its value.
+//
+// This is especially useful for HTTP clients that don't support many http verbs.
+// It isn't secure to override e.g a GET to a POST, so only POST requests are
+// considered.  Likewise, the override method can only be a "write" method: PUT,
+// PATCH or DELETE.
+//
+// Form method takes precedence over header method.
+func HTTPMethodOverrideHandler(h http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.Method == "POST" {
+			om := r.FormValue(HTTPMethodOverrideFormKey)
+			if om == "" {
+				om = r.Header.Get(HTTPMethodOverrideHeader)
+			}
+			if om == "PUT" || om == "PATCH" || om == "DELETE" {
+				r.Method = om
+			}
+		}
+		h.ServeHTTP(w, r)
+	})
+}

vendor/github.com/gorilla/handlers/logging.go

@@ -0,0 +1,244 @@
+// Copyright 2013 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package handlers
+
+import (
+	"io"
+	"net"
+	"net/http"
+	"net/url"
+	"strconv"
+	"time"
+	"unicode/utf8"
+
+	"github.com/felixge/httpsnoop"
+)
+
+// Logging
+
+// LogFormatterParams is the structure any formatter will be handed when time to log comes
+type LogFormatterParams struct {
+	Request    *http.Request
+	URL        url.URL
+	TimeStamp  time.Time
+	StatusCode int
+	Size       int
+}
+
+// LogFormatter gives the signature of the formatter function passed to CustomLoggingHandler
+type LogFormatter func(writer io.Writer, params LogFormatterParams)
+
+// loggingHandler is the http.Handler implementation for LoggingHandlerTo and its
+// friends
+
+type loggingHandler struct {
+	writer    io.Writer
+	handler   http.Handler
+	formatter LogFormatter
+}
+
+func (h loggingHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	t := time.Now()
+	logger, w := makeLogger(w)
+	url := *req.URL
+
+	h.handler.ServeHTTP(w, req)
+	if req.MultipartForm != nil {
+		req.MultipartForm.RemoveAll()
+	}
+
+	params := LogFormatterParams{
+		Request:    req,
+		URL:        url,
+		TimeStamp:  t,
+		StatusCode: logger.Status(),
+		Size:       logger.Size(),
+	}
+
+	h.formatter(h.writer, params)
+}
+
+func makeLogger(w http.ResponseWriter) (*responseLogger, http.ResponseWriter) {
+	logger := &responseLogger{w: w, status: http.StatusOK}
+	return logger, httpsnoop.Wrap(w, httpsnoop.Hooks{
+		Write: func(httpsnoop.WriteFunc) httpsnoop.WriteFunc {
+			return logger.Write
+		},
+		WriteHeader: func(httpsnoop.WriteHeaderFunc) httpsnoop.WriteHeaderFunc {
+			return logger.WriteHeader
+		},
+	})
+}
+
+const lowerhex = "0123456789abcdef"
+
+func appendQuoted(buf []byte, s string) []byte {
+	var runeTmp [utf8.UTFMax]byte
+	for width := 0; len(s) > 0; s = s[width:] {
+		r := rune(s[0])
+		width = 1
+		if r >= utf8.RuneSelf {
+			r, width = utf8.DecodeRuneInString(s)
+		}
+		if width == 1 && r == utf8.RuneError {
+			buf = append(buf, `\x`...)
+			buf = append(buf, lowerhex[s[0]>>4])
+			buf = append(buf, lowerhex[s[0]&0xF])
+			continue
+		}
+		if r == rune('"') || r == '\\' { // always backslashed
+			buf = append(buf, '\\')
+			buf = append(buf, byte(r))
+			continue
+		}
+		if strconv.IsPrint(r) {
+			n := utf8.EncodeRune(runeTmp[:], r)
+			buf = append(buf, runeTmp[:n]...)
+			continue
+		}
+		switch r {
+		case '\a':
+			buf = append(buf, `\a`...)
+		case '\b':
+			buf = append(buf, `\b`...)
+		case '\f':
+			buf = append(buf, `\f`...)
+		case '\n':
+			buf = append(buf, `\n`...)
+		case '\r':
+			buf = append(buf, `\r`...)
+		case '\t':
+			buf = append(buf, `\t`...)
+		case '\v':
+			buf = append(buf, `\v`...)
+		default:
+			switch {
+			case r < ' ':
+				buf = append(buf, `\x`...)
+				buf = append(buf, lowerhex[s[0]>>4])
+				buf = append(buf, lowerhex[s[0]&0xF])
+			case r > utf8.MaxRune:
+				r = 0xFFFD
+				fallthrough
+			case r < 0x10000:
+				buf = append(buf, `\u`...)
+				for s := 12; s >= 0; s -= 4 {
+					buf = append(buf, lowerhex[r>>uint(s)&0xF])
+				}
+			default:
+				buf = append(buf, `\U`...)
+				for s := 28; s >= 0; s -= 4 {
+					buf = append(buf, lowerhex[r>>uint(s)&0xF])
+				}
+			}
+		}
+	}
+	return buf
+}
+
+// buildCommonLogLine builds a log entry for req in Apache Common Log Format.
+// ts is the timestamp with which the entry should be logged.
+// status and size are used to provide the response HTTP status and size.
+func buildCommonLogLine(req *http.Request, url url.URL, ts time.Time, status int, size int) []byte {
+	username := "-"
+	if url.User != nil {
+		if name := url.User.Username(); name != "" {
+			username = name
+		}
+	}
+
+	host, _, err := net.SplitHostPort(req.RemoteAddr)
+	if err != nil {
+		host = req.RemoteAddr
+	}
+
+	uri := req.RequestURI
+
+	// Requests using the CONNECT method over HTTP/2.0 must use
+	// the authority field (aka r.Host) to identify the target.
+	// Refer: https://httpwg.github.io/specs/rfc7540.html#CONNECT
+	if req.ProtoMajor == 2 && req.Method == "CONNECT" {
+		uri = req.Host
+	}
+	if uri == "" {
+		uri = url.RequestURI()
+	}
+
+	buf := make([]byte, 0, 3*(len(host)+len(username)+len(req.Method)+len(uri)+len(req.Proto)+50)/2)
+	buf = append(buf, host...)
+	buf = append(buf, " - "...)
+	buf = append(buf, username...)
+	buf = append(buf, " ["...)
+	buf = append(buf, ts.Format("02/Jan/2006:15:04:05 -0700")...)
+	buf = append(buf, `] "`...)
+	buf = append(buf, req.Method...)
+	buf = append(buf, " "...)
+	buf = appendQuoted(buf, uri)
+	buf = append(buf, " "...)
+	buf = append(buf, req.Proto...)
+	buf = append(buf, `" `...)
+	buf = append(buf, strconv.Itoa(status)...)
+	buf = append(buf, " "...)
+	buf = append(buf, strconv.Itoa(size)...)
+	return buf
+}
+
+// writeLog writes a log entry for req to w in Apache Common Log Format.
+// ts is the timestamp with which the entry should be logged.
+// status and size are used to provide the response HTTP status and size.
+func writeLog(writer io.Writer, params LogFormatterParams) {
+	buf := buildCommonLogLine(params.Request, params.URL, params.TimeStamp, params.StatusCode, params.Size)
+	buf = append(buf, '\n')
+	writer.Write(buf)
+}
+
+// writeCombinedLog writes a log entry for req to w in Apache Combined Log Format.
+// ts is the timestamp with which the entry should be logged.
+// status and size are used to provide the response HTTP status and size.
+func writeCombinedLog(writer io.Writer, params LogFormatterParams) {
+	buf := buildCommonLogLine(params.Request, params.URL, params.TimeStamp, params.StatusCode, params.Size)
+	buf = append(buf, ` "`...)
+	buf = appendQuoted(buf, params.Request.Referer())
+	buf = append(buf, `" "`...)
+	buf = appendQuoted(buf, params.Request.UserAgent())
+	buf = append(buf, '"', '\n')
+	writer.Write(buf)
+}
+
+// CombinedLoggingHandler return a http.Handler that wraps h and logs requests to out in
+// Apache Combined Log Format.
+//
+// See http://httpd.apache.org/docs/2.2/logs.html#combined for a description of this format.
+//
+// LoggingHandler always sets the ident field of the log to -
+func CombinedLoggingHandler(out io.Writer, h http.Handler) http.Handler {
+	return loggingHandler{out, h, writeCombinedLog}
+}
+
+// LoggingHandler return a http.Handler that wraps h and logs requests to out in
+// Apache Common Log Format (CLF).
+//
+// See http://httpd.apache.org/docs/2.2/logs.html#common for a description of this format.
+//
+// LoggingHandler always sets the ident field of the log to -
+//
+// Example:
+//
+//  r := mux.NewRouter()
+//  r.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+//  	w.Write([]byte("This is a catch-all route"))
+//  })
+//  loggedRouter := handlers.LoggingHandler(os.Stdout, r)
+//  http.ListenAndServe(":1123", loggedRouter)
+//
+func LoggingHandler(out io.Writer, h http.Handler) http.Handler {
+	return loggingHandler{out, h, writeLog}
+}
+
+// CustomLoggingHandler provides a way to supply a custom log formatter
+// while taking advantage of the mechanisms in this package
+func CustomLoggingHandler(out io.Writer, h http.Handler, f LogFormatter) http.Handler {
+	return loggingHandler{out, h, f}
+}

vendor/github.com/gorilla/handlers/proxy_headers.go

@@ -0,0 +1,120 @@
+package handlers
+
+import (
+	"net/http"
+	"regexp"
+	"strings"
+)
+
+var (
+	// De-facto standard header keys.
+	xForwardedFor    = http.CanonicalHeaderKey("X-Forwarded-For")
+	xForwardedHost   = http.CanonicalHeaderKey("X-Forwarded-Host")
+	xForwardedProto  = http.CanonicalHeaderKey("X-Forwarded-Proto")
+	xForwardedScheme = http.CanonicalHeaderKey("X-Forwarded-Scheme")
+	xRealIP          = http.CanonicalHeaderKey("X-Real-IP")
+)
+
+var (
+	// RFC7239 defines a new "Forwarded: " header designed to replace the
+	// existing use of X-Forwarded-* headers.
+	// e.g. Forwarded: for=192.0.2.60;proto=https;by=203.0.113.43
+	forwarded = http.CanonicalHeaderKey("Forwarded")
+	// Allows for a sub-match of the first value after 'for=' to the next
+	// comma, semi-colon or space. The match is case-insensitive.
+	forRegex = regexp.MustCompile(`(?i)(?:for=)([^(;|,| )]+)`)
+	// Allows for a sub-match for the first instance of scheme (http|https)
+	// prefixed by 'proto='. The match is case-insensitive.
+	protoRegex = regexp.MustCompile(`(?i)(?:proto=)(https|http)`)
+)
+
+// ProxyHeaders inspects common reverse proxy headers and sets the corresponding
+// fields in the HTTP request struct. These are X-Forwarded-For and X-Real-IP
+// for the remote (client) IP address, X-Forwarded-Proto or X-Forwarded-Scheme
+// for the scheme (http|https), X-Forwarded-Host for the host and the RFC7239
+// Forwarded header, which may include both client IPs and schemes.
+//
+// NOTE: This middleware should only be used when behind a reverse
+// proxy like nginx, HAProxy or Apache. Reverse proxies that don't (or are
+// configured not to) strip these headers from client requests, or where these
+// headers are accepted "as is" from a remote client (e.g. when Go is not behind
+// a proxy), can manifest as a vulnerability if your application uses these
+// headers for validating the 'trustworthiness' of a request.
+func ProxyHeaders(h http.Handler) http.Handler {
+	fn := func(w http.ResponseWriter, r *http.Request) {
+		// Set the remote IP with the value passed from the proxy.
+		if fwd := getIP(r); fwd != "" {
+			r.RemoteAddr = fwd
+		}
+
+		// Set the scheme (proto) with the value passed from the proxy.
+		if scheme := getScheme(r); scheme != "" {
+			r.URL.Scheme = scheme
+		}
+		// Set the host with the value passed by the proxy
+		if r.Header.Get(xForwardedHost) != "" {
+			r.Host = r.Header.Get(xForwardedHost)
+		}
+		// Call the next handler in the chain.
+		h.ServeHTTP(w, r)
+	}
+
+	return http.HandlerFunc(fn)
+}
+
+// getIP retrieves the IP from the X-Forwarded-For, X-Real-IP and RFC7239
+// Forwarded headers (in that order).
+func getIP(r *http.Request) string {
+	var addr string
+
+	if fwd := r.Header.Get(xForwardedFor); fwd != "" {
+		// Only grab the first (client) address. Note that '192.168.0.1,
+		// 10.1.1.1' is a valid key for X-Forwarded-For where addresses after
+		// the first may represent forwarding proxies earlier in the chain.
+		s := strings.Index(fwd, ", ")
+		if s == -1 {
+			s = len(fwd)
+		}
+		addr = fwd[:s]
+	} else if fwd := r.Header.Get(xRealIP); fwd != "" {
+		// X-Real-IP should only contain one IP address (the client making the
+		// request).
+		addr = fwd
+	} else if fwd := r.Header.Get(forwarded); fwd != "" {
+		// match should contain at least two elements if the protocol was
+		// specified in the Forwarded header. The first element will always be
+		// the 'for=' capture, which we ignore. In the case of multiple IP
+		// addresses (for=8.8.8.8, 8.8.4.4,172.16.1.20 is valid) we only
+		// extract the first, which should be the client IP.
+		if match := forRegex.FindStringSubmatch(fwd); len(match) > 1 {
+			// IPv6 addresses in Forwarded headers are quoted-strings. We strip
+			// these quotes.
+			addr = strings.Trim(match[1], `"`)
+		}
+	}
+
+	return addr
+}
+
+// getScheme retrieves the scheme from the X-Forwarded-Proto and RFC7239
+// Forwarded headers (in that order).
+func getScheme(r *http.Request) string {
+	var scheme string
+
+	// Retrieve the scheme from X-Forwarded-Proto.
+	if proto := r.Header.Get(xForwardedProto); proto != "" {
+		scheme = strings.ToLower(proto)
+	} else if proto = r.Header.Get(xForwardedScheme); proto != "" {
+		scheme = strings.ToLower(proto)
+	} else if proto = r.Header.Get(forwarded); proto != "" {
+		// match should contain at least two elements if the protocol was
+		// specified in the Forwarded header. The first element will always be
+		// the 'proto=' capture, which we ignore. In the case of multiple proto
+		// parameters (invalid) we only extract the first.
+		if match := protoRegex.FindStringSubmatch(proto); len(match) > 1 {
+			scheme = strings.ToLower(match[1])
+		}
+	}
+
+	return scheme
+}

vendor/github.com/gorilla/handlers/recovery.go

@@ -0,0 +1,96 @@
+package handlers
+
+import (
+	"log"
+	"net/http"
+	"runtime/debug"
+)
+
+// RecoveryHandlerLogger is an interface used by the recovering handler to print logs.
+type RecoveryHandlerLogger interface {
+	Println(...interface{})
+}
+
+type recoveryHandler struct {
+	handler    http.Handler
+	logger     RecoveryHandlerLogger
+	printStack bool
+}
+
+// RecoveryOption provides a functional approach to define
+// configuration for a handler; such as setting the logging
+// whether or not to print stack traces on panic.
+type RecoveryOption func(http.Handler)
+
+func parseRecoveryOptions(h http.Handler, opts ...RecoveryOption) http.Handler {
+	for _, option := range opts {
+		option(h)
+	}
+
+	return h
+}
+
+// RecoveryHandler is HTTP middleware that recovers from a panic,
+// logs the panic, writes http.StatusInternalServerError, and
+// continues to the next handler.
+//
+// Example:
+//
+//  r := mux.NewRouter()
+//  r.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+//  	panic("Unexpected error!")
+//  })
+//
+//  http.ListenAndServe(":1123", handlers.RecoveryHandler()(r))
+func RecoveryHandler(opts ...RecoveryOption) func(h http.Handler) http.Handler {
+	return func(h http.Handler) http.Handler {
+		r := &recoveryHandler{handler: h}
+		return parseRecoveryOptions(r, opts...)
+	}
+}
+
+// RecoveryLogger is a functional option to override
+// the default logger
+func RecoveryLogger(logger RecoveryHandlerLogger) RecoveryOption {
+	return func(h http.Handler) {
+		r := h.(*recoveryHandler)
+		r.logger = logger
+	}
+}
+
+// PrintRecoveryStack is a functional option to enable
+// or disable printing stack traces on panic.
+func PrintRecoveryStack(print bool) RecoveryOption {
+	return func(h http.Handler) {
+		r := h.(*recoveryHandler)
+		r.printStack = print
+	}
+}
+
+func (h recoveryHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	defer func() {
+		if err := recover(); err != nil {
+			w.WriteHeader(http.StatusInternalServerError)
+			h.log(err)
+		}
+	}()
+
+	h.handler.ServeHTTP(w, req)
+}
+
+func (h recoveryHandler) log(v ...interface{}) {
+	if h.logger != nil {
+		h.logger.Println(v...)
+	} else {
+		log.Println(v...)
+	}
+
+	if h.printStack {
+		stack := string(debug.Stack())
+		if h.logger != nil {
+			h.logger.Println(stack)
+		} else {
+			log.Println(stack)
+		}
+	}
+}

vendor/github.com/julienschmidt/httprouter/.travis.yml

@@ -0,0 +1,18 @@
+sudo: false
+language: go
+go:
+  - 1.7.x
+  - 1.8.x
+  - 1.9.x
+  - 1.10.x
+  - 1.11.x
+  - 1.12.x
+  - 1.13.x
+  - master
+before_install:
+  - go get github.com/mattn/goveralls
+script:
+  - go test -v -covermode=count -coverprofile=coverage.out
+  - go vet ./...
+  - test -z "$(gofmt -d -s . | tee /dev/stderr)"
+  - $HOME/gopath/bin/goveralls  -coverprofile=coverage.out -service=travis-ci

vendor/github.com/julienschmidt/httprouter/LICENSE

@@ -0,0 +1,29 @@
+BSD 3-Clause License
+
+Copyright (c) 2013, Julien Schmidt
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+1. Redistributions of source code must retain the above copyright notice, this
+   list of conditions and the following disclaimer.
+
+2. Redistributions in binary form must reproduce the above copyright notice,
+   this list of conditions and the following disclaimer in the documentation
+   and/or other materials provided with the distribution.
+
+3. Neither the name of the copyright holder nor the names of its
+   contributors may be used to endorse or promote products derived from
+   this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/github.com/julienschmidt/httprouter/README.md

@@ -0,0 +1,300 @@
+# HttpRouter [![Build Status](https://travis-ci.org/julienschmidt/httprouter.svg?branch=master)](https://travis-ci.org/julienschmidt/httprouter) [![Coverage Status](https://coveralls.io/repos/github/julienschmidt/httprouter/badge.svg?branch=master)](https://coveralls.io/github/julienschmidt/httprouter?branch=master) [![GoDoc](https://godoc.org/github.com/julienschmidt/httprouter?status.svg)](http://godoc.org/github.com/julienschmidt/httprouter)
+
+HttpRouter is a lightweight high performance HTTP request router (also called *multiplexer* or just *mux* for short) for [Go](https://golang.org/).
+
+In contrast to the [default mux](https://golang.org/pkg/net/http/#ServeMux) of Go's `net/http` package, this router supports variables in the routing pattern and matches against the request method. It also scales better.
+
+The router is optimized for high performance and a small memory footprint. It scales well even with very long paths and a large number of routes. A compressing dynamic trie (radix tree) structure is used for efficient matching.
+
+## Features
+
+**Only explicit matches:** With other routers, like [`http.ServeMux`](https://golang.org/pkg/net/http/#ServeMux), a requested URL path could match multiple patterns. Therefore they have some awkward pattern priority rules, like *longest match* or *first registered, first matched*. By design of this router, a request can only match exactly one or no route. As a result, there are also no unintended matches, which makes it great for SEO and improves the user experience.
+
+**Stop caring about trailing slashes:** Choose the URL style you like, the router automatically redirects the client if a trailing slash is missing or if there is one extra. Of course it only does so, if the new path has a handler. If you don't like it, you can [turn off this behavior](https://godoc.org/github.com/julienschmidt/httprouter#Router.RedirectTrailingSlash).
+
+**Path auto-correction:** Besides detecting the missing or additional trailing slash at no extra cost, the router can also fix wrong cases and remove superfluous path elements (like `../` or `//`). Is [CAPTAIN CAPS LOCK](http://www.urbandictionary.com/define.php?term=Captain+Caps+Lock) one of your users? HttpRouter can help him by making a case-insensitive look-up and redirecting him to the correct URL.
+
+**Parameters in your routing pattern:** Stop parsing the requested URL path, just give the path segment a name and the router delivers the dynamic value to you. Because of the design of the router, path parameters are very cheap.
+
+**Zero Garbage:** The matching and dispatching process generates zero bytes of garbage. The only heap allocations that are made are building the slice of the key-value pairs for path parameters, and building new context and request objects (the latter only in the standard `Handler`/`HandlerFunc` API). In the 3-argument API, if the request path contains no parameters not a single heap allocation is necessary.
+
+**Best Performance:** [Benchmarks speak for themselves](https://github.com/julienschmidt/go-http-routing-benchmark). See below for technical details of the implementation.
+
+**No more server crashes:** You can set a [Panic handler](https://godoc.org/github.com/julienschmidt/httprouter#Router.PanicHandler) to deal with panics occurring during handling a HTTP request. The router then recovers and lets the `PanicHandler` log what happened and deliver a nice error page.
+
+**Perfect for APIs:** The router design encourages to build sensible, hierarchical RESTful APIs. Moreover it has built-in native support for [OPTIONS requests](http://zacstewart.com/2012/04/14/http-options-method.html) and `405 Method Not Allowed` replies.
+
+Of course you can also set **custom [`NotFound`](https://godoc.org/github.com/julienschmidt/httprouter#Router.NotFound) and  [`MethodNotAllowed`](https://godoc.org/github.com/julienschmidt/httprouter#Router.MethodNotAllowed) handlers** and [**serve static files**](https://godoc.org/github.com/julienschmidt/httprouter#Router.ServeFiles).
+
+## Usage
+
+This is just a quick introduction, view the [GoDoc](http://godoc.org/github.com/julienschmidt/httprouter) for details.
+
+Let's start with a trivial example:
+
+```go
+package main
+
+import (
+    "fmt"
+    "net/http"
+    "log"
+
+    "github.com/julienschmidt/httprouter"
+)
+
+func Index(w http.ResponseWriter, r *http.Request, _ httprouter.Params) {
+    fmt.Fprint(w, "Welcome!\n")
+}
+
+func Hello(w http.ResponseWriter, r *http.Request, ps httprouter.Params) {
+    fmt.Fprintf(w, "hello, %s!\n", ps.ByName("name"))
+}
+
+func main() {
+    router := httprouter.New()
+    router.GET("/", Index)
+    router.GET("/hello/:name", Hello)
+
+    log.Fatal(http.ListenAndServe(":8080", router))
+}
+```
+
+### Named parameters
+
+As you can see, `:name` is a *named parameter*. The values are accessible via `httprouter.Params`, which is just a slice of `httprouter.Param`s. You can get the value of a parameter either by its index in the slice, or by using the `ByName(name)` method: `:name` can be retrieved by `ByName("name")`.
+
+When using a `http.Handler` (using `router.Handler` or `http.HandlerFunc`) instead of HttpRouter's handle API using a 3rd function parameter, the named parameters are stored in the `request.Context`. See more below under [Why doesn't this work with http.Handler?](#why-doesnt-this-work-with-httphandler).
+
+Named parameters only match a single path segment:
+
+```
+Pattern: /user/:user
+
+ /user/gordon              match
+ /user/you                 match
+ /user/gordon/profile      no match
+ /user/                    no match
+```
+
+**Note:** Since this router has only explicit matches, you can not register static routes and parameters for the same path segment. For example you can not register the patterns `/user/new` and `/user/:user` for the same request method at the same time. The routing of different request methods is independent from each other.
+
+### Catch-All parameters
+
+The second type are *catch-all* parameters and have the form `*name`. Like the name suggests, they match everything. Therefore they must always be at the **end** of the pattern:
+
+```
+Pattern: /src/*filepath
+
+ /src/                     match
+ /src/somefile.go          match
+ /src/subdir/somefile.go   match
+```
+
+## How does it work?
+
+The router relies on a tree structure which makes heavy use of *common prefixes*, it is basically a *compact* [*prefix tree*](https://en.wikipedia.org/wiki/Trie) (or just [*Radix tree*](https://en.wikipedia.org/wiki/Radix_tree)). Nodes with a common prefix also share a common parent. Here is a short example what the routing tree for the `GET` request method could look like:
+
+```
+Priority   Path             Handle
+9          \                *<1>
+3          ├s               nil
+2          |├earch\         *<2>
+1          |└upport\        *<3>
+2          ├blog\           *<4>
+1          |    └:post      nil
+1          |         └\     *<5>
+2          ├about-us\       *<6>
+1          |        └team\  *<7>
+1          └contact\        *<8>
+```
+
+Every `*<num>` represents the memory address of a handler function (a pointer). If you follow a path trough the tree from the root to the leaf, you get the complete route path, e.g `\blog\:post\`, where `:post` is just a placeholder ([*parameter*](#named-parameters)) for an actual post name. Unlike hash-maps, a tree structure also allows us to use dynamic parts like the `:post` parameter, since we actually match against the routing patterns instead of just comparing hashes. [As benchmarks show](https://github.com/julienschmidt/go-http-routing-benchmark), this works very well and efficient.
+
+Since URL paths have a hierarchical structure and make use only of a limited set of characters (byte values), it is very likely that there are a lot of common prefixes. This allows us to easily reduce the routing into ever smaller problems. Moreover the router manages a separate tree for every request method. For one thing it is more space efficient than holding a method->handle map in every single node, it also allows us to greatly reduce the routing problem before even starting the look-up in the prefix-tree.
+
+For even better scalability, the child nodes on each tree level are ordered by priority, where the priority is just the number of handles registered in sub nodes (children, grandchildren, and so on..). This helps in two ways:
+
+1. Nodes which are part of the most routing paths are evaluated first. This helps to make as much routes as possible to be reachable as fast as possible.
+2. It is some sort of cost compensation. The longest reachable path (highest cost) can always be evaluated first. The following scheme visualizes the tree structure. Nodes are evaluated from top to bottom and from left to right.
+
+```
+├------------
+├---------
+├-----
+├----
+├--
+├--
+└-
+```
+
+## Why doesn't this work with `http.Handler`?
+
+**It does!** The router itself implements the `http.Handler` interface. Moreover the router provides convenient [adapters for `http.Handler`](https://godoc.org/github.com/julienschmidt/httprouter#Router.Handler)s and [`http.HandlerFunc`](https://godoc.org/github.com/julienschmidt/httprouter#Router.HandlerFunc)s which allows them to be used as a [`httprouter.Handle`](https://godoc.org/github.com/julienschmidt/httprouter#Router.Handle) when registering a route.
+
+Named parameters can be accessed `request.Context`:
+
+```go
+func Hello(w http.ResponseWriter, r *http.Request) {
+    params := httprouter.ParamsFromContext(r.Context())
+
+    fmt.Fprintf(w, "hello, %s!\n", params.ByName("name"))
+}
+```
+
+Alternatively, one can also use `params := r.Context().Value(httprouter.ParamsKey)` instead of the helper function.
+
+Just try it out for yourself, the usage of HttpRouter is very straightforward. The package is compact and minimalistic, but also probably one of the easiest routers to set up.
+
+## Automatic OPTIONS responses and CORS
+
+One might wish to modify automatic responses to OPTIONS requests, e.g. to support [CORS preflight requests](https://developer.mozilla.org/en-US/docs/Glossary/preflight_request) or to set other headers.
+This can be achieved using the [`Router.GlobalOPTIONS`](https://godoc.org/github.com/julienschmidt/httprouter#Router.GlobalOPTIONS) handler:
+
+```go
+router.GlobalOPTIONS = http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+    if r.Header.Get("Access-Control-Request-Method") != "" {
+        // Set CORS headers
+        header := w.Header()
+        header.Set("Access-Control-Allow-Methods", r.Header.Get("Allow"))
+        header.Set("Access-Control-Allow-Origin", "*")
+    }
+
+    // Adjust status code to 204
+    w.WriteHeader(http.StatusNoContent)
+})
+```
+
+## Where can I find Middleware *X*?
+
+This package just provides a very efficient request router with a few extra features. The router is just a [`http.Handler`](https://golang.org/pkg/net/http/#Handler), you can chain any http.Handler compatible middleware before the router, for example the [Gorilla handlers](http://www.gorillatoolkit.org/pkg/handlers). Or you could [just write your own](https://justinas.org/writing-http-middleware-in-go/), it's very easy!
+
+Alternatively, you could try [a web framework based on HttpRouter](#web-frameworks-based-on-httprouter).
+
+### Multi-domain / Sub-domains
+
+Here is a quick example: Does your server serve multiple domains / hosts?
+You want to use sub-domains?
+Define a router per host!
+
+```go
+// We need an object that implements the http.Handler interface.
+// Therefore we need a type for which we implement the ServeHTTP method.
+// We just use a map here, in which we map host names (with port) to http.Handlers
+type HostSwitch map[string]http.Handler
+
+// Implement the ServeHTTP method on our new type
+func (hs HostSwitch) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	// Check if a http.Handler is registered for the given host.
+	// If yes, use it to handle the request.
+	if handler := hs[r.Host]; handler != nil {
+		handler.ServeHTTP(w, r)
+	} else {
+		// Handle host names for which no handler is registered
+		http.Error(w, "Forbidden", 403) // Or Redirect?
+	}
+}
+
+func main() {
+	// Initialize a router as usual
+	router := httprouter.New()
+	router.GET("/", Index)
+	router.GET("/hello/:name", Hello)
+
+	// Make a new HostSwitch and insert the router (our http handler)
+	// for example.com and port 12345
+	hs := make(HostSwitch)
+	hs["example.com:12345"] = router
+
+	// Use the HostSwitch to listen and serve on port 12345
+	log.Fatal(http.ListenAndServe(":12345", hs))
+}
+```
+
+### Basic Authentication
+
+Another quick example: Basic Authentication (RFC 2617) for handles:
+
+```go
+package main
+
+import (
+	"fmt"
+	"log"
+	"net/http"
+
+	"github.com/julienschmidt/httprouter"
+)
+
+func BasicAuth(h httprouter.Handle, requiredUser, requiredPassword string) httprouter.Handle {
+	return func(w http.ResponseWriter, r *http.Request, ps httprouter.Params) {
+		// Get the Basic Authentication credentials
+		user, password, hasAuth := r.BasicAuth()
+
+		if hasAuth && user == requiredUser && password == requiredPassword {
+			// Delegate request to the given handle
+			h(w, r, ps)
+		} else {
+			// Request Basic Authentication otherwise
+			w.Header().Set("WWW-Authenticate", "Basic realm=Restricted")
+			http.Error(w, http.StatusText(http.StatusUnauthorized), http.StatusUnauthorized)
+		}
+	}
+}
+
+func Index(w http.ResponseWriter, r *http.Request, _ httprouter.Params) {
+	fmt.Fprint(w, "Not protected!\n")
+}
+
+func Protected(w http.ResponseWriter, r *http.Request, _ httprouter.Params) {
+	fmt.Fprint(w, "Protected!\n")
+}
+
+func main() {
+	user := "gordon"
+	pass := "secret!"
+
+	router := httprouter.New()
+	router.GET("/", Index)
+	router.GET("/protected/", BasicAuth(Protected, user, pass))
+
+	log.Fatal(http.ListenAndServe(":8080", router))
+}
+```
+
+## Chaining with the NotFound handler
+
+**NOTE: It might be required to set [`Router.HandleMethodNotAllowed`](https://godoc.org/github.com/julienschmidt/httprouter#Router.HandleMethodNotAllowed) to `false` to avoid problems.**
+
+You can use another [`http.Handler`](https://golang.org/pkg/net/http/#Handler), for example another router, to handle requests which could not be matched by this router by using the [`Router.NotFound`](https://godoc.org/github.com/julienschmidt/httprouter#Router.NotFound) handler. This allows chaining.
+
+### Static files
+
+The `NotFound` handler can for example be used to serve static files from the root path `/` (like an `index.html` file along with other assets):
+
+```go
+// Serve static files from the ./public directory
+router.NotFound = http.FileServer(http.Dir("public"))
+```
+
+But this approach sidesteps the strict core rules of this router to avoid routing problems. A cleaner approach is to use a distinct sub-path for serving files, like `/static/*filepath` or `/files/*filepath`.
+
+## Web Frameworks based on HttpRouter
+
+If the HttpRouter is a bit too minimalistic for you, you might try one of the following more high-level 3rd-party web frameworks building upon the HttpRouter package:
+
+* [Ace](https://github.com/plimble/ace): Blazing fast Go Web Framework
+* [api2go](https://github.com/manyminds/api2go): A JSON API Implementation for Go
+* [Gin](https://github.com/gin-gonic/gin): Features a martini-like API with much better performance
+* [Goat](https://github.com/bahlo/goat): A minimalistic REST API server in Go
+* [goMiddlewareChain](https://github.com/TobiEiss/goMiddlewareChain): An express.js-like-middleware-chain
+* [Hikaru](https://github.com/najeira/hikaru): Supports standalone and Google AppEngine
+* [Hitch](https://github.com/nbio/hitch): Hitch ties httprouter, [httpcontext](https://github.com/nbio/httpcontext), and middleware up in a bow
+* [httpway](https://github.com/corneldamian/httpway): Simple middleware extension with context for httprouter and a server with gracefully shutdown support
+* [kami](https://github.com/guregu/kami): A tiny web framework using x/net/context
+* [Medeina](https://github.com/imdario/medeina): Inspired by Ruby's Roda and Cuba
+* [Neko](https://github.com/rocwong/neko): A lightweight web application framework for Golang
+* [pbgo](https://github.com/chai2010/pbgo): pbgo is a mini RPC/REST framework based on Protobuf
+* [River](https://github.com/abiosoft/river): River is a simple and lightweight REST server
+* [siesta](https://github.com/VividCortex/siesta): Composable HTTP handlers with contexts
+* [xmux](https://github.com/rs/xmux): xmux is a httprouter fork on top of xhandler (net/context aware)

vendor/github.com/julienschmidt/httprouter/path.go

@@ -0,0 +1,123 @@
+// Copyright 2013 Julien Schmidt. All rights reserved.
+// Based on the path package, Copyright 2009 The Go Authors.
+// Use of this source code is governed by a BSD-style license that can be found
+// in the LICENSE file.
+
+package httprouter
+
+// CleanPath is the URL version of path.Clean, it returns a canonical URL path
+// for p, eliminating . and .. elements.
+//
+// The following rules are applied iteratively until no further processing can
+// be done:
+//	1. Replace multiple slashes with a single slash.
+//	2. Eliminate each . path name element (the current directory).
+//	3. Eliminate each inner .. path name element (the parent directory)
+//	   along with the non-.. element that precedes it.
+//	4. Eliminate .. elements that begin a rooted path:
+//	   that is, replace "/.." by "/" at the beginning of a path.
+//
+// If the result of this process is an empty string, "/" is returned
+func CleanPath(p string) string {
+	// Turn empty string into "/"
+	if p == "" {
+		return "/"
+	}
+
+	n := len(p)
+	var buf []byte
+
+	// Invariants:
+	//      reading from path; r is index of next byte to process.
+	//      writing to buf; w is index of next byte to write.
+
+	// path must start with '/'
+	r := 1
+	w := 1
+
+	if p[0] != '/' {
+		r = 0
+		buf = make([]byte, n+1)
+		buf[0] = '/'
+	}
+
+	trailing := n > 1 && p[n-1] == '/'
+
+	// A bit more clunky without a 'lazybuf' like the path package, but the loop
+	// gets completely inlined (bufApp). So in contrast to the path package this
+	// loop has no expensive function calls (except 1x make)
+
+	for r < n {
+		switch {
+		case p[r] == '/':
+			// empty path element, trailing slash is added after the end
+			r++
+
+		case p[r] == '.' && r+1 == n:
+			trailing = true
+			r++
+
+		case p[r] == '.' && p[r+1] == '/':
+			// . element
+			r += 2
+
+		case p[r] == '.' && p[r+1] == '.' && (r+2 == n || p[r+2] == '/'):
+			// .. element: remove to last /
+			r += 3
+
+			if w > 1 {
+				// can backtrack
+				w--
+
+				if buf == nil {
+					for w > 1 && p[w] != '/' {
+						w--
+					}
+				} else {
+					for w > 1 && buf[w] != '/' {
+						w--
+					}
+				}
+			}
+
+		default:
+			// real path element.
+			// add slash if needed
+			if w > 1 {
+				bufApp(&buf, p, w, '/')
+				w++
+			}
+
+			// copy element
+			for r < n && p[r] != '/' {
+				bufApp(&buf, p, w, p[r])
+				w++
+				r++
+			}
+		}
+	}
+
+	// re-append trailing slash
+	if trailing && w > 1 {
+		bufApp(&buf, p, w, '/')
+		w++
+	}
+
+	if buf == nil {
+		return p[:w]
+	}
+	return string(buf[:w])
+}
+
+// internal helper to lazily create a buffer if necessary
+func bufApp(buf *[]byte, s string, w int, c byte) {
+	if *buf == nil {
+		if s[w] == c {
+			return
+		}
+
+		*buf = make([]byte, len(s))
+		copy(*buf, s[:w])
+	}
+	(*buf)[w] = c
+}

vendor/github.com/julienschmidt/httprouter/router.go

@@ -0,0 +1,452 @@
+// Copyright 2013 Julien Schmidt. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be found
+// in the LICENSE file.
+
+// Package httprouter is a trie based high performance HTTP request router.
+//
+// A trivial example is:
+//
+//  package main
+//
+//  import (
+//      "fmt"
+//      "github.com/julienschmidt/httprouter"
+//      "net/http"
+//      "log"
+//  )
+//
+//  func Index(w http.ResponseWriter, r *http.Request, _ httprouter.Params) {
+//      fmt.Fprint(w, "Welcome!\n")
+//  }
+//
+//  func Hello(w http.ResponseWriter, r *http.Request, ps httprouter.Params) {
+//      fmt.Fprintf(w, "hello, %s!\n", ps.ByName("name"))
+//  }
+//
+//  func main() {
+//      router := httprouter.New()
+//      router.GET("/", Index)
+//      router.GET("/hello/:name", Hello)
+//
+//      log.Fatal(http.ListenAndServe(":8080", router))
+//  }
+//
+// The router matches incoming requests by the request method and the path.
+// If a handle is registered for this path and method, the router delegates the
+// request to that function.
+// For the methods GET, POST, PUT, PATCH and DELETE shortcut functions exist to
+// register handles, for all other methods router.Handle can be used.
+//
+// The registered path, against which the router matches incoming requests, can
+// contain two types of parameters:
+//  Syntax    Type
+//  :name     named parameter
+//  *name     catch-all parameter
+//
+// Named parameters are dynamic path segments. They match anything until the
+// next '/' or the path end:
+//  Path: /blog/:category/:post
+//
+//  Requests:
+//   /blog/go/request-routers            match: category="go", post="request-routers"
+//   /blog/go/request-routers/           no match, but the router would redirect
+//   /blog/go/                           no match
+//   /blog/go/request-routers/comments   no match
+//
+// Catch-all parameters match anything until the path end, including the
+// directory index (the '/' before the catch-all). Since they match anything
+// until the end, catch-all parameters must always be the final path element.
+//  Path: /files/*filepath
+//
+//  Requests:
+//   /files/                             match: filepath="/"
+//   /files/LICENSE                      match: filepath="/LICENSE"
+//   /files/templates/article.html       match: filepath="/templates/article.html"
+//   /files                              no match, but the router would redirect
+//
+// The value of parameters is saved as a slice of the Param struct, consisting
+// each of a key and a value. The slice is passed to the Handle func as a third
+// parameter.
+// There are two ways to retrieve the value of a parameter:
+//  // by the name of the parameter
+//  user := ps.ByName("user") // defined by :user or *user
+//
+//  // by the index of the parameter. This way you can also get the name (key)
+//  thirdKey   := ps[2].Key   // the name of the 3rd parameter
+//  thirdValue := ps[2].Value // the value of the 3rd parameter
+package httprouter
+
+import (
+	"context"
+	"net/http"
+	"strings"
+)
+
+// Handle is a function that can be registered to a route to handle HTTP
+// requests. Like http.HandlerFunc, but has a third parameter for the values of
+// wildcards (variables).
+type Handle func(http.ResponseWriter, *http.Request, Params)
+
+// Param is a single URL parameter, consisting of a key and a value.
+type Param struct {
+	Key   string
+	Value string
+}
+
+// Params is a Param-slice, as returned by the router.
+// The slice is ordered, the first URL parameter is also the first slice value.
+// It is therefore safe to read values by the index.
+type Params []Param
+
+// ByName returns the value of the first Param which key matches the given name.
+// If no matching Param is found, an empty string is returned.
+func (ps Params) ByName(name string) string {
+	for i := range ps {
+		if ps[i].Key == name {
+			return ps[i].Value
+		}
+	}
+	return ""
+}
+
+type paramsKey struct{}
+
+// ParamsKey is the request context key under which URL params are stored.
+var ParamsKey = paramsKey{}
+
+// ParamsFromContext pulls the URL parameters from a request context,
+// or returns nil if none are present.
+func ParamsFromContext(ctx context.Context) Params {
+	p, _ := ctx.Value(ParamsKey).(Params)
+	return p
+}
+
+// Router is a http.Handler which can be used to dispatch requests to different
+// handler functions via configurable routes
+type Router struct {
+	trees map[string]*node
+
+	// Enables automatic redirection if the current route can't be matched but a
+	// handler for the path with (without) the trailing slash exists.
+	// For example if /foo/ is requested but a route only exists for /foo, the
+	// client is redirected to /foo with http status code 301 for GET requests
+	// and 307 for all other request methods.
+	RedirectTrailingSlash bool
+
+	// If enabled, the router tries to fix the current request path, if no
+	// handle is registered for it.
+	// First superfluous path elements like ../ or // are removed.
+	// Afterwards the router does a case-insensitive lookup of the cleaned path.
+	// If a handle can be found for this route, the router makes a redirection
+	// to the corrected path with status code 301 for GET requests and 307 for
+	// all other request methods.
+	// For example /FOO and /..//Foo could be redirected to /foo.
+	// RedirectTrailingSlash is independent of this option.
+	RedirectFixedPath bool
+
+	// If enabled, the router checks if another method is allowed for the
+	// current route, if the current request can not be routed.
+	// If this is the case, the request is answered with 'Method Not Allowed'
+	// and HTTP status code 405.
+	// If no other Method is allowed, the request is delegated to the NotFound
+	// handler.
+	HandleMethodNotAllowed bool
+
+	// If enabled, the router automatically replies to OPTIONS requests.
+	// Custom OPTIONS handlers take priority over automatic replies.
+	HandleOPTIONS bool
+
+	// An optional http.Handler that is called on automatic OPTIONS requests.
+	// The handler is only called if HandleOPTIONS is true and no OPTIONS
+	// handler for the specific path was set.
+	// The "Allowed" header is set before calling the handler.
+	GlobalOPTIONS http.Handler
+
+	// Cached value of global (*) allowed methods
+	globalAllowed string
+
+	// Configurable http.Handler which is called when no matching route is
+	// found. If it is not set, http.NotFound is used.
+	NotFound http.Handler
+
+	// Configurable http.Handler which is called when a request
+	// cannot be routed and HandleMethodNotAllowed is true.
+	// If it is not set, http.Error with http.StatusMethodNotAllowed is used.
+	// The "Allow" header with allowed request methods is set before the handler
+	// is called.
+	MethodNotAllowed http.Handler
+
+	// Function to handle panics recovered from http handlers.
+	// It should be used to generate a error page and return the http error code
+	// 500 (Internal Server Error).
+	// The handler can be used to keep your server from crashing because of
+	// unrecovered panics.
+	PanicHandler func(http.ResponseWriter, *http.Request, interface{})
+}
+
+// Make sure the Router conforms with the http.Handler interface
+var _ http.Handler = New()
+
+// New returns a new initialized Router.
+// Path auto-correction, including trailing slashes, is enabled by default.
+func New() *Router {
+	return &Router{
+		RedirectTrailingSlash:  true,
+		RedirectFixedPath:      true,
+		HandleMethodNotAllowed: true,
+		HandleOPTIONS:          true,
+	}
+}
+
+// GET is a shortcut for router.Handle(http.MethodGet, path, handle)
+func (r *Router) GET(path string, handle Handle) {
+	r.Handle(http.MethodGet, path, handle)
+}
+
+// HEAD is a shortcut for router.Handle(http.MethodHead, path, handle)
+func (r *Router) HEAD(path string, handle Handle) {
+	r.Handle(http.MethodHead, path, handle)
+}
+
+// OPTIONS is a shortcut for router.Handle(http.MethodOptions, path, handle)
+func (r *Router) OPTIONS(path string, handle Handle) {
+	r.Handle(http.MethodOptions, path, handle)
+}
+
+// POST is a shortcut for router.Handle(http.MethodPost, path, handle)
+func (r *Router) POST(path string, handle Handle) {
+	r.Handle(http.MethodPost, path, handle)
+}
+
+// PUT is a shortcut for router.Handle(http.MethodPut, path, handle)
+func (r *Router) PUT(path string, handle Handle) {
+	r.Handle(http.MethodPut, path, handle)
+}
+
+// PATCH is a shortcut for router.Handle(http.MethodPatch, path, handle)
+func (r *Router) PATCH(path string, handle Handle) {
+	r.Handle(http.MethodPatch, path, handle)
+}
+
+// DELETE is a shortcut for router.Handle(http.MethodDelete, path, handle)
+func (r *Router) DELETE(path string, handle Handle) {
+	r.Handle(http.MethodDelete, path, handle)
+}
+
+// Handle registers a new request handle with the given path and method.
+//
+// For GET, POST, PUT, PATCH and DELETE requests the respective shortcut
+// functions can be used.
+//
+// This function is intended for bulk loading and to allow the usage of less
+// frequently used, non-standardized or custom methods (e.g. for internal
+// communication with a proxy).
+func (r *Router) Handle(method, path string, handle Handle) {
+	if len(path) < 1 || path[0] != '/' {
+		panic("path must begin with '/' in path '" + path + "'")
+	}
+
+	if r.trees == nil {
+		r.trees = make(map[string]*node)
+	}
+
+	root := r.trees[method]
+	if root == nil {
+		root = new(node)
+		r.trees[method] = root
+
+		r.globalAllowed = r.allowed("*", "")
+	}
+
+	root.addRoute(path, handle)
+}
+
+// Handler is an adapter which allows the usage of an http.Handler as a
+// request handle.
+// The Params are available in the request context under ParamsKey.
+func (r *Router) Handler(method, path string, handler http.Handler) {
+	r.Handle(method, path,
+		func(w http.ResponseWriter, req *http.Request, p Params) {
+			if len(p) > 0 {
+				ctx := req.Context()
+				ctx = context.WithValue(ctx, ParamsKey, p)
+				req = req.WithContext(ctx)
+			}
+			handler.ServeHTTP(w, req)
+		},
+	)
+}
+
+// HandlerFunc is an adapter which allows the usage of an http.HandlerFunc as a
+// request handle.
+func (r *Router) HandlerFunc(method, path string, handler http.HandlerFunc) {
+	r.Handler(method, path, handler)
+}
+
+// ServeFiles serves files from the given file system root.
+// The path must end with "/*filepath", files are then served from the local
+// path /defined/root/dir/*filepath.
+// For example if root is "/etc" and *filepath is "passwd", the local file
+// "/etc/passwd" would be served.
+// Internally a http.FileServer is used, therefore http.NotFound is used instead
+// of the Router's NotFound handler.
+// To use the operating system's file system implementation,
+// use http.Dir:
+//     router.ServeFiles("/src/*filepath", http.Dir("/var/www"))
+func (r *Router) ServeFiles(path string, root http.FileSystem) {
+	if len(path) < 10 || path[len(path)-10:] != "/*filepath" {
+		panic("path must end with /*filepath in path '" + path + "'")
+	}
+
+	fileServer := http.FileServer(root)
+
+	r.GET(path, func(w http.ResponseWriter, req *http.Request, ps Params) {
+		req.URL.Path = ps.ByName("filepath")
+		fileServer.ServeHTTP(w, req)
+	})
+}
+
+func (r *Router) recv(w http.ResponseWriter, req *http.Request) {
+	if rcv := recover(); rcv != nil {
+		r.PanicHandler(w, req, rcv)
+	}
+}
+
+// Lookup allows the manual lookup of a method + path combo.
+// This is e.g. useful to build a framework around this router.
+// If the path was found, it returns the handle function and the path parameter
+// values. Otherwise the third return value indicates whether a redirection to
+// the same path with an extra / without the trailing slash should be performed.
+func (r *Router) Lookup(method, path string) (Handle, Params, bool) {
+	if root := r.trees[method]; root != nil {
+		return root.getValue(path)
+	}
+	return nil, nil, false
+}
+
+func (r *Router) allowed(path, reqMethod string) (allow string) {
+	allowed := make([]string, 0, 9)
+
+	if path == "*" { // server-wide
+		// empty method is used for internal calls to refresh the cache
+		if reqMethod == "" {
+			for method := range r.trees {
+				if method == http.MethodOptions {
+					continue
+				}
+				// Add request method to list of allowed methods
+				allowed = append(allowed, method)
+			}
+		} else {
+			return r.globalAllowed
+		}
+	} else { // specific path
+		for method := range r.trees {
+			// Skip the requested method - we already tried this one
+			if method == reqMethod || method == http.MethodOptions {
+				continue
+			}
+
+			handle, _, _ := r.trees[method].getValue(path)
+			if handle != nil {
+				// Add request method to list of allowed methods
+				allowed = append(allowed, method)
+			}
+		}
+	}
+
+	if len(allowed) > 0 {
+		// Add request method to list of allowed methods
+		allowed = append(allowed, http.MethodOptions)
+
+		// Sort allowed methods.
+		// sort.Strings(allowed) unfortunately causes unnecessary allocations
+		// due to allowed being moved to the heap and interface conversion
+		for i, l := 1, len(allowed); i < l; i++ {
+			for j := i; j > 0 && allowed[j] < allowed[j-1]; j-- {
+				allowed[j], allowed[j-1] = allowed[j-1], allowed[j]
+			}
+		}
+
+		// return as comma separated list
+		return strings.Join(allowed, ", ")
+	}
+	return
+}
+
+// ServeHTTP makes the router implement the http.Handler interface.
+func (r *Router) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	if r.PanicHandler != nil {
+		defer r.recv(w, req)
+	}
+
+	path := req.URL.Path
+
+	if root := r.trees[req.Method]; root != nil {
+		if handle, ps, tsr := root.getValue(path); handle != nil {
+			handle(w, req, ps)
+			return
+		} else if req.Method != http.MethodConnect && path != "/" {
+			code := 301 // Permanent redirect, request with GET method
+			if req.Method != http.MethodGet {
+				// Temporary redirect, request with same method
+				// As of Go 1.3, Go does not support status code 308.
+				code = 307
+			}
+
+			if tsr && r.RedirectTrailingSlash {
+				if len(path) > 1 && path[len(path)-1] == '/' {
+					req.URL.Path = path[:len(path)-1]
+				} else {
+					req.URL.Path = path + "/"
+				}
+				http.Redirect(w, req, req.URL.String(), code)
+				return
+			}
+
+			// Try to fix the request path
+			if r.RedirectFixedPath {
+				fixedPath, found := root.findCaseInsensitivePath(
+					CleanPath(path),
+					r.RedirectTrailingSlash,
+				)
+				if found {
+					req.URL.Path = string(fixedPath)
+					http.Redirect(w, req, req.URL.String(), code)
+					return
+				}
+			}
+		}
+	}
+
+	if req.Method == http.MethodOptions && r.HandleOPTIONS {
+		// Handle OPTIONS requests
+		if allow := r.allowed(path, http.MethodOptions); allow != "" {
+			w.Header().Set("Allow", allow)
+			if r.GlobalOPTIONS != nil {
+				r.GlobalOPTIONS.ServeHTTP(w, req)
+			}
+			return
+		}
+	} else if r.HandleMethodNotAllowed { // Handle 405
+		if allow := r.allowed(path, req.Method); allow != "" {
+			w.Header().Set("Allow", allow)
+			if r.MethodNotAllowed != nil {
+				r.MethodNotAllowed.ServeHTTP(w, req)
+			} else {
+				http.Error(w,
+					http.StatusText(http.StatusMethodNotAllowed),
+					http.StatusMethodNotAllowed,
+				)
+			}
+			return
+		}
+	}
+
+	// Handle 404
+	if r.NotFound != nil {
+		r.NotFound.ServeHTTP(w, req)
+	} else {
+		http.NotFound(w, req)
+	}
+}

vendor/github.com/julienschmidt/httprouter/tree.go

@@ -0,0 +1,666 @@
+// Copyright 2013 Julien Schmidt. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be found
+// in the LICENSE file.
+
+package httprouter
+
+import (
+	"strings"
+	"unicode"
+	"unicode/utf8"
+)
+
+func min(a, b int) int {
+	if a <= b {
+		return a
+	}
+	return b
+}
+
+const maxParamCount uint8 = ^uint8(0)
+
+func countParams(path string) uint8 {
+	var n uint
+	for i := 0; i < len(path); i++ {
+		if path[i] != ':' && path[i] != '*' {
+			continue
+		}
+		n++
+	}
+	if n >= uint(maxParamCount) {
+		return maxParamCount
+	}
+
+	return uint8(n)
+}
+
+type nodeType uint8
+
+const (
+	static nodeType = iota // default
+	root
+	param
+	catchAll
+)
+
+type node struct {
+	path      string
+	wildChild bool
+	nType     nodeType
+	maxParams uint8
+	priority  uint32
+	indices   string
+	children  []*node
+	handle    Handle
+}
+
+// increments priority of the given child and reorders if necessary
+func (n *node) incrementChildPrio(pos int) int {
+	n.children[pos].priority++
+	prio := n.children[pos].priority
+
+	// adjust position (move to front)
+	newPos := pos
+	for newPos > 0 && n.children[newPos-1].priority < prio {
+		// swap node positions
+		n.children[newPos-1], n.children[newPos] = n.children[newPos], n.children[newPos-1]
+
+		newPos--
+	}
+
+	// build new index char string
+	if newPos != pos {
+		n.indices = n.indices[:newPos] + // unchanged prefix, might be empty
+			n.indices[pos:pos+1] + // the index char we move
+			n.indices[newPos:pos] + n.indices[pos+1:] // rest without char at 'pos'
+	}
+
+	return newPos
+}
+
+// addRoute adds a node with the given handle to the path.
+// Not concurrency-safe!
+func (n *node) addRoute(path string, handle Handle) {
+	fullPath := path
+	n.priority++
+	numParams := countParams(path)
+
+	// non-empty tree
+	if len(n.path) > 0 || len(n.children) > 0 {
+	walk:
+		for {
+			// Update maxParams of the current node
+			if numParams > n.maxParams {
+				n.maxParams = numParams
+			}
+
+			// Find the longest common prefix.
+			// This also implies that the common prefix contains no ':' or '*'
+			// since the existing key can't contain those chars.
+			i := 0
+			max := min(len(path), len(n.path))
+			for i < max && path[i] == n.path[i] {
+				i++
+			}
+
+			// Split edge
+			if i < len(n.path) {
+				child := node{
+					path:      n.path[i:],
+					wildChild: n.wildChild,
+					nType:     static,
+					indices:   n.indices,
+					children:  n.children,
+					handle:    n.handle,
+					priority:  n.priority - 1,
+				}
+
+				// Update maxParams (max of all children)
+				for i := range child.children {
+					if child.children[i].maxParams > child.maxParams {
+						child.maxParams = child.children[i].maxParams
+					}
+				}
+
+				n.children = []*node{&child}
+				// []byte for proper unicode char conversion, see #65
+				n.indices = string([]byte{n.path[i]})
+				n.path = path[:i]
+				n.handle = nil
+				n.wildChild = false
+			}
+
+			// Make new node a child of this node
+			if i < len(path) {
+				path = path[i:]
+
+				if n.wildChild {
+					n = n.children[0]
+					n.priority++
+
+					// Update maxParams of the child node
+					if numParams > n.maxParams {
+						n.maxParams = numParams
+					}
+					numParams--
+
+					// Check if the wildcard matches
+					if len(path) >= len(n.path) && n.path == path[:len(n.path)] &&
+						// Adding a child to a catchAll is not possible
+						n.nType != catchAll &&
+						// Check for longer wildcard, e.g. :name and :names
+						(len(n.path) >= len(path) || path[len(n.path)] == '/') {
+						continue walk
+					} else {
+						// Wildcard conflict
+						var pathSeg string
+						if n.nType == catchAll {
+							pathSeg = path
+						} else {
+							pathSeg = strings.SplitN(path, "/", 2)[0]
+						}
+						prefix := fullPath[:strings.Index(fullPath, pathSeg)] + n.path
+						panic("'" + pathSeg +
+							"' in new path '" + fullPath +
+							"' conflicts with existing wildcard '" + n.path +
+							"' in existing prefix '" + prefix +
+							"'")
+					}
+				}
+
+				c := path[0]
+
+				// slash after param
+				if n.nType == param && c == '/' && len(n.children) == 1 {
+					n = n.children[0]
+					n.priority++
+					continue walk
+				}
+
+				// Check if a child with the next path byte exists
+				for i := 0; i < len(n.indices); i++ {
+					if c == n.indices[i] {
+						i = n.incrementChildPrio(i)
+						n = n.children[i]
+						continue walk
+					}
+				}
+
+				// Otherwise insert it
+				if c != ':' && c != '*' {
+					// []byte for proper unicode char conversion, see #65
+					n.indices += string([]byte{c})
+					child := &node{
+						maxParams: numParams,
+					}
+					n.children = append(n.children, child)
+					n.incrementChildPrio(len(n.indices) - 1)
+					n = child
+				}
+				n.insertChild(numParams, path, fullPath, handle)
+				return
+
+			} else if i == len(path) { // Make node a (in-path) leaf
+				if n.handle != nil {
+					panic("a handle is already registered for path '" + fullPath + "'")
+				}
+				n.handle = handle
+			}
+			return
+		}
+	} else { // Empty tree
+		n.insertChild(numParams, path, fullPath, handle)
+		n.nType = root
+	}
+}
+
+func (n *node) insertChild(numParams uint8, path, fullPath string, handle Handle) {
+	var offset int // already handled bytes of the path
+
+	// find prefix until first wildcard (beginning with ':'' or '*'')
+	for i, max := 0, len(path); numParams > 0; i++ {
+		c := path[i]
+		if c != ':' && c != '*' {
+			continue
+		}
+
+		// find wildcard end (either '/' or path end)
+		end := i + 1
+		for end < max && path[end] != '/' {
+			switch path[end] {
+			// the wildcard name must not contain ':' and '*'
+			case ':', '*':
+				panic("only one wildcard per path segment is allowed, has: '" +
+					path[i:] + "' in path '" + fullPath + "'")
+			default:
+				end++
+			}
+		}
+
+		// check if this Node existing children which would be
+		// unreachable if we insert the wildcard here
+		if len(n.children) > 0 {
+			panic("wildcard route '" + path[i:end] +
+				"' conflicts with existing children in path '" + fullPath + "'")
+		}
+
+		// check if the wildcard has a name
+		if end-i < 2 {
+			panic("wildcards must be named with a non-empty name in path '" + fullPath + "'")
+		}
+
+		if c == ':' { // param
+			// split path at the beginning of the wildcard
+			if i > 0 {
+				n.path = path[offset:i]
+				offset = i
+			}
+
+			child := &node{
+				nType:     param,
+				maxParams: numParams,
+			}
+			n.children = []*node{child}
+			n.wildChild = true
+			n = child
+			n.priority++
+			numParams--
+
+			// if the path doesn't end with the wildcard, then there
+			// will be another non-wildcard subpath starting with '/'
+			if end < max {
+				n.path = path[offset:end]
+				offset = end
+
+				child := &node{
+					maxParams: numParams,
+					priority:  1,
+				}
+				n.children = []*node{child}
+				n = child
+			}
+
+		} else { // catchAll
+			if end != max || numParams > 1 {
+				panic("catch-all routes are only allowed at the end of the path in path '" + fullPath + "'")
+			}
+
+			if len(n.path) > 0 && n.path[len(n.path)-1] == '/' {
+				panic("catch-all conflicts with existing handle for the path segment root in path '" + fullPath + "'")
+			}
+
+			// currently fixed width 1 for '/'
+			i--
+			if path[i] != '/' {
+				panic("no / before catch-all in path '" + fullPath + "'")
+			}
+
+			n.path = path[offset:i]
+
+			// first node: catchAll node with empty path
+			child := &node{
+				wildChild: true,
+				nType:     catchAll,
+				maxParams: 1,
+			}
+			// update maxParams of the parent node
+			if n.maxParams < 1 {
+				n.maxParams = 1
+			}
+			n.children = []*node{child}
+			n.indices = string(path[i])
+			n = child
+			n.priority++
+
+			// second node: node holding the variable
+			child = &node{
+				path:      path[i:],
+				nType:     catchAll,
+				maxParams: 1,
+				handle:    handle,
+				priority:  1,
+			}
+			n.children = []*node{child}
+
+			return
+		}
+	}
+
+	// insert remaining path part and handle to the leaf
+	n.path = path[offset:]
+	n.handle = handle
+}
+
+// Returns the handle registered with the given path (key). The values of
+// wildcards are saved to a map.
+// If no handle can be found, a TSR (trailing slash redirect) recommendation is
+// made if a handle exists with an extra (without the) trailing slash for the
+// given path.
+func (n *node) getValue(path string) (handle Handle, p Params, tsr bool) {
+walk: // outer loop for walking the tree
+	for {
+		if len(path) > len(n.path) {
+			if path[:len(n.path)] == n.path {
+				path = path[len(n.path):]
+				// If this node does not have a wildcard (param or catchAll)
+				// child,  we can just look up the next child node and continue
+				// to walk down the tree
+				if !n.wildChild {
+					c := path[0]
+					for i := 0; i < len(n.indices); i++ {
+						if c == n.indices[i] {
+							n = n.children[i]
+							continue walk
+						}
+					}
+
+					// Nothing found.
+					// We can recommend to redirect to the same URL without a
+					// trailing slash if a leaf exists for that path.
+					tsr = (path == "/" && n.handle != nil)
+					return
+
+				}
+
+				// handle wildcard child
+				n = n.children[0]
+				switch n.nType {
+				case param:
+					// find param end (either '/' or path end)
+					end := 0
+					for end < len(path) && path[end] != '/' {
+						end++
+					}
+
+					// save param value
+					if p == nil {
+						// lazy allocation
+						p = make(Params, 0, n.maxParams)
+					}
+					i := len(p)
+					p = p[:i+1] // expand slice within preallocated capacity
+					p[i].Key = n.path[1:]
+					p[i].Value = path[:end]
+
+					// we need to go deeper!
+					if end < len(path) {
+						if len(n.children) > 0 {
+							path = path[end:]
+							n = n.children[0]
+							continue walk
+						}
+
+						// ... but we can't
+						tsr = (len(path) == end+1)
+						return
+					}
+
+					if handle = n.handle; handle != nil {
+						return
+					} else if len(n.children) == 1 {
+						// No handle found. Check if a handle for this path + a
+						// trailing slash exists for TSR recommendation
+						n = n.children[0]
+						tsr = (n.path == "/" && n.handle != nil)
+					}
+
+					return
+
+				case catchAll:
+					// save param value
+					if p == nil {
+						// lazy allocation
+						p = make(Params, 0, n.maxParams)
+					}
+					i := len(p)
+					p = p[:i+1] // expand slice within preallocated capacity
+					p[i].Key = n.path[2:]
+					p[i].Value = path
+
+					handle = n.handle
+					return
+
+				default:
+					panic("invalid node type")
+				}
+			}
+		} else if path == n.path {
+			// We should have reached the node containing the handle.
+			// Check if this node has a handle registered.
+			if handle = n.handle; handle != nil {
+				return
+			}
+
+			if path == "/" && n.wildChild && n.nType != root {
+				tsr = true
+				return
+			}
+
+			// No handle found. Check if a handle for this path + a
+			// trailing slash exists for trailing slash recommendation
+			for i := 0; i < len(n.indices); i++ {
+				if n.indices[i] == '/' {
+					n = n.children[i]
+					tsr = (len(n.path) == 1 && n.handle != nil) ||
+						(n.nType == catchAll && n.children[0].handle != nil)
+					return
+				}
+			}
+
+			return
+		}
+
+		// Nothing found. We can recommend to redirect to the same URL with an
+		// extra trailing slash if a leaf exists for that path
+		tsr = (path == "/") ||
+			(len(n.path) == len(path)+1 && n.path[len(path)] == '/' &&
+				path == n.path[:len(n.path)-1] && n.handle != nil)
+		return
+	}
+}
+
+// Makes a case-insensitive lookup of the given path and tries to find a handler.
+// It can optionally also fix trailing slashes.
+// It returns the case-corrected path and a bool indicating whether the lookup
+// was successful.
+func (n *node) findCaseInsensitivePath(path string, fixTrailingSlash bool) (ciPath []byte, found bool) {
+	return n.findCaseInsensitivePathRec(
+		path,
+		make([]byte, 0, len(path)+1), // preallocate enough memory for new path
+		[4]byte{},                    // empty rune buffer
+		fixTrailingSlash,
+	)
+}
+
+// shift bytes in array by n bytes left
+func shiftNRuneBytes(rb [4]byte, n int) [4]byte {
+	switch n {
+	case 0:
+		return rb
+	case 1:
+		return [4]byte{rb[1], rb[2], rb[3], 0}
+	case 2:
+		return [4]byte{rb[2], rb[3]}
+	case 3:
+		return [4]byte{rb[3]}
+	default:
+		return [4]byte{}
+	}
+}
+
+// recursive case-insensitive lookup function used by n.findCaseInsensitivePath
+func (n *node) findCaseInsensitivePathRec(path string, ciPath []byte, rb [4]byte, fixTrailingSlash bool) ([]byte, bool) {
+	npLen := len(n.path)
+
+walk: // outer loop for walking the tree
+	for len(path) >= npLen && (npLen == 0 || strings.EqualFold(path[1:npLen], n.path[1:])) {
+		// add common prefix to result
+
+		oldPath := path
+		path = path[npLen:]
+		ciPath = append(ciPath, n.path...)
+
+		if len(path) > 0 {
+			// If this node does not have a wildcard (param or catchAll) child,
+			// we can just look up the next child node and continue to walk down
+			// the tree
+			if !n.wildChild {
+				// skip rune bytes already processed
+				rb = shiftNRuneBytes(rb, npLen)
+
+				if rb[0] != 0 {
+					// old rune not finished
+					for i := 0; i < len(n.indices); i++ {
+						if n.indices[i] == rb[0] {
+							// continue with child node
+							n = n.children[i]
+							npLen = len(n.path)
+							continue walk
+						}
+					}
+				} else {
+					// process a new rune
+					var rv rune
+
+					// find rune start
+					// runes are up to 4 byte long,
+					// -4 would definitely be another rune
+					var off int
+					for max := min(npLen, 3); off < max; off++ {
+						if i := npLen - off; utf8.RuneStart(oldPath[i]) {
+							// read rune from cached path
+							rv, _ = utf8.DecodeRuneInString(oldPath[i:])
+							break
+						}
+					}
+
+					// calculate lowercase bytes of current rune
+					lo := unicode.ToLower(rv)
+					utf8.EncodeRune(rb[:], lo)
+
+					// skip already processed bytes
+					rb = shiftNRuneBytes(rb, off)
+
+					for i := 0; i < len(n.indices); i++ {
+						// lowercase matches
+						if n.indices[i] == rb[0] {
+							// must use a recursive approach since both the
+							// uppercase byte and the lowercase byte might exist
+							// as an index
+							if out, found := n.children[i].findCaseInsensitivePathRec(
+								path, ciPath, rb, fixTrailingSlash,
+							); found {
+								return out, true
+							}
+							break
+						}
+					}
+
+					// if we found no match, the same for the uppercase rune,
+					// if it differs
+					if up := unicode.ToUpper(rv); up != lo {
+						utf8.EncodeRune(rb[:], up)
+						rb = shiftNRuneBytes(rb, off)
+
+						for i, c := 0, rb[0]; i < len(n.indices); i++ {
+							// uppercase matches
+							if n.indices[i] == c {
+								// continue with child node
+								n = n.children[i]
+								npLen = len(n.path)
+								continue walk
+							}
+						}
+					}
+				}
+
+				// Nothing found. We can recommend to redirect to the same URL
+				// without a trailing slash if a leaf exists for that path
+				return ciPath, (fixTrailingSlash && path == "/" && n.handle != nil)
+			}
+
+			n = n.children[0]
+			switch n.nType {
+			case param:
+				// find param end (either '/' or path end)
+				k := 0
+				for k < len(path) && path[k] != '/' {
+					k++
+				}
+
+				// add param value to case insensitive path
+				ciPath = append(ciPath, path[:k]...)
+
+				// we need to go deeper!
+				if k < len(path) {
+					if len(n.children) > 0 {
+						// continue with child node
+						n = n.children[0]
+						npLen = len(n.path)
+						path = path[k:]
+						continue
+					}
+
+					// ... but we can't
+					if fixTrailingSlash && len(path) == k+1 {
+						return ciPath, true
+					}
+					return ciPath, false
+				}
+
+				if n.handle != nil {
+					return ciPath, true
+				} else if fixTrailingSlash && len(n.children) == 1 {
+					// No handle found. Check if a handle for this path + a
+					// trailing slash exists
+					n = n.children[0]
+					if n.path == "/" && n.handle != nil {
+						return append(ciPath, '/'), true
+					}
+				}
+				return ciPath, false
+
+			case catchAll:
+				return append(ciPath, path...), true
+
+			default:
+				panic("invalid node type")
+			}
+		} else {
+			// We should have reached the node containing the handle.
+			// Check if this node has a handle registered.
+			if n.handle != nil {
+				return ciPath, true
+			}
+
+			// No handle found.
+			// Try to fix the path by adding a trailing slash
+			if fixTrailingSlash {
+				for i := 0; i < len(n.indices); i++ {
+					if n.indices[i] == '/' {
+						n = n.children[i]
+						if (len(n.path) == 1 && n.handle != nil) ||
+							(n.nType == catchAll && n.children[0].handle != nil) {
+							return append(ciPath, '/'), true
+						}
+						return ciPath, false
+					}
+				}
+			}
+			return ciPath, false
+		}
+	}
+
+	// Nothing found.
+	// Try to fix the path by adding / removing a trailing slash
+	if fixTrailingSlash {
+		if path == "/" {
+			return ciPath, true
+		}
+		if len(path)+1 == npLen && n.path[len(path)] == '/' &&
+			strings.EqualFold(path[1:], n.path[1:len(path)]) && n.handle != nil {
+			return append(ciPath, n.path...), true
+		}
+	}
+	return ciPath, false
+}

vendor/github.com/mattn/go-sqlite3/.codecov.yml

@@ -0,0 +1,4 @@
+coverage:
+  status:
+    project: off
+    patch: off

vendor/github.com/mattn/go-sqlite3/.gitignore

@@ -0,0 +1,14 @@
+*.db
+*.exe
+*.dll
+*.o
+
+# VSCode
+.vscode
+
+# Exclude from upgrade
+upgrade/*.c
+upgrade/*.h
+
+# Exclude upgrade binary
+upgrade/upgrade

vendor/github.com/mattn/go-sqlite3/LICENSE

@@ -0,0 +1,21 @@
+The MIT License (MIT)
+
+Copyright (c) 2014 Yasuhiro Matsumoto
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

vendor/github.com/mattn/go-sqlite3/README.md

@@ -0,0 +1,593 @@
+go-sqlite3
+==========
+
+[![Go Reference](https://pkg.go.dev/badge/github.com/mattn/go-sqlite3.svg)](https://pkg.go.dev/github.com/mattn/go-sqlite3)
+[![GitHub Actions](https://github.com/mattn/go-sqlite3/workflows/Go/badge.svg)](https://github.com/mattn/go-sqlite3/actions?query=workflow%3AGo)
+[![Financial Contributors on Open Collective](https://opencollective.com/mattn-go-sqlite3/all/badge.svg?label=financial+contributors)](https://opencollective.com/mattn-go-sqlite3) 
+[![codecov](https://codecov.io/gh/mattn/go-sqlite3/branch/master/graph/badge.svg)](https://codecov.io/gh/mattn/go-sqlite3)
+[![Go Report Card](https://goreportcard.com/badge/github.com/mattn/go-sqlite3)](https://goreportcard.com/report/github.com/mattn/go-sqlite3)
+
+Latest stable version is v1.14 or later, not v2.
+
+~~**NOTE:** The increase to v2 was an accident. There were no major changes or features.~~
+
+# Description
+
+A sqlite3 driver that conforms to the built-in database/sql interface.
+
+Supported Golang version: See [.github/workflows/go.yaml](./.github/workflows/go.yaml).
+
+This package follows the official [Golang Release Policy](https://golang.org/doc/devel/release.html#policy).
+
+### Overview
+
+- [go-sqlite3](#go-sqlite3)
+- [Description](#description)
+    - [Overview](#overview)
+- [Installation](#installation)
+- [API Reference](#api-reference)
+- [Connection String](#connection-string)
+  - [DSN Examples](#dsn-examples)
+- [Features](#features)
+    - [Usage](#usage)
+    - [Feature / Extension List](#feature--extension-list)
+- [Compilation](#compilation)
+  - [Android](#android)
+- [ARM](#arm)
+- [Cross Compile](#cross-compile)
+- [Google Cloud Platform](#google-cloud-platform)
+  - [Linux](#linux)
+    - [Alpine](#alpine)
+    - [Fedora](#fedora)
+    - [Ubuntu](#ubuntu)
+  - [Mac OSX](#mac-osx)
+  - [Windows](#windows)
+  - [Errors](#errors)
+- [User Authentication](#user-authentication)
+  - [Compile](#compile)
+  - [Usage](#usage-1)
+    - [Create protected database](#create-protected-database)
+    - [Password Encoding](#password-encoding)
+      - [Available Encoders](#available-encoders)
+    - [Restrictions](#restrictions)
+    - [Support](#support)
+    - [User Management](#user-management)
+      - [SQL](#sql)
+        - [Examples](#examples)
+      - [*SQLiteConn](#sqliteconn)
+    - [Attached database](#attached-database)
+- [Extensions](#extensions)
+  - [Spatialite](#spatialite)
+- [FAQ](#faq)
+- [License](#license)
+- [Author](#author)
+
+# Installation
+
+This package can be installed with the `go get` command:
+
+    go get github.com/mattn/go-sqlite3
+
+_go-sqlite3_ is *cgo* package.
+If you want to build your app using go-sqlite3, you need gcc.
+However, after you have built and installed _go-sqlite3_ with `go install github.com/mattn/go-sqlite3` (which requires gcc), you can build your app without relying on gcc in future.
+
+***Important: because this is a `CGO` enabled package, you are required to set the environment variable `CGO_ENABLED=1` and have a `gcc` compile present within your path.***
+
+# API Reference
+
+API documentation can be found [here](http://godoc.org/github.com/mattn/go-sqlite3).
+
+Examples can be found under the [examples](./_example) directory.
+
+# Connection String
+
+When creating a new SQLite database or connection to an existing one, with the file name additional options can be given.
+This is also known as a DSN (Data Source Name) string.
+
+Options are append after the filename of the SQLite database.
+The database filename and options are separated by an `?` (Question Mark).
+Options should be URL-encoded (see [url.QueryEscape](https://golang.org/pkg/net/url/#QueryEscape)).
+
+This also applies when using an in-memory database instead of a file.
+
+Options can be given using the following format: `KEYWORD=VALUE` and multiple options can be combined with the `&` ampersand.
+
+This library supports DSN options of SQLite itself and provides additional options.
+
+Boolean values can be one of:
+* `0` `no` `false` `off`
+* `1` `yes` `true` `on`
+
+| Name | Key | Value(s) | Description |
+|------|-----|----------|-------------|
+| UA - Create | `_auth` | - | Create User Authentication, for more information see [User Authentication](#user-authentication) |
+| UA - Username | `_auth_user` | `string` | Username for User Authentication, for more information see [User Authentication](#user-authentication) |
+| UA - Password | `_auth_pass` | `string` | Password for User Authentication, for more information see [User Authentication](#user-authentication) |
+| UA - Crypt | `_auth_crypt` | <ul><li>SHA1</li><li>SSHA1</li><li>SHA256</li><li>SSHA256</li><li>SHA384</li><li>SSHA384</li><li>SHA512</li><li>SSHA512</li></ul> | Password encoder to use for User Authentication, for more information see [User Authentication](#user-authentication) |
+| UA - Salt | `_auth_salt` | `string` | Salt to use if the configure password encoder requires a salt, for User Authentication, for more information see [User Authentication](#user-authentication) |
+| Auto Vacuum | `_auto_vacuum` \| `_vacuum` | <ul><li>`0` \| `none`</li><li>`1` \| `full`</li><li>`2` \| `incremental`</li></ul> | For more information see [PRAGMA auto_vacuum](https://www.sqlite.org/pragma.html#pragma_auto_vacuum) |
+| Busy Timeout | `_busy_timeout` \| `_timeout` | `int` | Specify value for sqlite3_busy_timeout. For more information see [PRAGMA busy_timeout](https://www.sqlite.org/pragma.html#pragma_busy_timeout) |
+| Case Sensitive LIKE | `_case_sensitive_like` \| `_cslike` | `boolean` | For more information see [PRAGMA case_sensitive_like](https://www.sqlite.org/pragma.html#pragma_case_sensitive_like) |
+| Defer Foreign Keys | `_defer_foreign_keys` \| `_defer_fk` | `boolean` | For more information see [PRAGMA defer_foreign_keys](https://www.sqlite.org/pragma.html#pragma_defer_foreign_keys) |
+| Foreign Keys | `_foreign_keys` \| `_fk` | `boolean` | For more information see [PRAGMA foreign_keys](https://www.sqlite.org/pragma.html#pragma_foreign_keys) |
+| Ignore CHECK Constraints | `_ignore_check_constraints` | `boolean` | For more information see [PRAGMA ignore_check_constraints](https://www.sqlite.org/pragma.html#pragma_ignore_check_constraints) |
+| Immutable | `immutable` | `boolean` | For more information see [Immutable](https://www.sqlite.org/c3ref/open.html) |
+| Journal Mode | `_journal_mode` \| `_journal` | <ul><li>DELETE</li><li>TRUNCATE</li><li>PERSIST</li><li>MEMORY</li><li>WAL</li><li>OFF</li></ul> | For more information see [PRAGMA journal_mode](https://www.sqlite.org/pragma.html#pragma_journal_mode) |
+| Locking Mode | `_locking_mode` \| `_locking` | <ul><li>NORMAL</li><li>EXCLUSIVE</li></ul> | For more information see [PRAGMA locking_mode](https://www.sqlite.org/pragma.html#pragma_locking_mode) |
+| Mode | `mode` | <ul><li>ro</li><li>rw</li><li>rwc</li><li>memory</li></ul> | Access Mode of the database. For more information see [SQLite Open](https://www.sqlite.org/c3ref/open.html) |
+| Mutex Locking | `_mutex` | <ul><li>no</li><li>full</li></ul> | Specify mutex mode. |
+| Query Only | `_query_only` | `boolean` | For more information see [PRAGMA query_only](https://www.sqlite.org/pragma.html#pragma_query_only) |
+| Recursive Triggers | `_recursive_triggers` \| `_rt` | `boolean` | For more information see [PRAGMA recursive_triggers](https://www.sqlite.org/pragma.html#pragma_recursive_triggers) |
+| Secure Delete | `_secure_delete` | `boolean` \| `FAST` | For more information see [PRAGMA secure_delete](https://www.sqlite.org/pragma.html#pragma_secure_delete) |
+| Shared-Cache Mode | `cache` | <ul><li>shared</li><li>private</li></ul> | Set cache mode for more information see [sqlite.org](https://www.sqlite.org/sharedcache.html) |
+| Synchronous | `_synchronous` \| `_sync` | <ul><li>0 \| OFF</li><li>1 \| NORMAL</li><li>2 \| FULL</li><li>3 \| EXTRA</li></ul> | For more information see [PRAGMA synchronous](https://www.sqlite.org/pragma.html#pragma_synchronous) |
+| Time Zone Location | `_loc` | auto | Specify location of time format. |
+| Transaction Lock | `_txlock` | <ul><li>immediate</li><li>deferred</li><li>exclusive</li></ul> | Specify locking behavior for transactions. |
+| Writable Schema | `_writable_schema` | `Boolean` | When this pragma is on, the SQLITE_MASTER tables in which database can be changed using ordinary UPDATE, INSERT, and DELETE statements. Warning: misuse of this pragma can easily result in a corrupt database file. |
+| Cache Size | `_cache_size` | `int` | Maximum cache size; default is 2000K (2M). See [PRAGMA cache_size](https://sqlite.org/pragma.html#pragma_cache_size) |
+
+
+## DSN Examples
+
+```
+file:test.db?cache=shared&mode=memory
+```
+
+# Features
+
+This package allows additional configuration of features available within SQLite3 to be enabled or disabled by golang build constraints also known as build `tags`.
+
+Click [here](https://golang.org/pkg/go/build/#hdr-Build_Constraints) for more information about build tags / constraints.
+
+### Usage
+
+If you wish to build this library with additional extensions / features, use the following command:
+
+```bash
+go build --tags "<FEATURE>"
+```
+
+For available features, see the extension list.
+When using multiple build tags, all the different tags should be space delimited.
+
+Example:
+
+```bash
+go build --tags "icu json1 fts5 secure_delete"
+```
+
+### Feature / Extension List
+
+| Extension | Build Tag | Description |
+|-----------|-----------|-------------|
+| Additional Statistics | sqlite_stat4 | This option adds additional logic to the ANALYZE command and to the query planner that can help SQLite to chose a better query plan under certain situations. The ANALYZE command is enhanced to collect histogram data from all columns of every index and store that data in the sqlite_stat4 table.<br><br>The query planner will then use the histogram data to help it make better index choices. The downside of this compile-time option is that it violates the query planner stability guarantee making it more difficult to ensure consistent performance in mass-produced applications.<br><br>SQLITE_ENABLE_STAT4 is an enhancement of SQLITE_ENABLE_STAT3. STAT3 only recorded histogram data for the left-most column of each index whereas the STAT4 enhancement records histogram data from all columns of each index.<br><br>The SQLITE_ENABLE_STAT3 compile-time option is a no-op and is ignored if the SQLITE_ENABLE_STAT4 compile-time option is used |
+| Allow URI Authority | sqlite_allow_uri_authority | URI filenames normally throws an error if the authority section is not either empty or "localhost".<br><br>However, if SQLite is compiled with the SQLITE_ALLOW_URI_AUTHORITY compile-time option, then the URI is converted into a Uniform Naming Convention (UNC) filename and passed down to the underlying operating system that way |
+| App Armor | sqlite_app_armor | When defined, this C-preprocessor macro activates extra code that attempts to detect misuse of the SQLite API, such as passing in NULL pointers to required parameters or using objects after they have been destroyed. <br><br>App Armor is not available under `Windows`. |
+| Disable Load Extensions | sqlite_omit_load_extension | Loading of external extensions is enabled by default.<br><br>To disable extension loading add the build tag `sqlite_omit_load_extension`. |
+| Foreign Keys | sqlite_foreign_keys | This macro determines whether enforcement of foreign key constraints is enabled or disabled by default for new database connections.<br><br>Each database connection can always turn enforcement of foreign key constraints on and off and run-time using the foreign_keys pragma.<br><br>Enforcement of foreign key constraints is normally off by default, but if this compile-time parameter is set to 1, enforcement of foreign key constraints will be on by default | 
+| Full Auto Vacuum | sqlite_vacuum_full | Set the default auto vacuum to full |
+| Incremental Auto Vacuum | sqlite_vacuum_incr | Set the default auto vacuum to incremental |
+| Full Text Search Engine | sqlite_fts5 | When this option is defined in the amalgamation, versions 5 of the full-text search engine (fts5) is added to the build automatically |
+|  International Components for Unicode | sqlite_icu | This option causes the International Components for Unicode or "ICU" extension to SQLite to be added to the build |
+| Introspect PRAGMAS | sqlite_introspect | This option adds some extra PRAGMA statements. <ul><li>PRAGMA function_list</li><li>PRAGMA module_list</li><li>PRAGMA pragma_list</li></ul> |
+| JSON SQL Functions | sqlite_json | When this option is defined in the amalgamation, the JSON SQL functions are added to the build automatically |
+| Math Functions | sqlite_math_functions | This compile-time option enables built-in scalar math functions. For more information see [Built-In Mathematical SQL Functions](https://www.sqlite.org/lang_mathfunc.html) |
+| OS Trace | sqlite_os_trace | This option enables OSTRACE() debug logging. This can be verbose and should not be used in production. |
+| Pre Update Hook | sqlite_preupdate_hook | Registers a callback function that is invoked prior to each INSERT, UPDATE, and DELETE operation on a database table. |
+| Secure Delete | sqlite_secure_delete | This compile-time option changes the default setting of the secure_delete pragma.<br><br>When this option is not used, secure_delete defaults to off. When this option is present, secure_delete defaults to on.<br><br>The secure_delete setting causes deleted content to be overwritten with zeros. There is a small performance penalty since additional I/O must occur.<br><br>On the other hand, secure_delete can prevent fragments of sensitive information from lingering in unused parts of the database file after it has been deleted. See the documentation on the secure_delete pragma for additional information |
+| Secure Delete (FAST) | sqlite_secure_delete_fast | For more information see [PRAGMA secure_delete](https://www.sqlite.org/pragma.html#pragma_secure_delete) |
+| Tracing / Debug | sqlite_trace | Activate trace functions |
+| User Authentication | sqlite_userauth | SQLite User Authentication see [User Authentication](#user-authentication) for more information. |
+| Virtual Tables | sqlite_vtable | SQLite Virtual Tables see [SQLite Official VTABLE Documentation](https://www.sqlite.org/vtab.html) for more information, and a [full example here](https://github.com/mattn/go-sqlite3/tree/master/_example/vtable) |
+
+# Compilation
+
+This package requires the `CGO_ENABLED=1` environment variable if not set by default, and the presence of the `gcc` compiler.
+
+If you need to add additional CFLAGS or LDFLAGS to the build command, and do not want to modify this package, then this can be achieved by using the `CGO_CFLAGS` and `CGO_LDFLAGS` environment variables.
+
+## Android
+
+This package can be compiled for android.
+Compile with:
+
+```bash
+go build --tags "android"
+```
+
+For more information see [#201](https://github.com/mattn/go-sqlite3/issues/201)
+
+# ARM
+
+To compile for `ARM` use the following environment:
+
+```bash
+env CC=arm-linux-gnueabihf-gcc CXX=arm-linux-gnueabihf-g++ \
+    CGO_ENABLED=1 GOOS=linux GOARCH=arm GOARM=7 \
+    go build -v 
+```
+
+Additional information:
+- [#242](https://github.com/mattn/go-sqlite3/issues/242)
+- [#504](https://github.com/mattn/go-sqlite3/issues/504)
+
+# Cross Compile
+
+This library can be cross-compiled.
+
+In some cases you are required to the `CC` environment variable with the cross compiler.
+
+## Cross Compiling from MAC OSX
+The simplest way to cross compile from OSX is to use [musl-cross](https://github.com/FiloSottile/homebrew-musl-cross).
+
+Steps:
+- Install [musl-cross](https://github.com/FiloSottile/homebrew-musl-cross) (`brew install FiloSottile/musl-cross/musl-cross`).
+- Run `CC=x86_64-linux-musl-gcc CXX=x86_64-linux-musl-g++ GOARCH=amd64 GOOS=linux CGO_ENABLED=1 go build -ldflags "-linkmode external -extldflags -static"`.
+
+Please refer to the project's [README](https://github.com/FiloSottile/homebrew-musl-cross#readme) for further information.
+
+# Google Cloud Platform
+
+Building on GCP is not possible because Google Cloud Platform does not allow `gcc` to be executed.
+
+Please work only with compiled final binaries.
+
+## Linux
+
+To compile this package on Linux, you must install the development tools for your linux distribution.
+
+To compile under linux use the build tag `linux`.
+
+```bash
+go build --tags "linux"
+```
+
+If you wish to link directly to libsqlite3 then you can use the `libsqlite3` build tag.
+
+```
+go build --tags "libsqlite3 linux"
+```
+
+### Alpine
+
+When building in an `alpine` container  run the following command before building:
+
+```
+apk add --update gcc musl-dev
+```
+
+### Fedora
+
+```bash
+sudo yum groupinstall "Development Tools" "Development Libraries"
+```
+
+### Ubuntu
+
+```bash
+sudo apt-get install build-essential
+```
+
+## Mac OSX
+
+OSX should have all the tools present to compile this package. If not, install XCode to add all the developers tools.
+
+Required dependency:
+
+```bash
+brew install sqlite3
+```
+
+For OSX, there is an additional package to install which is required if you wish to build the `icu` extension.
+
+This additional package can be installed with `homebrew`:
+
+```bash
+brew upgrade icu4c
+```
+
+To compile for Mac OSX:
+
+```bash
+go build --tags "darwin"
+```
+
+If you wish to link directly to libsqlite3, use the `libsqlite3` build tag:
+
+```
+go build --tags "libsqlite3 darwin"
+```
+
+Additional information:
+- [#206](https://github.com/mattn/go-sqlite3/issues/206)
+- [#404](https://github.com/mattn/go-sqlite3/issues/404)
+
+## Windows
+
+To compile this package on Windows, you must have the `gcc` compiler installed.
+
+1) Install a Windows `gcc` toolchain.
+2) Add the `bin` folder to the Windows path, if the installer did not do this by default.
+3) Open a terminal for the TDM-GCC toolchain, which can be found in the Windows Start menu.
+4) Navigate to your project folder and run the `go build ...` command for this package.
+
+For example the TDM-GCC Toolchain can be found [here](https://jmeubank.github.io/tdm-gcc/).
+
+## Errors
+
+- Compile error: `can not be used when making a shared object; recompile with -fPIC`
+
+    When receiving a compile time error referencing recompile with `-FPIC` then you
+    are probably using a hardend system.
+
+    You can compile the library on a hardend system with the following command.
+
+    ```bash
+    go build -ldflags '-extldflags=-fno-PIC'
+    ```
+
+    More details see [#120](https://github.com/mattn/go-sqlite3/issues/120)
+
+- Can't build go-sqlite3 on windows 64bit.
+
+    > Probably, you are using go 1.0, go1.0 has a problem when it comes to compiling/linking on windows 64bit.
+    > See: [#27](https://github.com/mattn/go-sqlite3/issues/27)
+
+- `go get github.com/mattn/go-sqlite3` throws compilation error.
+
+    `gcc` throws: `internal compiler error`
+
+    Remove the download repository from your disk and try re-install with:
+
+    ```bash
+    go install github.com/mattn/go-sqlite3
+    ```
+
+# User Authentication
+
+This package supports the SQLite User Authentication module.
+
+## Compile
+
+To use the User authentication module, the package has to be compiled with the tag `sqlite_userauth`. See [Features](#features).
+
+## Usage
+
+### Create protected database
+
+To create a database protected by user authentication, provide the following argument to the connection string `_auth`.
+This will enable user authentication within the database. This option however requires two additional arguments:
+
+- `_auth_user`
+- `_auth_pass`
+
+When `_auth` is present in the connection string user authentication will be enabled and the provided user will be created
+as an `admin` user. After initial creation, the parameter `_auth` has no effect anymore and can be omitted from the connection string.
+
+Example connection strings:
+
+Create an user authentication database with user `admin` and password `admin`:
+
+`file:test.s3db?_auth&_auth_user=admin&_auth_pass=admin`
+
+Create an user authentication database with user `admin` and password `admin` and use `SHA1` for the password encoding:
+
+`file:test.s3db?_auth&_auth_user=admin&_auth_pass=admin&_auth_crypt=sha1`
+
+### Password Encoding
+
+The passwords within the user authentication module of SQLite are encoded with the SQLite function `sqlite_cryp`.
+This function uses a ceasar-cypher which is quite insecure.
+This library provides several additional password encoders which can be configured through the connection string.
+
+The password cypher can be configured with the key `_auth_crypt`. And if the configured password encoder also requires an
+salt this can be configured with `_auth_salt`.
+
+#### Available Encoders
+
+- SHA1
+- SSHA1 (Salted SHA1)
+- SHA256
+- SSHA256 (salted SHA256)
+- SHA384
+- SSHA384 (salted SHA384)
+- SHA512
+- SSHA512 (salted SHA512)
+
+### Restrictions
+
+Operations on the database regarding user management can only be preformed by an administrator user.
+
+### Support
+
+The user authentication supports two kinds of users:
+
+- administrators
+- regular users
+
+### User Management
+
+User management can be done by directly using the `*SQLiteConn` or by SQL.
+
+#### SQL
+
+The following sql functions are available for user management:
+
+| Function | Arguments | Description |
+|----------|-----------|-------------|
+| `authenticate` | username `string`, password `string` | Will authenticate an user, this is done by the connection; and should not be used manually. |
+| `auth_user_add` | username `string`, password `string`, admin `int` | This function will add an user to the database.<br>if the database is not protected by user authentication it will enable it. Argument `admin` is an integer identifying if the added user should be an administrator. Only Administrators can add administrators. |
+| `auth_user_change` | username `string`, password `string`, admin `int` | Function to modify an user. Users can change their own password, but only an administrator can change the administrator flag. |
+| `authUserDelete` | username `string` | Delete an user from the database. Can only be used by an administrator. The current logged in administrator cannot be deleted. This is to make sure their is always an administrator remaining. |
+
+These functions will return an integer:
+
+- 0 (SQLITE_OK)
+- 23 (SQLITE_AUTH) Failed to perform due to authentication or insufficient privileges
+
+##### Examples
+
+```sql
+// Autheticate user
+// Create Admin User
+SELECT auth_user_add('admin2', 'admin2', 1);
+
+// Change password for user
+SELECT auth_user_change('user', 'userpassword', 0);
+
+// Delete user
+SELECT user_delete('user');
+```
+
+#### *SQLiteConn
+
+The following functions are available for User authentication from the `*SQLiteConn`:
+
+| Function | Description |
+|----------|-------------|
+| `Authenticate(username, password string) error` | Authenticate user |
+| `AuthUserAdd(username, password string, admin bool) error` | Add user |
+| `AuthUserChange(username, password string, admin bool) error` | Modify user |
+| `AuthUserDelete(username string) error` | Delete user |
+
+### Attached database
+
+When using attached databases, SQLite will use the authentication from the `main` database for the attached database(s).
+
+# Extensions
+
+If you want your own extension to be listed here, or you want to add a reference to an extension; please submit an Issue for this.
+
+## Spatialite
+
+Spatialite is available as an extension to SQLite, and can be used in combination with this repository.
+For an example, see [shaxbee/go-spatialite](https://github.com/shaxbee/go-spatialite).
+
+## extension-functions.c from SQLite3 Contrib
+
+extension-functions.c is available as an extension to SQLite, and provides the following functions:
+
+- Math: acos, asin, atan, atn2, atan2, acosh, asinh, atanh, difference, degrees, radians, cos, sin, tan, cot, cosh, sinh, tanh, coth, exp, log, log10, power, sign, sqrt, square, ceil, floor, pi.
+- String: replicate, charindex, leftstr, rightstr, ltrim, rtrim, trim, replace, reverse, proper, padl, padr, padc, strfilter.
+- Aggregate: stdev, variance, mode, median, lower_quartile, upper_quartile
+
+For an example, see [dinedal/go-sqlite3-extension-functions](https://github.com/dinedal/go-sqlite3-extension-functions).
+
+# FAQ
+
+- Getting insert error while query is opened.
+
+    > You can pass some arguments into the connection string, for example, a URI.
+    > See: [#39](https://github.com/mattn/go-sqlite3/issues/39)
+
+- Do you want to cross compile? mingw on Linux or Mac?
+
+    > See: [#106](https://github.com/mattn/go-sqlite3/issues/106)
+    > See also: http://www.limitlessfx.com/cross-compile-golang-app-for-windows-from-linux.html
+
+- Want to get time.Time with current locale
+
+    Use `_loc=auto` in SQLite3 filename schema like `file:foo.db?_loc=auto`.
+
+- Can I use this in multiple routines concurrently?
+
+    Yes for readonly. But not for writable. See [#50](https://github.com/mattn/go-sqlite3/issues/50), [#51](https://github.com/mattn/go-sqlite3/issues/51), [#209](https://github.com/mattn/go-sqlite3/issues/209), [#274](https://github.com/mattn/go-sqlite3/issues/274).
+
+- Why I'm getting `no such table` error?
+
+    Why is it racy if I use a `sql.Open("sqlite3", ":memory:")` database?
+
+    Each connection to `":memory:"` opens a brand new in-memory sql database, so if
+    the stdlib's sql engine happens to open another connection and you've only
+    specified `":memory:"`, that connection will see a brand new database. A
+    workaround is to use `"file::memory:?cache=shared"` (or `"file:foobar?mode=memory&cache=shared"`). Every
+    connection to this string will point to the same in-memory database.
+    
+    Note that if the last database connection in the pool closes, the in-memory database is deleted. Make sure the [max idle connection limit](https://golang.org/pkg/database/sql/#DB.SetMaxIdleConns) is > 0, and the [connection lifetime](https://golang.org/pkg/database/sql/#DB.SetConnMaxLifetime) is infinite.
+    
+    For more information see:
+    * [#204](https://github.com/mattn/go-sqlite3/issues/204)
+    * [#511](https://github.com/mattn/go-sqlite3/issues/511)
+    * https://www.sqlite.org/sharedcache.html#shared_cache_and_in_memory_databases
+    * https://www.sqlite.org/inmemorydb.html#sharedmemdb
+
+- Reading from database with large amount of goroutines fails on OSX.
+
+    OS X limits OS-wide to not have more than 1000 files open simultaneously by default.
+
+    For more information, see [#289](https://github.com/mattn/go-sqlite3/issues/289)
+
+- Trying to execute a `.` (dot) command throws an error.
+
+    Error: `Error: near ".": syntax error`
+    Dot command are part of SQLite3 CLI, not of this library.
+
+    You need to implement the feature or call the sqlite3 cli.
+
+    More information see [#305](https://github.com/mattn/go-sqlite3/issues/305).
+
+- Error: `database is locked`
+
+    When you get a database is locked, please use the following options.
+
+    Add to DSN: `cache=shared`
+
+    Example:
+    ```go
+    db, err := sql.Open("sqlite3", "file:locked.sqlite?cache=shared")
+    ```
+
+    Next, please set the database connections of the SQL package to 1:
+    
+    ```go
+    db.SetMaxOpenConns(1)
+    ```
+
+    For more information, see [#209](https://github.com/mattn/go-sqlite3/issues/209).
+
+## Contributors
+
+### Code Contributors
+
+This project exists thanks to all the people who [[contribute](CONTRIBUTING.md)].
+<a href="https://github.com/mattn/go-sqlite3/graphs/contributors"><img src="https://opencollective.com/mattn-go-sqlite3/contributors.svg?width=890&button=false" /></a>
+
+### Financial Contributors
+
+Become a financial contributor and help us sustain our community. [[Contribute here](https://opencollective.com/mattn-go-sqlite3/contribute)].
+
+#### Individuals
+
+<a href="https://opencollective.com/mattn-go-sqlite3"><img src="https://opencollective.com/mattn-go-sqlite3/individuals.svg?width=890"></a>
+
+#### Organizations
+
+Support this project with your organization. Your logo will show up here with a link to your website. [[Contribute](https://opencollective.com/mattn-go-sqlite3/contribute)]
+
+<a href="https://opencollective.com/mattn-go-sqlite3/organization/0/website"><img src="https://opencollective.com/mattn-go-sqlite3/organization/0/avatar.svg"></a>
+<a href="https://opencollective.com/mattn-go-sqlite3/organization/1/website"><img src="https://opencollective.com/mattn-go-sqlite3/organization/1/avatar.svg"></a>
+<a href="https://opencollective.com/mattn-go-sqlite3/organization/2/website"><img src="https://opencollective.com/mattn-go-sqlite3/organization/2/avatar.svg"></a>
+<a href="https://opencollective.com/mattn-go-sqlite3/organization/3/website"><img src="https://opencollective.com/mattn-go-sqlite3/organization/3/avatar.svg"></a>
+<a href="https://opencollective.com/mattn-go-sqlite3/organization/4/website"><img src="https://opencollective.com/mattn-go-sqlite3/organization/4/avatar.svg"></a>
+<a href="https://opencollective.com/mattn-go-sqlite3/organization/5/website"><img src="https://opencollective.com/mattn-go-sqlite3/organization/5/avatar.svg"></a>
+<a href="https://opencollective.com/mattn-go-sqlite3/organization/6/website"><img src="https://opencollective.com/mattn-go-sqlite3/organization/6/avatar.svg"></a>
+<a href="https://opencollective.com/mattn-go-sqlite3/organization/7/website"><img src="https://opencollective.com/mattn-go-sqlite3/organization/7/avatar.svg"></a>
+<a href="https://opencollective.com/mattn-go-sqlite3/organization/8/website"><img src="https://opencollective.com/mattn-go-sqlite3/organization/8/avatar.svg"></a>
+<a href="https://opencollective.com/mattn-go-sqlite3/organization/9/website"><img src="https://opencollective.com/mattn-go-sqlite3/organization/9/avatar.svg"></a>
+
+# License
+
+MIT: http://mattn.mit-license.org/2018
+
+sqlite3-binding.c, sqlite3-binding.h, sqlite3ext.h
+
+The -binding suffix was added to avoid build failures under gccgo.
+
+In this repository, those files are an amalgamation of code that was copied from SQLite3. The license of that code is the same as the license of SQLite3.
+
+# Author
+
+Yasuhiro Matsumoto (a.k.a mattn)
+
+G.J.R. Timmer

vendor/github.com/mattn/go-sqlite3/backup.go

@@ -0,0 +1,85 @@
+// Copyright (C) 2019 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+package sqlite3
+
+/*
+#ifndef USE_LIBSQLITE3
+#include "sqlite3-binding.h"
+#else
+#include <sqlite3.h>
+#endif
+#include <stdlib.h>
+*/
+import "C"
+import (
+	"runtime"
+	"unsafe"
+)
+
+// SQLiteBackup implement interface of Backup.
+type SQLiteBackup struct {
+	b *C.sqlite3_backup
+}
+
+// Backup make backup from src to dest.
+func (destConn *SQLiteConn) Backup(dest string, srcConn *SQLiteConn, src string) (*SQLiteBackup, error) {
+	destptr := C.CString(dest)
+	defer C.free(unsafe.Pointer(destptr))
+	srcptr := C.CString(src)
+	defer C.free(unsafe.Pointer(srcptr))
+
+	if b := C.sqlite3_backup_init(destConn.db, destptr, srcConn.db, srcptr); b != nil {
+		bb := &SQLiteBackup{b: b}
+		runtime.SetFinalizer(bb, (*SQLiteBackup).Finish)
+		return bb, nil
+	}
+	return nil, destConn.lastError()
+}
+
+// Step to backs up for one step. Calls the underlying `sqlite3_backup_step`
+// function.  This function returns a boolean indicating if the backup is done
+// and an error signalling any other error. Done is returned if the underlying
+// C function returns SQLITE_DONE (Code 101)
+func (b *SQLiteBackup) Step(p int) (bool, error) {
+	ret := C.sqlite3_backup_step(b.b, C.int(p))
+	if ret == C.SQLITE_DONE {
+		return true, nil
+	} else if ret != 0 && ret != C.SQLITE_LOCKED && ret != C.SQLITE_BUSY {
+		return false, Error{Code: ErrNo(ret)}
+	}
+	return false, nil
+}
+
+// Remaining return whether have the rest for backup.
+func (b *SQLiteBackup) Remaining() int {
+	return int(C.sqlite3_backup_remaining(b.b))
+}
+
+// PageCount return count of pages.
+func (b *SQLiteBackup) PageCount() int {
+	return int(C.sqlite3_backup_pagecount(b.b))
+}
+
+// Finish close backup.
+func (b *SQLiteBackup) Finish() error {
+	return b.Close()
+}
+
+// Close close backup.
+func (b *SQLiteBackup) Close() error {
+	ret := C.sqlite3_backup_finish(b.b)
+
+	// sqlite3_backup_finish() never fails, it just returns the
+	// error code from previous operations, so clean up before
+	// checking and returning an error
+	b.b = nil
+	runtime.SetFinalizer(b, nil)
+
+	if ret != 0 {
+		return Error{Code: ErrNo(ret)}
+	}
+	return nil
+}

vendor/github.com/mattn/go-sqlite3/callback.go

@@ -0,0 +1,411 @@
+// Copyright (C) 2019 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+package sqlite3
+
+// You can't export a Go function to C and have definitions in the C
+// preamble in the same file, so we have to have callbackTrampoline in
+// its own file. Because we need a separate file anyway, the support
+// code for SQLite custom functions is in here.
+
+/*
+#ifndef USE_LIBSQLITE3
+#include "sqlite3-binding.h"
+#else
+#include <sqlite3.h>
+#endif
+#include <stdlib.h>
+
+void _sqlite3_result_text(sqlite3_context* ctx, const char* s);
+void _sqlite3_result_blob(sqlite3_context* ctx, const void* b, int l);
+*/
+import "C"
+
+import (
+	"errors"
+	"fmt"
+	"math"
+	"reflect"
+	"sync"
+	"unsafe"
+)
+
+//export callbackTrampoline
+func callbackTrampoline(ctx *C.sqlite3_context, argc int, argv **C.sqlite3_value) {
+	args := (*[(math.MaxInt32 - 1) / unsafe.Sizeof((*C.sqlite3_value)(nil))]*C.sqlite3_value)(unsafe.Pointer(argv))[:argc:argc]
+	fi := lookupHandle(C.sqlite3_user_data(ctx)).(*functionInfo)
+	fi.Call(ctx, args)
+}
+
+//export stepTrampoline
+func stepTrampoline(ctx *C.sqlite3_context, argc C.int, argv **C.sqlite3_value) {
+	args := (*[(math.MaxInt32 - 1) / unsafe.Sizeof((*C.sqlite3_value)(nil))]*C.sqlite3_value)(unsafe.Pointer(argv))[:int(argc):int(argc)]
+	ai := lookupHandle(C.sqlite3_user_data(ctx)).(*aggInfo)
+	ai.Step(ctx, args)
+}
+
+//export doneTrampoline
+func doneTrampoline(ctx *C.sqlite3_context) {
+	ai := lookupHandle(C.sqlite3_user_data(ctx)).(*aggInfo)
+	ai.Done(ctx)
+}
+
+//export compareTrampoline
+func compareTrampoline(handlePtr unsafe.Pointer, la C.int, a *C.char, lb C.int, b *C.char) C.int {
+	cmp := lookupHandle(handlePtr).(func(string, string) int)
+	return C.int(cmp(C.GoStringN(a, la), C.GoStringN(b, lb)))
+}
+
+//export commitHookTrampoline
+func commitHookTrampoline(handle unsafe.Pointer) int {
+	callback := lookupHandle(handle).(func() int)
+	return callback()
+}
+
+//export rollbackHookTrampoline
+func rollbackHookTrampoline(handle unsafe.Pointer) {
+	callback := lookupHandle(handle).(func())
+	callback()
+}
+
+//export updateHookTrampoline
+func updateHookTrampoline(handle unsafe.Pointer, op int, db *C.char, table *C.char, rowid int64) {
+	callback := lookupHandle(handle).(func(int, string, string, int64))
+	callback(op, C.GoString(db), C.GoString(table), rowid)
+}
+
+//export authorizerTrampoline
+func authorizerTrampoline(handle unsafe.Pointer, op int, arg1 *C.char, arg2 *C.char, arg3 *C.char) int {
+	callback := lookupHandle(handle).(func(int, string, string, string) int)
+	return callback(op, C.GoString(arg1), C.GoString(arg2), C.GoString(arg3))
+}
+
+//export preUpdateHookTrampoline
+func preUpdateHookTrampoline(handle unsafe.Pointer, dbHandle uintptr, op int, db *C.char, table *C.char, oldrowid int64, newrowid int64) {
+	hval := lookupHandleVal(handle)
+	data := SQLitePreUpdateData{
+		Conn:         hval.db,
+		Op:           op,
+		DatabaseName: C.GoString(db),
+		TableName:    C.GoString(table),
+		OldRowID:     oldrowid,
+		NewRowID:     newrowid,
+	}
+	callback := hval.val.(func(SQLitePreUpdateData))
+	callback(data)
+}
+
+// Use handles to avoid passing Go pointers to C.
+type handleVal struct {
+	db  *SQLiteConn
+	val interface{}
+}
+
+var handleLock sync.Mutex
+var handleVals = make(map[unsafe.Pointer]handleVal)
+
+func newHandle(db *SQLiteConn, v interface{}) unsafe.Pointer {
+	handleLock.Lock()
+	defer handleLock.Unlock()
+	val := handleVal{db: db, val: v}
+	var p unsafe.Pointer = C.malloc(C.size_t(1))
+	if p == nil {
+		panic("can't allocate 'cgo-pointer hack index pointer': ptr == nil")
+	}
+	handleVals[p] = val
+	return p
+}
+
+func lookupHandleVal(handle unsafe.Pointer) handleVal {
+	handleLock.Lock()
+	defer handleLock.Unlock()
+	return handleVals[handle]
+}
+
+func lookupHandle(handle unsafe.Pointer) interface{} {
+	return lookupHandleVal(handle).val
+}
+
+func deleteHandles(db *SQLiteConn) {
+	handleLock.Lock()
+	defer handleLock.Unlock()
+	for handle, val := range handleVals {
+		if val.db == db {
+			delete(handleVals, handle)
+			C.free(handle)
+		}
+	}
+}
+
+// This is only here so that tests can refer to it.
+type callbackArgRaw C.sqlite3_value
+
+type callbackArgConverter func(*C.sqlite3_value) (reflect.Value, error)
+
+type callbackArgCast struct {
+	f   callbackArgConverter
+	typ reflect.Type
+}
+
+func (c callbackArgCast) Run(v *C.sqlite3_value) (reflect.Value, error) {
+	val, err := c.f(v)
+	if err != nil {
+		return reflect.Value{}, err
+	}
+	if !val.Type().ConvertibleTo(c.typ) {
+		return reflect.Value{}, fmt.Errorf("cannot convert %s to %s", val.Type(), c.typ)
+	}
+	return val.Convert(c.typ), nil
+}
+
+func callbackArgInt64(v *C.sqlite3_value) (reflect.Value, error) {
+	if C.sqlite3_value_type(v) != C.SQLITE_INTEGER {
+		return reflect.Value{}, fmt.Errorf("argument must be an INTEGER")
+	}
+	return reflect.ValueOf(int64(C.sqlite3_value_int64(v))), nil
+}
+
+func callbackArgBool(v *C.sqlite3_value) (reflect.Value, error) {
+	if C.sqlite3_value_type(v) != C.SQLITE_INTEGER {
+		return reflect.Value{}, fmt.Errorf("argument must be an INTEGER")
+	}
+	i := int64(C.sqlite3_value_int64(v))
+	val := false
+	if i != 0 {
+		val = true
+	}
+	return reflect.ValueOf(val), nil
+}
+
+func callbackArgFloat64(v *C.sqlite3_value) (reflect.Value, error) {
+	if C.sqlite3_value_type(v) != C.SQLITE_FLOAT {
+		return reflect.Value{}, fmt.Errorf("argument must be a FLOAT")
+	}
+	return reflect.ValueOf(float64(C.sqlite3_value_double(v))), nil
+}
+
+func callbackArgBytes(v *C.sqlite3_value) (reflect.Value, error) {
+	switch C.sqlite3_value_type(v) {
+	case C.SQLITE_BLOB:
+		l := C.sqlite3_value_bytes(v)
+		p := C.sqlite3_value_blob(v)
+		return reflect.ValueOf(C.GoBytes(p, l)), nil
+	case C.SQLITE_TEXT:
+		l := C.sqlite3_value_bytes(v)
+		c := unsafe.Pointer(C.sqlite3_value_text(v))
+		return reflect.ValueOf(C.GoBytes(c, l)), nil
+	default:
+		return reflect.Value{}, fmt.Errorf("argument must be BLOB or TEXT")
+	}
+}
+
+func callbackArgString(v *C.sqlite3_value) (reflect.Value, error) {
+	switch C.sqlite3_value_type(v) {
+	case C.SQLITE_BLOB:
+		l := C.sqlite3_value_bytes(v)
+		p := (*C.char)(C.sqlite3_value_blob(v))
+		return reflect.ValueOf(C.GoStringN(p, l)), nil
+	case C.SQLITE_TEXT:
+		c := (*C.char)(unsafe.Pointer(C.sqlite3_value_text(v)))
+		return reflect.ValueOf(C.GoString(c)), nil
+	default:
+		return reflect.Value{}, fmt.Errorf("argument must be BLOB or TEXT")
+	}
+}
+
+func callbackArgGeneric(v *C.sqlite3_value) (reflect.Value, error) {
+	switch C.sqlite3_value_type(v) {
+	case C.SQLITE_INTEGER:
+		return callbackArgInt64(v)
+	case C.SQLITE_FLOAT:
+		return callbackArgFloat64(v)
+	case C.SQLITE_TEXT:
+		return callbackArgString(v)
+	case C.SQLITE_BLOB:
+		return callbackArgBytes(v)
+	case C.SQLITE_NULL:
+		// Interpret NULL as a nil byte slice.
+		var ret []byte
+		return reflect.ValueOf(ret), nil
+	default:
+		panic("unreachable")
+	}
+}
+
+func callbackArg(typ reflect.Type) (callbackArgConverter, error) {
+	switch typ.Kind() {
+	case reflect.Interface:
+		if typ.NumMethod() != 0 {
+			return nil, errors.New("the only supported interface type is interface{}")
+		}
+		return callbackArgGeneric, nil
+	case reflect.Slice:
+		if typ.Elem().Kind() != reflect.Uint8 {
+			return nil, errors.New("the only supported slice type is []byte")
+		}
+		return callbackArgBytes, nil
+	case reflect.String:
+		return callbackArgString, nil
+	case reflect.Bool:
+		return callbackArgBool, nil
+	case reflect.Int64:
+		return callbackArgInt64, nil
+	case reflect.Int8, reflect.Int16, reflect.Int32, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Int, reflect.Uint:
+		c := callbackArgCast{callbackArgInt64, typ}
+		return c.Run, nil
+	case reflect.Float64:
+		return callbackArgFloat64, nil
+	case reflect.Float32:
+		c := callbackArgCast{callbackArgFloat64, typ}
+		return c.Run, nil
+	default:
+		return nil, fmt.Errorf("don't know how to convert to %s", typ)
+	}
+}
+
+func callbackConvertArgs(argv []*C.sqlite3_value, converters []callbackArgConverter, variadic callbackArgConverter) ([]reflect.Value, error) {
+	var args []reflect.Value
+
+	if len(argv) < len(converters) {
+		return nil, fmt.Errorf("function requires at least %d arguments", len(converters))
+	}
+
+	for i, arg := range argv[:len(converters)] {
+		v, err := converters[i](arg)
+		if err != nil {
+			return nil, err
+		}
+		args = append(args, v)
+	}
+
+	if variadic != nil {
+		for _, arg := range argv[len(converters):] {
+			v, err := variadic(arg)
+			if err != nil {
+				return nil, err
+			}
+			args = append(args, v)
+		}
+	}
+	return args, nil
+}
+
+type callbackRetConverter func(*C.sqlite3_context, reflect.Value) error
+
+func callbackRetInteger(ctx *C.sqlite3_context, v reflect.Value) error {
+	switch v.Type().Kind() {
+	case reflect.Int64:
+	case reflect.Int8, reflect.Int16, reflect.Int32, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Int, reflect.Uint:
+		v = v.Convert(reflect.TypeOf(int64(0)))
+	case reflect.Bool:
+		b := v.Interface().(bool)
+		if b {
+			v = reflect.ValueOf(int64(1))
+		} else {
+			v = reflect.ValueOf(int64(0))
+		}
+	default:
+		return fmt.Errorf("cannot convert %s to INTEGER", v.Type())
+	}
+
+	C.sqlite3_result_int64(ctx, C.sqlite3_int64(v.Interface().(int64)))
+	return nil
+}
+
+func callbackRetFloat(ctx *C.sqlite3_context, v reflect.Value) error {
+	switch v.Type().Kind() {
+	case reflect.Float64:
+	case reflect.Float32:
+		v = v.Convert(reflect.TypeOf(float64(0)))
+	default:
+		return fmt.Errorf("cannot convert %s to FLOAT", v.Type())
+	}
+
+	C.sqlite3_result_double(ctx, C.double(v.Interface().(float64)))
+	return nil
+}
+
+func callbackRetBlob(ctx *C.sqlite3_context, v reflect.Value) error {
+	if v.Type().Kind() != reflect.Slice || v.Type().Elem().Kind() != reflect.Uint8 {
+		return fmt.Errorf("cannot convert %s to BLOB", v.Type())
+	}
+	i := v.Interface()
+	if i == nil || len(i.([]byte)) == 0 {
+		C.sqlite3_result_null(ctx)
+	} else {
+		bs := i.([]byte)
+		C._sqlite3_result_blob(ctx, unsafe.Pointer(&bs[0]), C.int(len(bs)))
+	}
+	return nil
+}
+
+func callbackRetText(ctx *C.sqlite3_context, v reflect.Value) error {
+	if v.Type().Kind() != reflect.String {
+		return fmt.Errorf("cannot convert %s to TEXT", v.Type())
+	}
+	C._sqlite3_result_text(ctx, C.CString(v.Interface().(string)))
+	return nil
+}
+
+func callbackRetNil(ctx *C.sqlite3_context, v reflect.Value) error {
+	return nil
+}
+
+func callbackRetGeneric(ctx *C.sqlite3_context, v reflect.Value) error {
+	if v.IsNil() {
+		C.sqlite3_result_null(ctx)
+		return nil
+	}
+
+	cb, err := callbackRet(v.Elem().Type())
+        if err != nil {
+                return err
+        }
+
+        return cb(ctx, v.Elem())
+}
+
+func callbackRet(typ reflect.Type) (callbackRetConverter, error) {
+	switch typ.Kind() {
+	case reflect.Interface:
+		errorInterface := reflect.TypeOf((*error)(nil)).Elem()
+		if typ.Implements(errorInterface) {
+			return callbackRetNil, nil
+		}
+
+		if typ.NumMethod() == 0 {
+			return callbackRetGeneric, nil
+		}
+
+		fallthrough
+	case reflect.Slice:
+		if typ.Elem().Kind() != reflect.Uint8 {
+			return nil, errors.New("the only supported slice type is []byte")
+		}
+		return callbackRetBlob, nil
+	case reflect.String:
+		return callbackRetText, nil
+	case reflect.Bool, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Int, reflect.Uint:
+		return callbackRetInteger, nil
+	case reflect.Float32, reflect.Float64:
+		return callbackRetFloat, nil
+	default:
+		return nil, fmt.Errorf("don't know how to convert to %s", typ)
+	}
+}
+
+func callbackError(ctx *C.sqlite3_context, err error) {
+	cstr := C.CString(err.Error())
+	defer C.free(unsafe.Pointer(cstr))
+	C.sqlite3_result_error(ctx, cstr, C.int(-1))
+}
+
+// Test support code. Tests are not allowed to import "C", so we can't
+// declare any functions that use C.sqlite3_value.
+func callbackSyntheticForTests(v reflect.Value, err error) callbackArgConverter {
+	return func(*C.sqlite3_value) (reflect.Value, error) {
+		return v, err
+	}
+}

vendor/github.com/mattn/go-sqlite3/convert.go

@@ -0,0 +1,299 @@
+// Extracted from Go database/sql source code
+
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Type conversions for Scan.
+
+package sqlite3
+
+import (
+	"database/sql"
+	"database/sql/driver"
+	"errors"
+	"fmt"
+	"reflect"
+	"strconv"
+	"time"
+)
+
+var errNilPtr = errors.New("destination pointer is nil") // embedded in descriptive error
+
+// convertAssign copies to dest the value in src, converting it if possible.
+// An error is returned if the copy would result in loss of information.
+// dest should be a pointer type.
+func convertAssign(dest, src interface{}) error {
+	// Common cases, without reflect.
+	switch s := src.(type) {
+	case string:
+		switch d := dest.(type) {
+		case *string:
+			if d == nil {
+				return errNilPtr
+			}
+			*d = s
+			return nil
+		case *[]byte:
+			if d == nil {
+				return errNilPtr
+			}
+			*d = []byte(s)
+			return nil
+		case *sql.RawBytes:
+			if d == nil {
+				return errNilPtr
+			}
+			*d = append((*d)[:0], s...)
+			return nil
+		}
+	case []byte:
+		switch d := dest.(type) {
+		case *string:
+			if d == nil {
+				return errNilPtr
+			}
+			*d = string(s)
+			return nil
+		case *interface{}:
+			if d == nil {
+				return errNilPtr
+			}
+			*d = cloneBytes(s)
+			return nil
+		case *[]byte:
+			if d == nil {
+				return errNilPtr
+			}
+			*d = cloneBytes(s)
+			return nil
+		case *sql.RawBytes:
+			if d == nil {
+				return errNilPtr
+			}
+			*d = s
+			return nil
+		}
+	case time.Time:
+		switch d := dest.(type) {
+		case *time.Time:
+			*d = s
+			return nil
+		case *string:
+			*d = s.Format(time.RFC3339Nano)
+			return nil
+		case *[]byte:
+			if d == nil {
+				return errNilPtr
+			}
+			*d = []byte(s.Format(time.RFC3339Nano))
+			return nil
+		case *sql.RawBytes:
+			if d == nil {
+				return errNilPtr
+			}
+			*d = s.AppendFormat((*d)[:0], time.RFC3339Nano)
+			return nil
+		}
+	case nil:
+		switch d := dest.(type) {
+		case *interface{}:
+			if d == nil {
+				return errNilPtr
+			}
+			*d = nil
+			return nil
+		case *[]byte:
+			if d == nil {
+				return errNilPtr
+			}
+			*d = nil
+			return nil
+		case *sql.RawBytes:
+			if d == nil {
+				return errNilPtr
+			}
+			*d = nil
+			return nil
+		}
+	}
+
+	var sv reflect.Value
+
+	switch d := dest.(type) {
+	case *string:
+		sv = reflect.ValueOf(src)
+		switch sv.Kind() {
+		case reflect.Bool,
+			reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64,
+			reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64,
+			reflect.Float32, reflect.Float64:
+			*d = asString(src)
+			return nil
+		}
+	case *[]byte:
+		sv = reflect.ValueOf(src)
+		if b, ok := asBytes(nil, sv); ok {
+			*d = b
+			return nil
+		}
+	case *sql.RawBytes:
+		sv = reflect.ValueOf(src)
+		if b, ok := asBytes([]byte(*d)[:0], sv); ok {
+			*d = sql.RawBytes(b)
+			return nil
+		}
+	case *bool:
+		bv, err := driver.Bool.ConvertValue(src)
+		if err == nil {
+			*d = bv.(bool)
+		}
+		return err
+	case *interface{}:
+		*d = src
+		return nil
+	}
+
+	if scanner, ok := dest.(sql.Scanner); ok {
+		return scanner.Scan(src)
+	}
+
+	dpv := reflect.ValueOf(dest)
+	if dpv.Kind() != reflect.Ptr {
+		return errors.New("destination not a pointer")
+	}
+	if dpv.IsNil() {
+		return errNilPtr
+	}
+
+	if !sv.IsValid() {
+		sv = reflect.ValueOf(src)
+	}
+
+	dv := reflect.Indirect(dpv)
+	if sv.IsValid() && sv.Type().AssignableTo(dv.Type()) {
+		switch b := src.(type) {
+		case []byte:
+			dv.Set(reflect.ValueOf(cloneBytes(b)))
+		default:
+			dv.Set(sv)
+		}
+		return nil
+	}
+
+	if dv.Kind() == sv.Kind() && sv.Type().ConvertibleTo(dv.Type()) {
+		dv.Set(sv.Convert(dv.Type()))
+		return nil
+	}
+
+	// The following conversions use a string value as an intermediate representation
+	// to convert between various numeric types.
+	//
+	// This also allows scanning into user defined types such as "type Int int64".
+	// For symmetry, also check for string destination types.
+	switch dv.Kind() {
+	case reflect.Ptr:
+		if src == nil {
+			dv.Set(reflect.Zero(dv.Type()))
+			return nil
+		}
+		dv.Set(reflect.New(dv.Type().Elem()))
+		return convertAssign(dv.Interface(), src)
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		s := asString(src)
+		i64, err := strconv.ParseInt(s, 10, dv.Type().Bits())
+		if err != nil {
+			err = strconvErr(err)
+			return fmt.Errorf("converting driver.Value type %T (%q) to a %s: %v", src, s, dv.Kind(), err)
+		}
+		dv.SetInt(i64)
+		return nil
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+		s := asString(src)
+		u64, err := strconv.ParseUint(s, 10, dv.Type().Bits())
+		if err != nil {
+			err = strconvErr(err)
+			return fmt.Errorf("converting driver.Value type %T (%q) to a %s: %v", src, s, dv.Kind(), err)
+		}
+		dv.SetUint(u64)
+		return nil
+	case reflect.Float32, reflect.Float64:
+		s := asString(src)
+		f64, err := strconv.ParseFloat(s, dv.Type().Bits())
+		if err != nil {
+			err = strconvErr(err)
+			return fmt.Errorf("converting driver.Value type %T (%q) to a %s: %v", src, s, dv.Kind(), err)
+		}
+		dv.SetFloat(f64)
+		return nil
+	case reflect.String:
+		switch v := src.(type) {
+		case string:
+			dv.SetString(v)
+			return nil
+		case []byte:
+			dv.SetString(string(v))
+			return nil
+		}
+	}
+
+	return fmt.Errorf("unsupported Scan, storing driver.Value type %T into type %T", src, dest)
+}
+
+func strconvErr(err error) error {
+	if ne, ok := err.(*strconv.NumError); ok {
+		return ne.Err
+	}
+	return err
+}
+
+func cloneBytes(b []byte) []byte {
+	if b == nil {
+		return nil
+	}
+	c := make([]byte, len(b))
+	copy(c, b)
+	return c
+}
+
+func asString(src interface{}) string {
+	switch v := src.(type) {
+	case string:
+		return v
+	case []byte:
+		return string(v)
+	}
+	rv := reflect.ValueOf(src)
+	switch rv.Kind() {
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return strconv.FormatInt(rv.Int(), 10)
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+		return strconv.FormatUint(rv.Uint(), 10)
+	case reflect.Float64:
+		return strconv.FormatFloat(rv.Float(), 'g', -1, 64)
+	case reflect.Float32:
+		return strconv.FormatFloat(rv.Float(), 'g', -1, 32)
+	case reflect.Bool:
+		return strconv.FormatBool(rv.Bool())
+	}
+	return fmt.Sprintf("%v", src)
+}
+
+func asBytes(buf []byte, rv reflect.Value) (b []byte, ok bool) {
+	switch rv.Kind() {
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return strconv.AppendInt(buf, rv.Int(), 10), true
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+		return strconv.AppendUint(buf, rv.Uint(), 10), true
+	case reflect.Float32:
+		return strconv.AppendFloat(buf, rv.Float(), 'g', -1, 32), true
+	case reflect.Float64:
+		return strconv.AppendFloat(buf, rv.Float(), 'g', -1, 64), true
+	case reflect.Bool:
+		return strconv.AppendBool(buf, rv.Bool()), true
+	case reflect.String:
+		s := rv.String()
+		return append(buf, s...), true
+	}
+	return
+}

vendor/github.com/mattn/go-sqlite3/doc.go

@@ -0,0 +1,135 @@
+/*
+Package sqlite3 provides interface to SQLite3 databases.
+
+This works as a driver for database/sql.
+
+Installation
+
+    go get github.com/mattn/go-sqlite3
+
+Supported Types
+
+Currently, go-sqlite3 supports the following data types.
+
+    +------------------------------+
+    |go        | sqlite3           |
+    |----------|-------------------|
+    |nil       | null              |
+    |int       | integer           |
+    |int64     | integer           |
+    |float64   | float             |
+    |bool      | integer           |
+    |[]byte    | blob              |
+    |string    | text              |
+    |time.Time | timestamp/datetime|
+    +------------------------------+
+
+SQLite3 Extension
+
+You can write your own extension module for sqlite3. For example, below is an
+extension for a Regexp matcher operation.
+
+    #include <pcre.h>
+    #include <string.h>
+    #include <stdio.h>
+    #include <sqlite3ext.h>
+
+    SQLITE_EXTENSION_INIT1
+    static void regexp_func(sqlite3_context *context, int argc, sqlite3_value **argv) {
+      if (argc >= 2) {
+        const char *target  = (const char *)sqlite3_value_text(argv[1]);
+        const char *pattern = (const char *)sqlite3_value_text(argv[0]);
+        const char* errstr = NULL;
+        int erroff = 0;
+        int vec[500];
+        int n, rc;
+        pcre* re = pcre_compile(pattern, 0, &errstr, &erroff, NULL);
+        rc = pcre_exec(re, NULL, target, strlen(target), 0, 0, vec, 500);
+        if (rc <= 0) {
+          sqlite3_result_error(context, errstr, 0);
+          return;
+        }
+        sqlite3_result_int(context, 1);
+      }
+    }
+
+    #ifdef _WIN32
+    __declspec(dllexport)
+    #endif
+    int sqlite3_extension_init(sqlite3 *db, char **errmsg,
+          const sqlite3_api_routines *api) {
+      SQLITE_EXTENSION_INIT2(api);
+      return sqlite3_create_function(db, "regexp", 2, SQLITE_UTF8,
+          (void*)db, regexp_func, NULL, NULL);
+    }
+
+It needs to be built as a so/dll shared library. And you need to register
+the extension module like below.
+
+	sql.Register("sqlite3_with_extensions",
+		&sqlite3.SQLiteDriver{
+			Extensions: []string{
+				"sqlite3_mod_regexp",
+			},
+		})
+
+Then, you can use this extension.
+
+	rows, err := db.Query("select text from mytable where name regexp '^golang'")
+
+Connection Hook
+
+You can hook and inject your code when the connection is established by setting
+ConnectHook to get the SQLiteConn.
+
+	sql.Register("sqlite3_with_hook_example",
+			&sqlite3.SQLiteDriver{
+					ConnectHook: func(conn *sqlite3.SQLiteConn) error {
+						sqlite3conn = append(sqlite3conn, conn)
+						return nil
+					},
+			})
+
+You can also use database/sql.Conn.Raw (Go >= 1.13):
+
+	conn, err := db.Conn(context.Background())
+	// if err != nil { ... }
+	defer conn.Close()
+	err = conn.Raw(func (driverConn interface{}) error {
+		sqliteConn := driverConn.(*sqlite3.SQLiteConn)
+		// ... use sqliteConn
+	})
+	// if err != nil { ... }
+
+Go SQlite3 Extensions
+
+If you want to register Go functions as SQLite extension functions
+you can make a custom driver by calling RegisterFunction from
+ConnectHook.
+
+	regex = func(re, s string) (bool, error) {
+		return regexp.MatchString(re, s)
+	}
+	sql.Register("sqlite3_extended",
+			&sqlite3.SQLiteDriver{
+					ConnectHook: func(conn *sqlite3.SQLiteConn) error {
+						return conn.RegisterFunc("regexp", regex, true)
+					},
+			})
+
+You can then use the custom driver by passing its name to sql.Open.
+
+	var i int
+	conn, err := sql.Open("sqlite3_extended", "./foo.db")
+	if err != nil {
+		panic(err)
+	}
+	err = db.QueryRow(`SELECT regexp("foo.*", "seafood")`).Scan(&i)
+	if err != nil {
+		panic(err)
+	}
+
+See the documentation of RegisterFunc for more details.
+
+*/
+package sqlite3

vendor/github.com/mattn/go-sqlite3/error.go

@@ -0,0 +1,150 @@
+// Copyright (C) 2019 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+package sqlite3
+
+/*
+#ifndef USE_LIBSQLITE3
+#include "sqlite3-binding.h"
+#else
+#include <sqlite3.h>
+#endif
+*/
+import "C"
+import "syscall"
+
+// ErrNo inherit errno.
+type ErrNo int
+
+// ErrNoMask is mask code.
+const ErrNoMask C.int = 0xff
+
+// ErrNoExtended is extended errno.
+type ErrNoExtended int
+
+// Error implement sqlite error code.
+type Error struct {
+	Code         ErrNo         /* The error code returned by SQLite */
+	ExtendedCode ErrNoExtended /* The extended error code returned by SQLite */
+	SystemErrno  syscall.Errno /* The system errno returned by the OS through SQLite, if applicable */
+	err          string        /* The error string returned by sqlite3_errmsg(),
+	this usually contains more specific details. */
+}
+
+// result codes from http://www.sqlite.org/c3ref/c_abort.html
+var (
+	ErrError      = ErrNo(1)  /* SQL error or missing database */
+	ErrInternal   = ErrNo(2)  /* Internal logic error in SQLite */
+	ErrPerm       = ErrNo(3)  /* Access permission denied */
+	ErrAbort      = ErrNo(4)  /* Callback routine requested an abort */
+	ErrBusy       = ErrNo(5)  /* The database file is locked */
+	ErrLocked     = ErrNo(6)  /* A table in the database is locked */
+	ErrNomem      = ErrNo(7)  /* A malloc() failed */
+	ErrReadonly   = ErrNo(8)  /* Attempt to write a readonly database */
+	ErrInterrupt  = ErrNo(9)  /* Operation terminated by sqlite3_interrupt() */
+	ErrIoErr      = ErrNo(10) /* Some kind of disk I/O error occurred */
+	ErrCorrupt    = ErrNo(11) /* The database disk image is malformed */
+	ErrNotFound   = ErrNo(12) /* Unknown opcode in sqlite3_file_control() */
+	ErrFull       = ErrNo(13) /* Insertion failed because database is full */
+	ErrCantOpen   = ErrNo(14) /* Unable to open the database file */
+	ErrProtocol   = ErrNo(15) /* Database lock protocol error */
+	ErrEmpty      = ErrNo(16) /* Database is empty */
+	ErrSchema     = ErrNo(17) /* The database schema changed */
+	ErrTooBig     = ErrNo(18) /* String or BLOB exceeds size limit */
+	ErrConstraint = ErrNo(19) /* Abort due to constraint violation */
+	ErrMismatch   = ErrNo(20) /* Data type mismatch */
+	ErrMisuse     = ErrNo(21) /* Library used incorrectly */
+	ErrNoLFS      = ErrNo(22) /* Uses OS features not supported on host */
+	ErrAuth       = ErrNo(23) /* Authorization denied */
+	ErrFormat     = ErrNo(24) /* Auxiliary database format error */
+	ErrRange      = ErrNo(25) /* 2nd parameter to sqlite3_bind out of range */
+	ErrNotADB     = ErrNo(26) /* File opened that is not a database file */
+	ErrNotice     = ErrNo(27) /* Notifications from sqlite3_log() */
+	ErrWarning    = ErrNo(28) /* Warnings from sqlite3_log() */
+)
+
+// Error return error message from errno.
+func (err ErrNo) Error() string {
+	return Error{Code: err}.Error()
+}
+
+// Extend return extended errno.
+func (err ErrNo) Extend(by int) ErrNoExtended {
+	return ErrNoExtended(int(err) | (by << 8))
+}
+
+// Error return error message that is extended code.
+func (err ErrNoExtended) Error() string {
+	return Error{Code: ErrNo(C.int(err) & ErrNoMask), ExtendedCode: err}.Error()
+}
+
+func (err Error) Error() string {
+	var str string
+	if err.err != "" {
+		str = err.err
+	} else {
+		str = C.GoString(C.sqlite3_errstr(C.int(err.Code)))
+	}
+	if err.SystemErrno != 0 {
+		str += ": " + err.SystemErrno.Error()
+	}
+	return str
+}
+
+// result codes from http://www.sqlite.org/c3ref/c_abort_rollback.html
+var (
+	ErrIoErrRead              = ErrIoErr.Extend(1)
+	ErrIoErrShortRead         = ErrIoErr.Extend(2)
+	ErrIoErrWrite             = ErrIoErr.Extend(3)
+	ErrIoErrFsync             = ErrIoErr.Extend(4)
+	ErrIoErrDirFsync          = ErrIoErr.Extend(5)
+	ErrIoErrTruncate          = ErrIoErr.Extend(6)
+	ErrIoErrFstat             = ErrIoErr.Extend(7)
+	ErrIoErrUnlock            = ErrIoErr.Extend(8)
+	ErrIoErrRDlock            = ErrIoErr.Extend(9)
+	ErrIoErrDelete            = ErrIoErr.Extend(10)
+	ErrIoErrBlocked           = ErrIoErr.Extend(11)
+	ErrIoErrNoMem             = ErrIoErr.Extend(12)
+	ErrIoErrAccess            = ErrIoErr.Extend(13)
+	ErrIoErrCheckReservedLock = ErrIoErr.Extend(14)
+	ErrIoErrLock              = ErrIoErr.Extend(15)
+	ErrIoErrClose             = ErrIoErr.Extend(16)
+	ErrIoErrDirClose          = ErrIoErr.Extend(17)
+	ErrIoErrSHMOpen           = ErrIoErr.Extend(18)
+	ErrIoErrSHMSize           = ErrIoErr.Extend(19)
+	ErrIoErrSHMLock           = ErrIoErr.Extend(20)
+	ErrIoErrSHMMap            = ErrIoErr.Extend(21)
+	ErrIoErrSeek              = ErrIoErr.Extend(22)
+	ErrIoErrDeleteNoent       = ErrIoErr.Extend(23)
+	ErrIoErrMMap              = ErrIoErr.Extend(24)
+	ErrIoErrGetTempPath       = ErrIoErr.Extend(25)
+	ErrIoErrConvPath          = ErrIoErr.Extend(26)
+	ErrLockedSharedCache      = ErrLocked.Extend(1)
+	ErrBusyRecovery           = ErrBusy.Extend(1)
+	ErrBusySnapshot           = ErrBusy.Extend(2)
+	ErrCantOpenNoTempDir      = ErrCantOpen.Extend(1)
+	ErrCantOpenIsDir          = ErrCantOpen.Extend(2)
+	ErrCantOpenFullPath       = ErrCantOpen.Extend(3)
+	ErrCantOpenConvPath       = ErrCantOpen.Extend(4)
+	ErrCorruptVTab            = ErrCorrupt.Extend(1)
+	ErrReadonlyRecovery       = ErrReadonly.Extend(1)
+	ErrReadonlyCantLock       = ErrReadonly.Extend(2)
+	ErrReadonlyRollback       = ErrReadonly.Extend(3)
+	ErrReadonlyDbMoved        = ErrReadonly.Extend(4)
+	ErrAbortRollback          = ErrAbort.Extend(2)
+	ErrConstraintCheck        = ErrConstraint.Extend(1)
+	ErrConstraintCommitHook   = ErrConstraint.Extend(2)
+	ErrConstraintForeignKey   = ErrConstraint.Extend(3)
+	ErrConstraintFunction     = ErrConstraint.Extend(4)
+	ErrConstraintNotNull      = ErrConstraint.Extend(5)
+	ErrConstraintPrimaryKey   = ErrConstraint.Extend(6)
+	ErrConstraintTrigger      = ErrConstraint.Extend(7)
+	ErrConstraintUnique       = ErrConstraint.Extend(8)
+	ErrConstraintVTab         = ErrConstraint.Extend(9)
+	ErrConstraintRowID        = ErrConstraint.Extend(10)
+	ErrNoticeRecoverWAL       = ErrNotice.Extend(1)
+	ErrNoticeRecoverRollback  = ErrNotice.Extend(2)
+	ErrWarningAutoIndex       = ErrWarning.Extend(1)
+)

vendor/github.com/mattn/go-sqlite3/sqlite3_context.go

@@ -0,0 +1,103 @@
+// Copyright (C) 2019 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+package sqlite3
+
+/*
+
+#ifndef USE_LIBSQLITE3
+#include "sqlite3-binding.h"
+#else
+#include <sqlite3.h>
+#endif
+#include <stdlib.h>
+// These wrappers are necessary because SQLITE_TRANSIENT
+// is a pointer constant, and cgo doesn't translate them correctly.
+
+static inline void my_result_text(sqlite3_context *ctx, char *p, int np) {
+	sqlite3_result_text(ctx, p, np, SQLITE_TRANSIENT);
+}
+
+static inline void my_result_blob(sqlite3_context *ctx, void *p, int np) {
+	sqlite3_result_blob(ctx, p, np, SQLITE_TRANSIENT);
+}
+*/
+import "C"
+
+import (
+	"math"
+	"reflect"
+	"unsafe"
+)
+
+const i64 = unsafe.Sizeof(int(0)) > 4
+
+// SQLiteContext behave sqlite3_context
+type SQLiteContext C.sqlite3_context
+
+// ResultBool sets the result of an SQL function.
+func (c *SQLiteContext) ResultBool(b bool) {
+	if b {
+		c.ResultInt(1)
+	} else {
+		c.ResultInt(0)
+	}
+}
+
+// ResultBlob sets the result of an SQL function.
+// See: sqlite3_result_blob, http://sqlite.org/c3ref/result_blob.html
+func (c *SQLiteContext) ResultBlob(b []byte) {
+	if i64 && len(b) > math.MaxInt32 {
+		C.sqlite3_result_error_toobig((*C.sqlite3_context)(c))
+		return
+	}
+	var p *byte
+	if len(b) > 0 {
+		p = &b[0]
+	}
+	C.my_result_blob((*C.sqlite3_context)(c), unsafe.Pointer(p), C.int(len(b)))
+}
+
+// ResultDouble sets the result of an SQL function.
+// See: sqlite3_result_double, http://sqlite.org/c3ref/result_blob.html
+func (c *SQLiteContext) ResultDouble(d float64) {
+	C.sqlite3_result_double((*C.sqlite3_context)(c), C.double(d))
+}
+
+// ResultInt sets the result of an SQL function.
+// See: sqlite3_result_int, http://sqlite.org/c3ref/result_blob.html
+func (c *SQLiteContext) ResultInt(i int) {
+	if i64 && (i > math.MaxInt32 || i < math.MinInt32) {
+		C.sqlite3_result_int64((*C.sqlite3_context)(c), C.sqlite3_int64(i))
+	} else {
+		C.sqlite3_result_int((*C.sqlite3_context)(c), C.int(i))
+	}
+}
+
+// ResultInt64 sets the result of an SQL function.
+// See: sqlite3_result_int64, http://sqlite.org/c3ref/result_blob.html
+func (c *SQLiteContext) ResultInt64(i int64) {
+	C.sqlite3_result_int64((*C.sqlite3_context)(c), C.sqlite3_int64(i))
+}
+
+// ResultNull sets the result of an SQL function.
+// See: sqlite3_result_null, http://sqlite.org/c3ref/result_blob.html
+func (c *SQLiteContext) ResultNull() {
+	C.sqlite3_result_null((*C.sqlite3_context)(c))
+}
+
+// ResultText sets the result of an SQL function.
+// See: sqlite3_result_text, http://sqlite.org/c3ref/result_blob.html
+func (c *SQLiteContext) ResultText(s string) {
+	h := (*reflect.StringHeader)(unsafe.Pointer(&s))
+	cs, l := (*C.char)(unsafe.Pointer(h.Data)), C.int(h.Len)
+	C.my_result_text((*C.sqlite3_context)(c), cs, l)
+}
+
+// ResultZeroblob sets the result of an SQL function.
+// See: sqlite3_result_zeroblob, http://sqlite.org/c3ref/result_blob.html
+func (c *SQLiteContext) ResultZeroblob(n int) {
+	C.sqlite3_result_zeroblob((*C.sqlite3_context)(c), C.int(n))
+}

vendor/github.com/mattn/go-sqlite3/sqlite3_func_crypt.go

@@ -0,0 +1,120 @@
+// Copyright (C) 2018 G.J.R. Timmer <gjr.timmer@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+package sqlite3
+
+import (
+	"crypto/sha1"
+	"crypto/sha256"
+	"crypto/sha512"
+)
+
+// This file provides several different implementations for the
+// default embedded sqlite_crypt function.
+// This function is uses a caesar-cypher by default
+// and is used within the UserAuthentication module to encode
+// the password.
+//
+// The provided functions can be used as an overload to the sqlite_crypt
+// function through the use of the RegisterFunc on the connection.
+//
+// Because the functions can serv a purpose to an end-user
+// without using the UserAuthentication module
+// the functions are default compiled in.
+//
+// From SQLITE3 - user-auth.txt
+// The sqlite_user.pw field is encoded by a built-in SQL function
+// "sqlite_crypt(X,Y)".  The two arguments are both BLOBs.  The first argument
+// is the plaintext password supplied to the sqlite3_user_authenticate()
+// interface.  The second argument is the sqlite_user.pw value and is supplied
+// so that the function can extract the "salt" used by the password encoder.
+// The result of sqlite_crypt(X,Y) is another blob which is the value that
+// ends up being stored in sqlite_user.pw.  To verify credentials X supplied
+// by the sqlite3_user_authenticate() routine, SQLite runs:
+//
+//     sqlite_user.pw == sqlite_crypt(X, sqlite_user.pw)
+//
+// To compute an appropriate sqlite_user.pw value from a new or modified
+// password X, sqlite_crypt(X,NULL) is run.  A new random salt is selected
+// when the second argument is NULL.
+//
+// The built-in version of of sqlite_crypt() uses a simple Caesar-cypher
+// which prevents passwords from being revealed by searching the raw database
+// for ASCII text, but is otherwise trivally broken.  For better password
+// security, the database should be encrypted using the SQLite Encryption
+// Extension or similar technology.  Or, the application can use the
+// sqlite3_create_function() interface to provide an alternative
+// implementation of sqlite_crypt() that computes a stronger password hash,
+// perhaps using a cryptographic hash function like SHA1.
+
+// CryptEncoderSHA1 encodes a password with SHA1
+func CryptEncoderSHA1(pass []byte, hash interface{}) []byte {
+	h := sha1.Sum(pass)
+	return h[:]
+}
+
+// CryptEncoderSSHA1 encodes a password with SHA1 with the
+// configured salt.
+func CryptEncoderSSHA1(salt string) func(pass []byte, hash interface{}) []byte {
+	return func(pass []byte, hash interface{}) []byte {
+		s := []byte(salt)
+		p := append(pass, s...)
+		h := sha1.Sum(p)
+		return h[:]
+	}
+}
+
+// CryptEncoderSHA256 encodes a password with SHA256
+func CryptEncoderSHA256(pass []byte, hash interface{}) []byte {
+	h := sha256.Sum256(pass)
+	return h[:]
+}
+
+// CryptEncoderSSHA256 encodes a password with SHA256
+// with the configured salt
+func CryptEncoderSSHA256(salt string) func(pass []byte, hash interface{}) []byte {
+	return func(pass []byte, hash interface{}) []byte {
+		s := []byte(salt)
+		p := append(pass, s...)
+		h := sha256.Sum256(p)
+		return h[:]
+	}
+}
+
+// CryptEncoderSHA384 encodes a password with SHA384
+func CryptEncoderSHA384(pass []byte, hash interface{}) []byte {
+	h := sha512.Sum384(pass)
+	return h[:]
+}
+
+// CryptEncoderSSHA384 encodes a password with SHA384
+// with the configured salt
+func CryptEncoderSSHA384(salt string) func(pass []byte, hash interface{}) []byte {
+	return func(pass []byte, hash interface{}) []byte {
+		s := []byte(salt)
+		p := append(pass, s...)
+		h := sha512.Sum384(p)
+		return h[:]
+	}
+}
+
+// CryptEncoderSHA512 encodes a password with SHA512
+func CryptEncoderSHA512(pass []byte, hash interface{}) []byte {
+	h := sha512.Sum512(pass)
+	return h[:]
+}
+
+// CryptEncoderSSHA512 encodes a password with SHA512
+// with the configured salt
+func CryptEncoderSSHA512(salt string) func(pass []byte, hash interface{}) []byte {
+	return func(pass []byte, hash interface{}) []byte {
+		s := []byte(salt)
+		p := append(pass, s...)
+		h := sha512.Sum512(p)
+		return h[:]
+	}
+}
+
+// EOF

vendor/github.com/mattn/go-sqlite3/sqlite3_go18.go

@@ -0,0 +1,70 @@
+// Copyright (C) 2019 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build cgo
+// +build go1.8
+
+package sqlite3
+
+import (
+	"database/sql/driver"
+
+	"context"
+)
+
+// Ping implement Pinger.
+func (c *SQLiteConn) Ping(ctx context.Context) error {
+	if c.db == nil {
+		// must be ErrBadConn for sql to close the database
+		return driver.ErrBadConn
+	}
+	return nil
+}
+
+// QueryContext implement QueryerContext.
+func (c *SQLiteConn) QueryContext(ctx context.Context, query string, args []driver.NamedValue) (driver.Rows, error) {
+	list := make([]namedValue, len(args))
+	for i, nv := range args {
+		list[i] = namedValue(nv)
+	}
+	return c.query(ctx, query, list)
+}
+
+// ExecContext implement ExecerContext.
+func (c *SQLiteConn) ExecContext(ctx context.Context, query string, args []driver.NamedValue) (driver.Result, error) {
+	list := make([]namedValue, len(args))
+	for i, nv := range args {
+		list[i] = namedValue(nv)
+	}
+	return c.exec(ctx, query, list)
+}
+
+// PrepareContext implement ConnPrepareContext.
+func (c *SQLiteConn) PrepareContext(ctx context.Context, query string) (driver.Stmt, error) {
+	return c.prepare(ctx, query)
+}
+
+// BeginTx implement ConnBeginTx.
+func (c *SQLiteConn) BeginTx(ctx context.Context, opts driver.TxOptions) (driver.Tx, error) {
+	return c.begin(ctx)
+}
+
+// QueryContext implement QueryerContext.
+func (s *SQLiteStmt) QueryContext(ctx context.Context, args []driver.NamedValue) (driver.Rows, error) {
+	list := make([]namedValue, len(args))
+	for i, nv := range args {
+		list[i] = namedValue(nv)
+	}
+	return s.query(ctx, list)
+}
+
+// ExecContext implement ExecerContext.
+func (s *SQLiteStmt) ExecContext(ctx context.Context, args []driver.NamedValue) (driver.Result, error) {
+	list := make([]namedValue, len(args))
+	for i, nv := range args {
+		list[i] = namedValue(nv)
+	}
+	return s.exec(ctx, list)
+}

vendor/github.com/mattn/go-sqlite3/sqlite3_libsqlite3.go

@@ -0,0 +1,19 @@
+// Copyright (C) 2019 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build libsqlite3
+
+package sqlite3
+
+/*
+#cgo CFLAGS: -DUSE_LIBSQLITE3
+#cgo linux LDFLAGS: -lsqlite3
+#cgo darwin LDFLAGS: -L/usr/local/opt/sqlite/lib -lsqlite3
+#cgo darwin CFLAGS: -I/usr/local/opt/sqlite/include
+#cgo openbsd LDFLAGS: -lsqlite3
+#cgo solaris LDFLAGS: -lsqlite3
+#cgo windows LDFLAGS: -lsqlite3
+*/
+import "C"

vendor/github.com/mattn/go-sqlite3/sqlite3_load_extension.go

@@ -0,0 +1,84 @@
+// Copyright (C) 2019 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build !sqlite_omit_load_extension
+
+package sqlite3
+
+/*
+#ifndef USE_LIBSQLITE3
+#include "sqlite3-binding.h"
+#else
+#include <sqlite3.h>
+#endif
+#include <stdlib.h>
+*/
+import "C"
+import (
+	"errors"
+	"unsafe"
+)
+
+func (c *SQLiteConn) loadExtensions(extensions []string) error {
+	rv := C.sqlite3_enable_load_extension(c.db, 1)
+	if rv != C.SQLITE_OK {
+		return errors.New(C.GoString(C.sqlite3_errmsg(c.db)))
+	}
+
+	for _, extension := range extensions {
+		if err := c.loadExtension(extension, nil); err != nil {
+			C.sqlite3_enable_load_extension(c.db, 0)
+			return err
+		}
+	}
+
+	rv = C.sqlite3_enable_load_extension(c.db, 0)
+	if rv != C.SQLITE_OK {
+		return errors.New(C.GoString(C.sqlite3_errmsg(c.db)))
+	}
+
+	return nil
+}
+
+// LoadExtension load the sqlite3 extension.
+func (c *SQLiteConn) LoadExtension(lib string, entry string) error {
+	rv := C.sqlite3_enable_load_extension(c.db, 1)
+	if rv != C.SQLITE_OK {
+		return errors.New(C.GoString(C.sqlite3_errmsg(c.db)))
+	}
+
+	if err := c.loadExtension(lib, &entry); err != nil {
+		C.sqlite3_enable_load_extension(c.db, 0)
+		return err
+	}
+
+	rv = C.sqlite3_enable_load_extension(c.db, 0)
+	if rv != C.SQLITE_OK {
+		return errors.New(C.GoString(C.sqlite3_errmsg(c.db)))
+	}
+
+	return nil
+}
+
+func (c *SQLiteConn) loadExtension(lib string, entry *string) error {
+	clib := C.CString(lib)
+	defer C.free(unsafe.Pointer(clib))
+
+	var centry *C.char
+	if entry != nil {
+		centry = C.CString(*entry)
+		defer C.free(unsafe.Pointer(centry))
+	}
+
+	var errMsg *C.char
+	defer C.sqlite3_free(unsafe.Pointer(errMsg))
+
+	rv := C.sqlite3_load_extension(c.db, clib, centry, &errMsg)
+	if rv != C.SQLITE_OK {
+		return errors.New(C.GoString(errMsg))
+	}
+
+	return nil
+}

vendor/github.com/mattn/go-sqlite3/sqlite3_load_extension_omit.go

@@ -0,0 +1,24 @@
+// Copyright (C) 2019 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build sqlite_omit_load_extension
+
+package sqlite3
+
+/*
+#cgo CFLAGS: -DSQLITE_OMIT_LOAD_EXTENSION
+*/
+import "C"
+import (
+	"errors"
+)
+
+func (c *SQLiteConn) loadExtensions(extensions []string) error {
+	return errors.New("Extensions have been disabled for static builds")
+}
+
+func (c *SQLiteConn) LoadExtension(lib string, entry string) error {
+	return errors.New("Extensions have been disabled for static builds")
+}

vendor/github.com/mattn/go-sqlite3/sqlite3_opt_allow_uri_authority.go

@@ -0,0 +1,15 @@
+// Copyright (C) 2019 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+// Copyright (C) 2018 G.J.R. Timmer <gjr.timmer@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build sqlite_allow_uri_authority
+
+package sqlite3
+
+/*
+#cgo CFLAGS: -DSQLITE_ALLOW_URI_AUTHORITY
+#cgo LDFLAGS: -lm
+*/
+import "C"

vendor/github.com/mattn/go-sqlite3/sqlite3_opt_app_armor.go

@@ -0,0 +1,16 @@
+// Copyright (C) 2019 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+// Copyright (C) 2018 G.J.R. Timmer <gjr.timmer@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build !windows
+// +build sqlite_app_armor
+
+package sqlite3
+
+/*
+#cgo CFLAGS: -DSQLITE_ENABLE_API_ARMOR
+#cgo LDFLAGS: -lm
+*/
+import "C"

vendor/github.com/mattn/go-sqlite3/sqlite3_opt_column_metadata.go

@@ -0,0 +1,21 @@
+// +build sqlite_column_metadata
+
+package sqlite3
+
+/*
+#ifndef USE_LIBSQLITE3
+#cgo CFLAGS: -DSQLITE_ENABLE_COLUMN_METADATA
+#include <sqlite3-binding.h>
+#else
+#include <sqlite3.h>
+#endif
+*/
+import "C"
+
+// ColumnTableName returns the table that is the origin of a particular result
+// column in a SELECT statement.
+//
+// See https://www.sqlite.org/c3ref/column_database_name.html
+func (s *SQLiteStmt) ColumnTableName(n int) string {
+	return C.GoString(C.sqlite3_column_table_name(s.s, C.int(n)))
+}

vendor/github.com/mattn/go-sqlite3/sqlite3_opt_foreign_keys.go

@@ -0,0 +1,15 @@
+// Copyright (C) 2019 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+// Copyright (C) 2018 G.J.R. Timmer <gjr.timmer@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build sqlite_foreign_keys
+
+package sqlite3
+
+/*
+#cgo CFLAGS: -DSQLITE_DEFAULT_FOREIGN_KEYS=1
+#cgo LDFLAGS: -lm
+*/
+import "C"

vendor/github.com/mattn/go-sqlite3/sqlite3_opt_fts5.go

@@ -0,0 +1,14 @@
+// Copyright (C) 2019 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build sqlite_fts5 fts5
+
+package sqlite3
+
+/*
+#cgo CFLAGS: -DSQLITE_ENABLE_FTS5
+#cgo LDFLAGS: -lm
+*/
+import "C"

vendor/github.com/mattn/go-sqlite3/sqlite3_opt_icu.go

@@ -0,0 +1,17 @@
+// Copyright (C) 2019 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build sqlite_icu icu
+
+package sqlite3
+
+/*
+#cgo LDFLAGS: -licuuc -licui18n
+#cgo CFLAGS: -DSQLITE_ENABLE_ICU
+#cgo darwin CFLAGS: -I/usr/local/opt/icu4c/include
+#cgo darwin LDFLAGS: -L/usr/local/opt/icu4c/lib
+#cgo openbsd LDFLAGS: -lsqlite3
+*/
+import "C"

vendor/github.com/mattn/go-sqlite3/sqlite3_opt_introspect.go

@@ -0,0 +1,15 @@
+// Copyright (C) 2019 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+// Copyright (C) 2018 G.J.R. Timmer <gjr.timmer@gmail.com>.
+
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build sqlite_introspect
+
+package sqlite3
+
+/*
+#cgo CFLAGS: -DSQLITE_INTROSPECTION_PRAGMAS
+#cgo LDFLAGS: -lm
+*/
+import "C"

vendor/github.com/mattn/go-sqlite3/sqlite3_opt_math_functions.go

@@ -0,0 +1,14 @@
+// Copyright (C) 2022 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build sqlite_math_functions
+
+package sqlite3
+
+/*
+#cgo CFLAGS: -DSQLITE_ENABLE_MATH_FUNCTIONS
+#cgo LDFLAGS: -lm
+*/
+import "C"

vendor/github.com/mattn/go-sqlite3/sqlite3_opt_os_trace.go

@@ -0,0 +1,15 @@
+// Copyright (C) 2022 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+//go:build sqlite_os_trace
+// +build sqlite_os_trace
+
+package sqlite3
+
+/*
+#cgo CFLAGS: -DSQLITE_FORCE_OS_TRACE=1
+#cgo CFLAGS: -DSQLITE_DEBUG_OS_TRACE=1
+*/
+import "C"

vendor/github.com/mattn/go-sqlite3/sqlite3_opt_preupdate.go

@@ -0,0 +1,20 @@
+// Copyright (C) 2019 G.J.R. Timmer <gjr.timmer@gmail.com>.
+// Copyright (C) 2018 segment.com <friends@segment.com>
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build cgo
+
+package sqlite3
+
+// SQLitePreUpdateData represents all of the data available during a
+// pre-update hook call.
+type SQLitePreUpdateData struct {
+	Conn         *SQLiteConn
+	Op           int
+	DatabaseName string
+	TableName    string
+	OldRowID     int64
+	NewRowID     int64
+}

vendor/github.com/mattn/go-sqlite3/sqlite3_opt_preupdate_hook.go

@@ -0,0 +1,112 @@
+// Copyright (C) 2019 G.J.R. Timmer <gjr.timmer@gmail.com>.
+// Copyright (C) 2018 segment.com <friends@segment.com>
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build sqlite_preupdate_hook
+
+package sqlite3
+
+/*
+#cgo CFLAGS: -DSQLITE_ENABLE_PREUPDATE_HOOK
+#cgo LDFLAGS: -lm
+
+#ifndef USE_LIBSQLITE3
+#include "sqlite3-binding.h"
+#else
+#include <sqlite3.h>
+#endif
+#include <stdlib.h>
+#include <string.h>
+
+void preUpdateHookTrampoline(void*, sqlite3 *, int, char *, char *, sqlite3_int64, sqlite3_int64);
+*/
+import "C"
+import (
+	"errors"
+	"unsafe"
+)
+
+// RegisterPreUpdateHook sets the pre-update hook for a connection.
+//
+// The callback is passed a SQLitePreUpdateData struct with the data for
+// the update, as well as methods for fetching copies of impacted data.
+//
+// If there is an existing preupdate hook for this connection, it will be
+// removed. If callback is nil the existing hook (if any) will be removed
+// without creating a new one.
+func (c *SQLiteConn) RegisterPreUpdateHook(callback func(SQLitePreUpdateData)) {
+	if callback == nil {
+		C.sqlite3_preupdate_hook(c.db, nil, nil)
+	} else {
+		C.sqlite3_preupdate_hook(c.db, (*[0]byte)(unsafe.Pointer(C.preUpdateHookTrampoline)), unsafe.Pointer(newHandle(c, callback)))
+	}
+}
+
+// Depth returns the source path of the write, see sqlite3_preupdate_depth()
+func (d *SQLitePreUpdateData) Depth() int {
+	return int(C.sqlite3_preupdate_depth(d.Conn.db))
+}
+
+// Count returns the number of columns in the row
+func (d *SQLitePreUpdateData) Count() int {
+	return int(C.sqlite3_preupdate_count(d.Conn.db))
+}
+
+func (d *SQLitePreUpdateData) row(dest []interface{}, new bool) error {
+	for i := 0; i < d.Count() && i < len(dest); i++ {
+		var val *C.sqlite3_value
+		var src interface{}
+
+		// Initially I tried making this just a function pointer argument, but
+		// it's absurdly complicated to pass C function pointers.
+		if new {
+			C.sqlite3_preupdate_new(d.Conn.db, C.int(i), &val)
+		} else {
+			C.sqlite3_preupdate_old(d.Conn.db, C.int(i), &val)
+		}
+
+		switch C.sqlite3_value_type(val) {
+		case C.SQLITE_INTEGER:
+			src = int64(C.sqlite3_value_int64(val))
+		case C.SQLITE_FLOAT:
+			src = float64(C.sqlite3_value_double(val))
+		case C.SQLITE_BLOB:
+			len := C.sqlite3_value_bytes(val)
+			blobptr := C.sqlite3_value_blob(val)
+			src = C.GoBytes(blobptr, len)
+		case C.SQLITE_TEXT:
+			len := C.sqlite3_value_bytes(val)
+			cstrptr := unsafe.Pointer(C.sqlite3_value_text(val))
+			src = C.GoBytes(cstrptr, len)
+		case C.SQLITE_NULL:
+			src = nil
+		}
+
+		err := convertAssign(&dest[i], src)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+// Old populates dest with the row data to be replaced. This works similar to
+// database/sql's Rows.Scan()
+func (d *SQLitePreUpdateData) Old(dest ...interface{}) error {
+	if d.Op == SQLITE_INSERT {
+		return errors.New("There is no old row for INSERT operations")
+	}
+	return d.row(dest, false)
+}
+
+// New populates dest with the replacement row data. This works similar to
+// database/sql's Rows.Scan()
+func (d *SQLitePreUpdateData) New(dest ...interface{}) error {
+	if d.Op == SQLITE_DELETE {
+		return errors.New("There is no new row for DELETE operations")
+	}
+	return d.row(dest, true)
+}

vendor/github.com/mattn/go-sqlite3/sqlite3_opt_preupdate_omit.go

@@ -0,0 +1,21 @@
+// Copyright (C) 2019 G.J.R. Timmer <gjr.timmer@gmail.com>.
+// Copyright (C) 2018 segment.com <friends@segment.com>
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build !sqlite_preupdate_hook,cgo
+
+package sqlite3
+
+// RegisterPreUpdateHook sets the pre-update hook for a connection.
+//
+// The callback is passed a SQLitePreUpdateData struct with the data for
+// the update, as well as methods for fetching copies of impacted data.
+//
+// If there is an existing preupdate hook for this connection, it will be
+// removed. If callback is nil the existing hook (if any) will be removed
+// without creating a new one.
+func (c *SQLiteConn) RegisterPreUpdateHook(callback func(SQLitePreUpdateData)) {
+	// NOOP
+}

vendor/github.com/mattn/go-sqlite3/sqlite3_opt_secure_delete.go

@@ -0,0 +1,15 @@
+// Copyright (C) 2019 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+// Copyright (C) 2018 G.J.R. Timmer <gjr.timmer@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build sqlite_secure_delete
+
+package sqlite3
+
+/*
+#cgo CFLAGS: -DSQLITE_SECURE_DELETE=1
+#cgo LDFLAGS: -lm
+*/
+import "C"

vendor/github.com/mattn/go-sqlite3/sqlite3_opt_secure_delete_fast.go

@@ -0,0 +1,15 @@
+// Copyright (C) 2019 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+// Copyright (C) 2018 G.J.R. Timmer <gjr.timmer@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build sqlite_secure_delete_fast
+
+package sqlite3
+
+/*
+#cgo CFLAGS: -DSQLITE_SECURE_DELETE=FAST
+#cgo LDFLAGS: -lm
+*/
+import "C"

vendor/github.com/mattn/go-sqlite3/sqlite3_opt_stat4.go

@@ -0,0 +1,15 @@
+// Copyright (C) 2019 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+// Copyright (C) 2018 G.J.R. Timmer <gjr.timmer@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build sqlite_stat4
+
+package sqlite3
+
+/*
+#cgo CFLAGS: -DSQLITE_ENABLE_STAT4
+#cgo LDFLAGS: -lm
+*/
+import "C"

vendor/github.com/mattn/go-sqlite3/sqlite3_opt_unlock_notify.c

@@ -0,0 +1,85 @@
+// Copyright (C) 2018 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+#ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
+#include <stdio.h>
+#include "sqlite3-binding.h"
+
+extern int unlock_notify_wait(sqlite3 *db);
+
+int
+_sqlite3_step_blocking(sqlite3_stmt *stmt)
+{
+  int rv;
+  sqlite3* db;
+
+  db = sqlite3_db_handle(stmt);
+  for (;;) {
+    rv = sqlite3_step(stmt);
+    if (rv != SQLITE_LOCKED) {
+      break;
+    }
+    if (sqlite3_extended_errcode(db) != SQLITE_LOCKED_SHAREDCACHE) {
+      break;
+    }
+    rv = unlock_notify_wait(db);
+    if (rv != SQLITE_OK) {
+      break;
+    }
+    sqlite3_reset(stmt);
+  }
+
+  return rv;
+}
+
+int
+_sqlite3_step_row_blocking(sqlite3_stmt* stmt, long long* rowid, long long* changes)
+{
+  int rv;
+  sqlite3* db;
+
+  db = sqlite3_db_handle(stmt);
+  for (;;) {
+    rv = sqlite3_step(stmt);
+    if (rv!=SQLITE_LOCKED) {
+      break;
+    }
+    if (sqlite3_extended_errcode(db) != SQLITE_LOCKED_SHAREDCACHE) {
+      break;
+    }
+    rv = unlock_notify_wait(db);
+    if (rv != SQLITE_OK) {
+      break;
+    }
+    sqlite3_reset(stmt);
+  }
+
+  *rowid = (long long) sqlite3_last_insert_rowid(db);
+  *changes = (long long) sqlite3_changes(db);
+  return rv;
+}
+
+int
+_sqlite3_prepare_v2_blocking(sqlite3 *db, const char *zSql, int nBytes, sqlite3_stmt **ppStmt, const char **pzTail)
+{
+  int rv;
+
+  for (;;) {
+    rv = sqlite3_prepare_v2(db, zSql, nBytes, ppStmt, pzTail);
+    if (rv!=SQLITE_LOCKED) {
+      break;
+    }
+    if (sqlite3_extended_errcode(db) != SQLITE_LOCKED_SHAREDCACHE) {
+      break;
+    }
+    rv = unlock_notify_wait(db);
+    if (rv != SQLITE_OK) {
+      break;
+    }
+  }
+
+  return rv;
+}
+#endif

vendor/github.com/mattn/go-sqlite3/sqlite3_opt_unlock_notify.go

@@ -0,0 +1,93 @@
+// Copyright (C) 2019 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build cgo
+// +build sqlite_unlock_notify
+
+package sqlite3
+
+/*
+#cgo CFLAGS: -DSQLITE_ENABLE_UNLOCK_NOTIFY
+
+#include <stdlib.h>
+#include "sqlite3-binding.h"
+
+extern void unlock_notify_callback(void *arg, int argc);
+*/
+import "C"
+import (
+	"fmt"
+	"math"
+	"sync"
+	"unsafe"
+)
+
+type unlock_notify_table struct {
+	sync.Mutex
+	seqnum uint
+	table  map[uint]chan struct{}
+}
+
+var unt unlock_notify_table = unlock_notify_table{table: make(map[uint]chan struct{})}
+
+func (t *unlock_notify_table) add(c chan struct{}) uint {
+	t.Lock()
+	defer t.Unlock()
+	h := t.seqnum
+	t.table[h] = c
+	t.seqnum++
+	return h
+}
+
+func (t *unlock_notify_table) remove(h uint) {
+	t.Lock()
+	defer t.Unlock()
+	delete(t.table, h)
+}
+
+func (t *unlock_notify_table) get(h uint) chan struct{} {
+	t.Lock()
+	defer t.Unlock()
+	c, ok := t.table[h]
+	if !ok {
+		panic(fmt.Sprintf("Non-existent key for unlcok-notify channel: %d", h))
+	}
+	return c
+}
+
+//export unlock_notify_callback
+func unlock_notify_callback(argv unsafe.Pointer, argc C.int) {
+	for i := 0; i < int(argc); i++ {
+		parg := ((*(*[(math.MaxInt32 - 1) / unsafe.Sizeof((*C.uint)(nil))]*[1]uint)(argv))[i])
+		arg := *parg
+		h := arg[0]
+		c := unt.get(h)
+		c <- struct{}{}
+	}
+}
+
+//export unlock_notify_wait
+func unlock_notify_wait(db *C.sqlite3) C.int {
+	// It has to be a bufferred channel to not block in sqlite_unlock_notify
+	// as sqlite_unlock_notify could invoke the callback before it returns.
+	c := make(chan struct{}, 1)
+	defer close(c)
+
+	h := unt.add(c)
+	defer unt.remove(h)
+
+	pargv := C.malloc(C.sizeof_uint)
+	defer C.free(pargv)
+
+	argv := (*[1]uint)(pargv)
+	argv[0] = h
+	if rv := C.sqlite3_unlock_notify(db, (*[0]byte)(C.unlock_notify_callback), unsafe.Pointer(pargv)); rv != C.SQLITE_OK {
+		return rv
+	}
+
+	<-c
+
+	return C.SQLITE_OK
+}

vendor/github.com/mattn/go-sqlite3/sqlite3_opt_userauth.go

@@ -0,0 +1,289 @@
+// Copyright (C) 2018 G.J.R. Timmer <gjr.timmer@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build sqlite_userauth
+
+package sqlite3
+
+/*
+#cgo CFLAGS: -DSQLITE_USER_AUTHENTICATION
+#cgo LDFLAGS: -lm
+#ifndef USE_LIBSQLITE3
+#include "sqlite3-binding.h"
+#else
+#include <sqlite3.h>
+#endif
+#include <stdlib.h>
+
+static int
+_sqlite3_user_authenticate(sqlite3* db, const char* zUsername, const char* aPW, int nPW)
+{
+  return sqlite3_user_authenticate(db, zUsername, aPW, nPW);
+}
+
+static int
+_sqlite3_user_add(sqlite3* db, const char* zUsername, const char* aPW, int nPW, int isAdmin)
+{
+  return sqlite3_user_add(db, zUsername, aPW, nPW, isAdmin);
+}
+
+static int
+_sqlite3_user_change(sqlite3* db, const char* zUsername, const char* aPW, int nPW, int isAdmin)
+{
+  return sqlite3_user_change(db, zUsername, aPW, nPW, isAdmin);
+}
+
+static int
+_sqlite3_user_delete(sqlite3* db, const char* zUsername)
+{
+  return sqlite3_user_delete(db, zUsername);
+}
+
+static int
+_sqlite3_auth_enabled(sqlite3* db)
+{
+	int exists = -1;
+
+	sqlite3_stmt *stmt;
+	sqlite3_prepare_v2(db, "select count(type) from sqlite_master WHERE type='table' and name='sqlite_user';", -1, &stmt, NULL);
+
+	while ( sqlite3_step(stmt) == SQLITE_ROW) {
+		exists = sqlite3_column_int(stmt, 0);
+	}
+
+	sqlite3_finalize(stmt);
+
+	return exists;
+}
+*/
+import "C"
+import (
+	"errors"
+	"unsafe"
+)
+
+const (
+	SQLITE_AUTH = C.SQLITE_AUTH
+)
+
+var (
+	ErrUnauthorized  = errors.New("SQLITE_AUTH: Unauthorized")
+	ErrAdminRequired = errors.New("SQLITE_AUTH: Unauthorized; Admin Privileges Required")
+)
+
+// Authenticate will perform an authentication of the provided username
+// and password against the database.
+//
+// If a database contains the SQLITE_USER table, then the
+// call to Authenticate must be invoked with an
+// appropriate username and password prior to enable read and write
+//access to the database.
+//
+// Return SQLITE_OK on success or SQLITE_ERROR if the username/password
+// combination is incorrect or unknown.
+//
+// If the SQLITE_USER table is not present in the database file, then
+// this interface is a harmless no-op returnning SQLITE_OK.
+func (c *SQLiteConn) Authenticate(username, password string) error {
+	rv := c.authenticate(username, password)
+	switch rv {
+	case C.SQLITE_ERROR, C.SQLITE_AUTH:
+		return ErrUnauthorized
+	case C.SQLITE_OK:
+		return nil
+	default:
+		return c.lastError()
+	}
+}
+
+// authenticate provides the actual authentication to SQLite.
+// This is not exported for usage in Go.
+// It is however exported for usage within SQL by the user.
+//
+// Returns:
+//	C.SQLITE_OK (0)
+//	C.SQLITE_ERROR (1)
+//  C.SQLITE_AUTH (23)
+func (c *SQLiteConn) authenticate(username, password string) int {
+	// Allocate C Variables
+	cuser := C.CString(username)
+	cpass := C.CString(password)
+
+	// Free C Variables
+	defer func() {
+		C.free(unsafe.Pointer(cuser))
+		C.free(unsafe.Pointer(cpass))
+	}()
+
+	return int(C._sqlite3_user_authenticate(c.db, cuser, cpass, C.int(len(password))))
+}
+
+// AuthUserAdd can be used (by an admin user only)
+// to create a new user. When called on a no-authentication-required
+// database, this routine converts the database into an authentication-
+// required database, automatically makes the added user an
+// administrator, and logs in the current connection as that user.
+// The AuthUserAdd only works for the "main" database, not
+// for any ATTACH-ed databases. Any call to AuthUserAdd by a
+// non-admin user results in an error.
+func (c *SQLiteConn) AuthUserAdd(username, password string, admin bool) error {
+	isAdmin := 0
+	if admin {
+		isAdmin = 1
+	}
+
+	rv := c.authUserAdd(username, password, isAdmin)
+	switch rv {
+	case C.SQLITE_ERROR, C.SQLITE_AUTH:
+		return ErrAdminRequired
+	case C.SQLITE_OK:
+		return nil
+	default:
+		return c.lastError()
+	}
+}
+
+// authUserAdd enables the User Authentication if not enabled.
+// Otherwise it will add a user.
+//
+// When user authentication is already enabled then this function
+// can only be called by an admin.
+//
+// This is not exported for usage in Go.
+// It is however exported for usage within SQL by the user.
+//
+// Returns:
+//	C.SQLITE_OK (0)
+//	C.SQLITE_ERROR (1)
+//  C.SQLITE_AUTH (23)
+func (c *SQLiteConn) authUserAdd(username, password string, admin int) int {
+	// Allocate C Variables
+	cuser := C.CString(username)
+	cpass := C.CString(password)
+
+	// Free C Variables
+	defer func() {
+		C.free(unsafe.Pointer(cuser))
+		C.free(unsafe.Pointer(cpass))
+	}()
+
+	return int(C._sqlite3_user_add(c.db, cuser, cpass, C.int(len(password)), C.int(admin)))
+}
+
+// AuthUserChange can be used to change a users
+// login credentials or admin privilege.  Any user can change their own
+// login credentials. Only an admin user can change another users login
+// credentials or admin privilege setting. No user may change their own
+// admin privilege setting.
+func (c *SQLiteConn) AuthUserChange(username, password string, admin bool) error {
+	isAdmin := 0
+	if admin {
+		isAdmin = 1
+	}
+
+	rv := c.authUserChange(username, password, isAdmin)
+	switch rv {
+	case C.SQLITE_ERROR, C.SQLITE_AUTH:
+		return ErrAdminRequired
+	case C.SQLITE_OK:
+		return nil
+	default:
+		return c.lastError()
+	}
+}
+
+// authUserChange allows to modify a user.
+// Users can change their own password.
+//
+// Only admins can change passwords for other users
+// and modify the admin flag.
+//
+// The admin flag of the current logged in user cannot be changed.
+// THis ensures that their is always an admin.
+//
+// This is not exported for usage in Go.
+// It is however exported for usage within SQL by the user.
+//
+// Returns:
+//	C.SQLITE_OK (0)
+//	C.SQLITE_ERROR (1)
+//  C.SQLITE_AUTH (23)
+func (c *SQLiteConn) authUserChange(username, password string, admin int) int {
+	// Allocate C Variables
+	cuser := C.CString(username)
+	cpass := C.CString(password)
+
+	// Free C Variables
+	defer func() {
+		C.free(unsafe.Pointer(cuser))
+		C.free(unsafe.Pointer(cpass))
+	}()
+
+	return int(C._sqlite3_user_change(c.db, cuser, cpass, C.int(len(password)), C.int(admin)))
+}
+
+// AuthUserDelete can be used (by an admin user only)
+// to delete a user. The currently logged-in user cannot be deleted,
+// which guarantees that there is always an admin user and hence that
+// the database cannot be converted into a no-authentication-required
+// database.
+func (c *SQLiteConn) AuthUserDelete(username string) error {
+	rv := c.authUserDelete(username)
+	switch rv {
+	case C.SQLITE_ERROR, C.SQLITE_AUTH:
+		return ErrAdminRequired
+	case C.SQLITE_OK:
+		return nil
+	default:
+		return c.lastError()
+	}
+}
+
+// authUserDelete can be used to delete a user.
+//
+// This function can only be executed by an admin.
+//
+// This is not exported for usage in Go.
+// It is however exported for usage within SQL by the user.
+//
+// Returns:
+//	C.SQLITE_OK (0)
+//	C.SQLITE_ERROR (1)
+//  C.SQLITE_AUTH (23)
+func (c *SQLiteConn) authUserDelete(username string) int {
+	// Allocate C Variables
+	cuser := C.CString(username)
+
+	// Free C Variables
+	defer func() {
+		C.free(unsafe.Pointer(cuser))
+	}()
+
+	return int(C._sqlite3_user_delete(c.db, cuser))
+}
+
+// AuthEnabled checks if the database is protected by user authentication
+func (c *SQLiteConn) AuthEnabled() (exists bool) {
+	rv := c.authEnabled()
+	if rv == 1 {
+		exists = true
+	}
+
+	return
+}
+
+// authEnabled perform the actual check for user authentication.
+//
+// This is not exported for usage in Go.
+// It is however exported for usage within SQL by the user.
+//
+// Returns:
+//	0 - Disabled
+//  1 - Enabled
+func (c *SQLiteConn) authEnabled() int {
+	return int(C._sqlite3_auth_enabled(c.db))
+}
+
+// EOF

vendor/github.com/mattn/go-sqlite3/sqlite3_opt_userauth_omit.go

@@ -0,0 +1,152 @@
+// Copyright (C) 2018 G.J.R. Timmer <gjr.timmer@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build !sqlite_userauth
+
+package sqlite3
+
+import (
+	"C"
+)
+
+// Authenticate will perform an authentication of the provided username
+// and password against the database.
+//
+// If a database contains the SQLITE_USER table, then the
+// call to Authenticate must be invoked with an
+// appropriate username and password prior to enable read and write
+//access to the database.
+//
+// Return SQLITE_OK on success or SQLITE_ERROR if the username/password
+// combination is incorrect or unknown.
+//
+// If the SQLITE_USER table is not present in the database file, then
+// this interface is a harmless no-op returnning SQLITE_OK.
+func (c *SQLiteConn) Authenticate(username, password string) error {
+	// NOOP
+	return nil
+}
+
+// authenticate provides the actual authentication to SQLite.
+// This is not exported for usage in Go.
+// It is however exported for usage within SQL by the user.
+//
+// Returns:
+//	C.SQLITE_OK (0)
+//	C.SQLITE_ERROR (1)
+//  C.SQLITE_AUTH (23)
+func (c *SQLiteConn) authenticate(username, password string) int {
+	// NOOP
+	return 0
+}
+
+// AuthUserAdd can be used (by an admin user only)
+// to create a new user.  When called on a no-authentication-required
+// database, this routine converts the database into an authentication-
+// required database, automatically makes the added user an
+// administrator, and logs in the current connection as that user.
+// The AuthUserAdd only works for the "main" database, not
+// for any ATTACH-ed databases. Any call to AuthUserAdd by a
+// non-admin user results in an error.
+func (c *SQLiteConn) AuthUserAdd(username, password string, admin bool) error {
+	// NOOP
+	return nil
+}
+
+// authUserAdd enables the User Authentication if not enabled.
+// Otherwise it will add a user.
+//
+// When user authentication is already enabled then this function
+// can only be called by an admin.
+//
+// This is not exported for usage in Go.
+// It is however exported for usage within SQL by the user.
+//
+// Returns:
+//	C.SQLITE_OK (0)
+//	C.SQLITE_ERROR (1)
+//  C.SQLITE_AUTH (23)
+func (c *SQLiteConn) authUserAdd(username, password string, admin int) int {
+	// NOOP
+	return 0
+}
+
+// AuthUserChange can be used to change a users
+// login credentials or admin privilege.  Any user can change their own
+// login credentials.  Only an admin user can change another users login
+// credentials or admin privilege setting.  No user may change their own
+// admin privilege setting.
+func (c *SQLiteConn) AuthUserChange(username, password string, admin bool) error {
+	// NOOP
+	return nil
+}
+
+// authUserChange allows to modify a user.
+// Users can change their own password.
+//
+// Only admins can change passwords for other users
+// and modify the admin flag.
+//
+// The admin flag of the current logged in user cannot be changed.
+// THis ensures that their is always an admin.
+//
+// This is not exported for usage in Go.
+// It is however exported for usage within SQL by the user.
+//
+// Returns:
+//	C.SQLITE_OK (0)
+//	C.SQLITE_ERROR (1)
+//  C.SQLITE_AUTH (23)
+func (c *SQLiteConn) authUserChange(username, password string, admin int) int {
+	// NOOP
+	return 0
+}
+
+// AuthUserDelete can be used (by an admin user only)
+// to delete a user.  The currently logged-in user cannot be deleted,
+// which guarantees that there is always an admin user and hence that
+// the database cannot be converted into a no-authentication-required
+// database.
+func (c *SQLiteConn) AuthUserDelete(username string) error {
+	// NOOP
+	return nil
+}
+
+// authUserDelete can be used to delete a user.
+//
+// This function can only be executed by an admin.
+//
+// This is not exported for usage in Go.
+// It is however exported for usage within SQL by the user.
+//
+// Returns:
+//	C.SQLITE_OK (0)
+//	C.SQLITE_ERROR (1)
+//  C.SQLITE_AUTH (23)
+func (c *SQLiteConn) authUserDelete(username string) int {
+	// NOOP
+	return 0
+}
+
+// AuthEnabled checks if the database is protected by user authentication
+func (c *SQLiteConn) AuthEnabled() (exists bool) {
+	// NOOP
+	return false
+}
+
+// authEnabled perform the actual check for user authentication.
+//
+// This is not exported for usage in Go.
+// It is however exported for usage within SQL by the user.
+//
+// Returns:
+//	0 - Disabled
+//  1 - Enabled
+func (c *SQLiteConn) authEnabled() int {
+	// NOOP
+	return 0
+}
+
+// EOF

vendor/github.com/mattn/go-sqlite3/sqlite3_opt_vacuum_full.go

@@ -0,0 +1,15 @@
+// Copyright (C) 2019 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+// Copyright (C) 2018 G.J.R. Timmer <gjr.timmer@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build sqlite_vacuum_full
+
+package sqlite3
+
+/*
+#cgo CFLAGS: -DSQLITE_DEFAULT_AUTOVACUUM=1
+#cgo LDFLAGS: -lm
+*/
+import "C"

vendor/github.com/mattn/go-sqlite3/sqlite3_opt_vacuum_incr.go

@@ -0,0 +1,15 @@
+// Copyright (C) 2019 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+// Copyright (C) 2018 G.J.R. Timmer <gjr.timmer@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build sqlite_vacuum_incr
+
+package sqlite3
+
+/*
+#cgo CFLAGS: -DSQLITE_DEFAULT_AUTOVACUUM=2
+#cgo LDFLAGS: -lm
+*/
+import "C"

vendor/github.com/mattn/go-sqlite3/sqlite3_opt_vtable.go

@@ -0,0 +1,720 @@
+// Copyright (C) 2019 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build sqlite_vtable vtable
+
+package sqlite3
+
+/*
+#cgo CFLAGS: -std=gnu99
+#cgo CFLAGS: -DSQLITE_ENABLE_RTREE
+#cgo CFLAGS: -DSQLITE_THREADSAFE
+#cgo CFLAGS: -DSQLITE_ENABLE_FTS3
+#cgo CFLAGS: -DSQLITE_ENABLE_FTS3_PARENTHESIS
+#cgo CFLAGS: -DSQLITE_ENABLE_FTS4_UNICODE61
+#cgo CFLAGS: -DSQLITE_TRACE_SIZE_LIMIT=15
+#cgo CFLAGS: -DSQLITE_ENABLE_COLUMN_METADATA=1
+#cgo CFLAGS: -Wno-deprecated-declarations
+
+#ifndef USE_LIBSQLITE3
+#include "sqlite3-binding.h"
+#else
+#include <sqlite3.h>
+#endif
+#include <stdlib.h>
+#include <stdint.h>
+#include <memory.h>
+
+static inline char *_sqlite3_mprintf(char *zFormat, char *arg) {
+  return sqlite3_mprintf(zFormat, arg);
+}
+
+typedef struct goVTab goVTab;
+
+struct goVTab {
+	sqlite3_vtab base;
+	void *vTab;
+};
+
+uintptr_t goMInit(void *db, void *pAux, int argc, char **argv, char **pzErr, int isCreate);
+
+static int cXInit(sqlite3 *db, void *pAux, int argc, const char *const*argv, sqlite3_vtab **ppVTab, char **pzErr, int isCreate) {
+	void *vTab = (void *)goMInit(db, pAux, argc, (char**)argv, pzErr, isCreate);
+	if (!vTab || *pzErr) {
+		return SQLITE_ERROR;
+	}
+	goVTab *pvTab = (goVTab *)sqlite3_malloc(sizeof(goVTab));
+	if (!pvTab) {
+		*pzErr = sqlite3_mprintf("%s", "Out of memory");
+		return SQLITE_NOMEM;
+	}
+	memset(pvTab, 0, sizeof(goVTab));
+	pvTab->vTab = vTab;
+
+	*ppVTab = (sqlite3_vtab *)pvTab;
+	*pzErr = 0;
+	return SQLITE_OK;
+}
+
+static inline int cXCreate(sqlite3 *db, void *pAux, int argc, const char *const*argv, sqlite3_vtab **ppVTab, char **pzErr) {
+	return cXInit(db, pAux, argc, argv, ppVTab, pzErr, 1);
+}
+static inline int cXConnect(sqlite3 *db, void *pAux, int argc, const char *const*argv, sqlite3_vtab **ppVTab, char **pzErr) {
+	return cXInit(db, pAux, argc, argv, ppVTab, pzErr, 0);
+}
+
+char* goVBestIndex(void *pVTab, void *icp);
+
+static inline int cXBestIndex(sqlite3_vtab *pVTab, sqlite3_index_info *info) {
+	char *pzErr = goVBestIndex(((goVTab*)pVTab)->vTab, info);
+	if (pzErr) {
+		if (pVTab->zErrMsg)
+			sqlite3_free(pVTab->zErrMsg);
+		pVTab->zErrMsg = pzErr;
+		return SQLITE_ERROR;
+	}
+	return SQLITE_OK;
+}
+
+char* goVRelease(void *pVTab, int isDestroy);
+
+static int cXRelease(sqlite3_vtab *pVTab, int isDestroy) {
+	char *pzErr = goVRelease(((goVTab*)pVTab)->vTab, isDestroy);
+	if (pzErr) {
+		if (pVTab->zErrMsg)
+			sqlite3_free(pVTab->zErrMsg);
+		pVTab->zErrMsg = pzErr;
+		return SQLITE_ERROR;
+	}
+	if (pVTab->zErrMsg)
+		sqlite3_free(pVTab->zErrMsg);
+	sqlite3_free(pVTab);
+	return SQLITE_OK;
+}
+
+static inline int cXDisconnect(sqlite3_vtab *pVTab) {
+	return cXRelease(pVTab, 0);
+}
+static inline int cXDestroy(sqlite3_vtab *pVTab) {
+	return cXRelease(pVTab, 1);
+}
+
+typedef struct goVTabCursor goVTabCursor;
+
+struct goVTabCursor {
+	sqlite3_vtab_cursor base;
+	void *vTabCursor;
+};
+
+uintptr_t goVOpen(void *pVTab, char **pzErr);
+
+static int cXOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor) {
+	void *vTabCursor = (void *)goVOpen(((goVTab*)pVTab)->vTab, &(pVTab->zErrMsg));
+	goVTabCursor *pCursor = (goVTabCursor *)sqlite3_malloc(sizeof(goVTabCursor));
+	if (!pCursor) {
+		return SQLITE_NOMEM;
+	}
+	memset(pCursor, 0, sizeof(goVTabCursor));
+	pCursor->vTabCursor = vTabCursor;
+	*ppCursor = (sqlite3_vtab_cursor *)pCursor;
+	return SQLITE_OK;
+}
+
+static int setErrMsg(sqlite3_vtab_cursor *pCursor, char *pzErr) {
+	if (pCursor->pVtab->zErrMsg)
+		sqlite3_free(pCursor->pVtab->zErrMsg);
+	pCursor->pVtab->zErrMsg = pzErr;
+	return SQLITE_ERROR;
+}
+
+char* goVClose(void *pCursor);
+
+static int cXClose(sqlite3_vtab_cursor *pCursor) {
+	char *pzErr = goVClose(((goVTabCursor*)pCursor)->vTabCursor);
+	if (pzErr) {
+		return setErrMsg(pCursor, pzErr);
+	}
+	sqlite3_free(pCursor);
+	return SQLITE_OK;
+}
+
+char* goVFilter(void *pCursor, int idxNum, char* idxName, int argc, sqlite3_value **argv);
+
+static int cXFilter(sqlite3_vtab_cursor *pCursor, int idxNum, const char *idxStr, int argc, sqlite3_value **argv) {
+	char *pzErr = goVFilter(((goVTabCursor*)pCursor)->vTabCursor, idxNum, (char*)idxStr, argc, argv);
+	if (pzErr) {
+		return setErrMsg(pCursor, pzErr);
+	}
+	return SQLITE_OK;
+}
+
+char* goVNext(void *pCursor);
+
+static int cXNext(sqlite3_vtab_cursor *pCursor) {
+	char *pzErr = goVNext(((goVTabCursor*)pCursor)->vTabCursor);
+	if (pzErr) {
+		return setErrMsg(pCursor, pzErr);
+	}
+	return SQLITE_OK;
+}
+
+int goVEof(void *pCursor);
+
+static inline int cXEof(sqlite3_vtab_cursor *pCursor) {
+	return goVEof(((goVTabCursor*)pCursor)->vTabCursor);
+}
+
+char* goVColumn(void *pCursor, void *cp, int col);
+
+static int cXColumn(sqlite3_vtab_cursor *pCursor, sqlite3_context *ctx, int i) {
+	char *pzErr = goVColumn(((goVTabCursor*)pCursor)->vTabCursor, ctx, i);
+	if (pzErr) {
+		return setErrMsg(pCursor, pzErr);
+	}
+	return SQLITE_OK;
+}
+
+char* goVRowid(void *pCursor, sqlite3_int64 *pRowid);
+
+static int cXRowid(sqlite3_vtab_cursor *pCursor, sqlite3_int64 *pRowid) {
+	char *pzErr = goVRowid(((goVTabCursor*)pCursor)->vTabCursor, pRowid);
+	if (pzErr) {
+		return setErrMsg(pCursor, pzErr);
+	}
+	return SQLITE_OK;
+}
+
+char* goVUpdate(void *pVTab, int argc, sqlite3_value **argv, sqlite3_int64 *pRowid);
+
+static int cXUpdate(sqlite3_vtab *pVTab, int argc, sqlite3_value **argv, sqlite3_int64 *pRowid) {
+	char *pzErr = goVUpdate(((goVTab*)pVTab)->vTab, argc, argv, pRowid);
+	if (pzErr) {
+		if (pVTab->zErrMsg)
+			sqlite3_free(pVTab->zErrMsg);
+		pVTab->zErrMsg = pzErr;
+		return SQLITE_ERROR;
+	}
+	return SQLITE_OK;
+}
+
+static sqlite3_module goModule = {
+	0,                       // iVersion
+	cXCreate,                // xCreate - create a table
+	cXConnect,               // xConnect - connect to an existing table
+	cXBestIndex,             // xBestIndex - Determine search strategy
+	cXDisconnect,            // xDisconnect - Disconnect from a table
+	cXDestroy,               // xDestroy - Drop a table
+	cXOpen,                  // xOpen - open a cursor
+	cXClose,                 // xClose - close a cursor
+	cXFilter,                // xFilter - configure scan constraints
+	cXNext,                  // xNext - advance a cursor
+	cXEof,                   // xEof
+	cXColumn,                // xColumn - read data
+	cXRowid,                 // xRowid - read data
+	cXUpdate,                // xUpdate - write data
+// Not implemented
+	0,                       // xBegin - begin transaction
+	0,                       // xSync - sync transaction
+	0,                       // xCommit - commit transaction
+	0,                       // xRollback - rollback transaction
+	0,                       // xFindFunction - function overloading
+	0,                       // xRename - rename the table
+	0,                       // xSavepoint
+	0,                       // xRelease
+	0	                     // xRollbackTo
+};
+
+// See https://sqlite.org/vtab.html#eponymous_only_virtual_tables
+static sqlite3_module goModuleEponymousOnly = {
+	0,                       // iVersion
+	0,                       // xCreate - create a table, which here is null
+	cXConnect,               // xConnect - connect to an existing table
+	cXBestIndex,             // xBestIndex - Determine search strategy
+	cXDisconnect,            // xDisconnect - Disconnect from a table
+	cXDestroy,               // xDestroy - Drop a table
+	cXOpen,                  // xOpen - open a cursor
+	cXClose,                 // xClose - close a cursor
+	cXFilter,                // xFilter - configure scan constraints
+	cXNext,                  // xNext - advance a cursor
+	cXEof,                   // xEof
+	cXColumn,                // xColumn - read data
+	cXRowid,                 // xRowid - read data
+	cXUpdate,                // xUpdate - write data
+// Not implemented
+	0,                       // xBegin - begin transaction
+	0,                       // xSync - sync transaction
+	0,                       // xCommit - commit transaction
+	0,                       // xRollback - rollback transaction
+	0,                       // xFindFunction - function overloading
+	0,                       // xRename - rename the table
+	0,                       // xSavepoint
+	0,                       // xRelease
+	0	                     // xRollbackTo
+};
+
+void goMDestroy(void*);
+
+static int _sqlite3_create_module(sqlite3 *db, const char *zName, uintptr_t pClientData) {
+  return sqlite3_create_module_v2(db, zName, &goModule, (void*) pClientData, goMDestroy);
+}
+
+static int _sqlite3_create_module_eponymous_only(sqlite3 *db, const char *zName, uintptr_t pClientData) {
+  return sqlite3_create_module_v2(db, zName, &goModuleEponymousOnly, (void*) pClientData, goMDestroy);
+}
+*/
+import "C"
+
+import (
+	"fmt"
+	"math"
+	"reflect"
+	"unsafe"
+)
+
+type sqliteModule struct {
+	c      *SQLiteConn
+	name   string
+	module Module
+}
+
+type sqliteVTab struct {
+	module *sqliteModule
+	vTab   VTab
+}
+
+type sqliteVTabCursor struct {
+	vTab       *sqliteVTab
+	vTabCursor VTabCursor
+}
+
+// Op is type of operations.
+type Op uint8
+
+// Op mean identity of operations.
+const (
+	OpEQ         Op = 2
+	OpGT            = 4
+	OpLE            = 8
+	OpLT            = 16
+	OpGE            = 32
+	OpMATCH         = 64
+	OpLIKE          = 65 /* 3.10.0 and later only */
+	OpGLOB          = 66 /* 3.10.0 and later only */
+	OpREGEXP        = 67 /* 3.10.0 and later only */
+	OpScanUnique    = 1  /* Scan visits at most 1 row */
+)
+
+// InfoConstraint give information of constraint.
+type InfoConstraint struct {
+	Column int
+	Op     Op
+	Usable bool
+}
+
+// InfoOrderBy give information of order-by.
+type InfoOrderBy struct {
+	Column int
+	Desc   bool
+}
+
+func constraints(info *C.sqlite3_index_info) []InfoConstraint {
+	slice := *(*[]C.struct_sqlite3_index_constraint)(unsafe.Pointer(&reflect.SliceHeader{
+		Data: uintptr(unsafe.Pointer(info.aConstraint)),
+		Len:  int(info.nConstraint),
+		Cap:  int(info.nConstraint),
+	}))
+
+	cst := make([]InfoConstraint, 0, len(slice))
+	for _, c := range slice {
+		var usable bool
+		if c.usable > 0 {
+			usable = true
+		}
+		cst = append(cst, InfoConstraint{
+			Column: int(c.iColumn),
+			Op:     Op(c.op),
+			Usable: usable,
+		})
+	}
+	return cst
+}
+
+func orderBys(info *C.sqlite3_index_info) []InfoOrderBy {
+	slice := *(*[]C.struct_sqlite3_index_orderby)(unsafe.Pointer(&reflect.SliceHeader{
+		Data: uintptr(unsafe.Pointer(info.aOrderBy)),
+		Len:  int(info.nOrderBy),
+		Cap:  int(info.nOrderBy),
+	}))
+
+	ob := make([]InfoOrderBy, 0, len(slice))
+	for _, c := range slice {
+		var desc bool
+		if c.desc > 0 {
+			desc = true
+		}
+		ob = append(ob, InfoOrderBy{
+			Column: int(c.iColumn),
+			Desc:   desc,
+		})
+	}
+	return ob
+}
+
+// IndexResult is a Go struct representation of what eventually ends up in the
+// output fields for `sqlite3_index_info`
+// See: https://www.sqlite.org/c3ref/index_info.html
+type IndexResult struct {
+	Used           []bool // aConstraintUsage
+	IdxNum         int
+	IdxStr         string
+	AlreadyOrdered bool // orderByConsumed
+	EstimatedCost  float64
+	EstimatedRows  float64
+}
+
+// mPrintf is a utility wrapper around sqlite3_mprintf
+func mPrintf(format, arg string) *C.char {
+	cf := C.CString(format)
+	defer C.free(unsafe.Pointer(cf))
+	ca := C.CString(arg)
+	defer C.free(unsafe.Pointer(ca))
+	return C._sqlite3_mprintf(cf, ca)
+}
+
+//export goMInit
+func goMInit(db, pClientData unsafe.Pointer, argc C.int, argv **C.char, pzErr **C.char, isCreate C.int) C.uintptr_t {
+	m := lookupHandle(pClientData).(*sqliteModule)
+	if m.c.db != (*C.sqlite3)(db) {
+		*pzErr = mPrintf("%s", "Inconsistent db handles")
+		return 0
+	}
+	args := make([]string, argc)
+	var A []*C.char
+	slice := reflect.SliceHeader{Data: uintptr(unsafe.Pointer(argv)), Len: int(argc), Cap: int(argc)}
+	a := reflect.NewAt(reflect.TypeOf(A), unsafe.Pointer(&slice)).Elem().Interface()
+	for i, s := range a.([]*C.char) {
+		args[i] = C.GoString(s)
+	}
+	var vTab VTab
+	var err error
+	if isCreate == 1 {
+		vTab, err = m.module.Create(m.c, args)
+	} else {
+		vTab, err = m.module.Connect(m.c, args)
+	}
+
+	if err != nil {
+		*pzErr = mPrintf("%s", err.Error())
+		return 0
+	}
+	vt := sqliteVTab{m, vTab}
+	*pzErr = nil
+	return C.uintptr_t(uintptr(newHandle(m.c, &vt)))
+}
+
+//export goVRelease
+func goVRelease(pVTab unsafe.Pointer, isDestroy C.int) *C.char {
+	vt := lookupHandle(pVTab).(*sqliteVTab)
+	var err error
+	if isDestroy == 1 {
+		err = vt.vTab.Destroy()
+	} else {
+		err = vt.vTab.Disconnect()
+	}
+	if err != nil {
+		return mPrintf("%s", err.Error())
+	}
+	return nil
+}
+
+//export goVOpen
+func goVOpen(pVTab unsafe.Pointer, pzErr **C.char) C.uintptr_t {
+	vt := lookupHandle(pVTab).(*sqliteVTab)
+	vTabCursor, err := vt.vTab.Open()
+	if err != nil {
+		*pzErr = mPrintf("%s", err.Error())
+		return 0
+	}
+	vtc := sqliteVTabCursor{vt, vTabCursor}
+	*pzErr = nil
+	return C.uintptr_t(uintptr(newHandle(vt.module.c, &vtc)))
+}
+
+//export goVBestIndex
+func goVBestIndex(pVTab unsafe.Pointer, icp unsafe.Pointer) *C.char {
+	vt := lookupHandle(pVTab).(*sqliteVTab)
+	info := (*C.sqlite3_index_info)(icp)
+	csts := constraints(info)
+	res, err := vt.vTab.BestIndex(csts, orderBys(info))
+	if err != nil {
+		return mPrintf("%s", err.Error())
+	}
+	if len(res.Used) != len(csts) {
+		return mPrintf("Result.Used != expected value", "")
+	}
+
+	// Get a pointer to constraint_usage struct so we can update in place.
+
+	slice := *(*[]C.struct_sqlite3_index_constraint_usage)(unsafe.Pointer(&reflect.SliceHeader{
+		Data: uintptr(unsafe.Pointer(info.aConstraintUsage)),
+		Len:  int(info.nConstraint),
+		Cap:  int(info.nConstraint),
+	}))
+	index := 1
+	for i := range slice {
+		if res.Used[i] {
+			slice[i].argvIndex = C.int(index)
+			slice[i].omit = C.uchar(1)
+			index++
+		}
+	}
+
+	info.idxNum = C.int(res.IdxNum)
+	info.idxStr = (*C.char)(C.sqlite3_malloc(C.int(len(res.IdxStr) + 1)))
+	if info.idxStr == nil {
+		// C.malloc and C.CString ordinarily do this for you. See https://golang.org/cmd/cgo/
+		panic("out of memory")
+	}
+	info.needToFreeIdxStr = C.int(1)
+
+	idxStr := *(*[]byte)(unsafe.Pointer(&reflect.SliceHeader{
+		Data: uintptr(unsafe.Pointer(info.idxStr)),
+		Len:  len(res.IdxStr) + 1,
+		Cap:  len(res.IdxStr) + 1,
+	}))
+	copy(idxStr, res.IdxStr)
+	idxStr[len(idxStr)-1] = 0 // null-terminated string
+
+	if res.AlreadyOrdered {
+		info.orderByConsumed = C.int(1)
+	}
+	info.estimatedCost = C.double(res.EstimatedCost)
+	info.estimatedRows = C.sqlite3_int64(res.EstimatedRows)
+
+	return nil
+}
+
+//export goVClose
+func goVClose(pCursor unsafe.Pointer) *C.char {
+	vtc := lookupHandle(pCursor).(*sqliteVTabCursor)
+	err := vtc.vTabCursor.Close()
+	if err != nil {
+		return mPrintf("%s", err.Error())
+	}
+	return nil
+}
+
+//export goMDestroy
+func goMDestroy(pClientData unsafe.Pointer) {
+	m := lookupHandle(pClientData).(*sqliteModule)
+	m.module.DestroyModule()
+}
+
+//export goVFilter
+func goVFilter(pCursor unsafe.Pointer, idxNum C.int, idxName *C.char, argc C.int, argv **C.sqlite3_value) *C.char {
+	vtc := lookupHandle(pCursor).(*sqliteVTabCursor)
+	args := (*[(math.MaxInt32 - 1) / unsafe.Sizeof((*C.sqlite3_value)(nil))]*C.sqlite3_value)(unsafe.Pointer(argv))[:argc:argc]
+	vals := make([]interface{}, 0, argc)
+	for _, v := range args {
+		conv, err := callbackArgGeneric(v)
+		if err != nil {
+			return mPrintf("%s", err.Error())
+		}
+		vals = append(vals, conv.Interface())
+	}
+	err := vtc.vTabCursor.Filter(int(idxNum), C.GoString(idxName), vals)
+	if err != nil {
+		return mPrintf("%s", err.Error())
+	}
+	return nil
+}
+
+//export goVNext
+func goVNext(pCursor unsafe.Pointer) *C.char {
+	vtc := lookupHandle(pCursor).(*sqliteVTabCursor)
+	err := vtc.vTabCursor.Next()
+	if err != nil {
+		return mPrintf("%s", err.Error())
+	}
+	return nil
+}
+
+//export goVEof
+func goVEof(pCursor unsafe.Pointer) C.int {
+	vtc := lookupHandle(pCursor).(*sqliteVTabCursor)
+	err := vtc.vTabCursor.EOF()
+	if err {
+		return 1
+	}
+	return 0
+}
+
+//export goVColumn
+func goVColumn(pCursor, cp unsafe.Pointer, col C.int) *C.char {
+	vtc := lookupHandle(pCursor).(*sqliteVTabCursor)
+	c := (*SQLiteContext)(cp)
+	err := vtc.vTabCursor.Column(c, int(col))
+	if err != nil {
+		return mPrintf("%s", err.Error())
+	}
+	return nil
+}
+
+//export goVRowid
+func goVRowid(pCursor unsafe.Pointer, pRowid *C.sqlite3_int64) *C.char {
+	vtc := lookupHandle(pCursor).(*sqliteVTabCursor)
+	rowid, err := vtc.vTabCursor.Rowid()
+	if err != nil {
+		return mPrintf("%s", err.Error())
+	}
+	*pRowid = C.sqlite3_int64(rowid)
+	return nil
+}
+
+//export goVUpdate
+func goVUpdate(pVTab unsafe.Pointer, argc C.int, argv **C.sqlite3_value, pRowid *C.sqlite3_int64) *C.char {
+	vt := lookupHandle(pVTab).(*sqliteVTab)
+
+	var tname string
+	if n, ok := vt.vTab.(interface {
+		TableName() string
+	}); ok {
+		tname = n.TableName() + " "
+	}
+
+	err := fmt.Errorf("virtual %s table %sis read-only", vt.module.name, tname)
+	if v, ok := vt.vTab.(VTabUpdater); ok {
+		// convert argv
+		args := (*[(math.MaxInt32 - 1) / unsafe.Sizeof((*C.sqlite3_value)(nil))]*C.sqlite3_value)(unsafe.Pointer(argv))[:argc:argc]
+		vals := make([]interface{}, 0, argc)
+		for _, v := range args {
+			conv, err := callbackArgGeneric(v)
+			if err != nil {
+				return mPrintf("%s", err.Error())
+			}
+
+			// work around for SQLITE_NULL
+			x := conv.Interface()
+			if z, ok := x.([]byte); ok && z == nil {
+				x = nil
+			}
+
+			vals = append(vals, x)
+		}
+
+		switch {
+		case argc == 1:
+			err = v.Delete(vals[0])
+
+		case argc > 1 && vals[0] == nil:
+			var id int64
+			id, err = v.Insert(vals[1], vals[2:])
+			if err == nil {
+				*pRowid = C.sqlite3_int64(id)
+			}
+
+		case argc > 1:
+			err = v.Update(vals[1], vals[2:])
+		}
+	}
+
+	if err != nil {
+		return mPrintf("%s", err.Error())
+	}
+
+	return nil
+}
+
+// Module is a "virtual table module", it defines the implementation of a
+// virtual tables. See: http://sqlite.org/c3ref/module.html
+type Module interface {
+	// http://sqlite.org/vtab.html#xcreate
+	Create(c *SQLiteConn, args []string) (VTab, error)
+	// http://sqlite.org/vtab.html#xconnect
+	Connect(c *SQLiteConn, args []string) (VTab, error)
+	// http://sqlite.org/c3ref/create_module.html
+	DestroyModule()
+}
+
+// EponymousOnlyModule is a "virtual table module" (as above), but
+// for defining "eponymous only" virtual tables See: https://sqlite.org/vtab.html#eponymous_only_virtual_tables
+type EponymousOnlyModule interface {
+	Module
+	EponymousOnlyModule()
+}
+
+// VTab describes a particular instance of the virtual table.
+// See: http://sqlite.org/c3ref/vtab.html
+type VTab interface {
+	// http://sqlite.org/vtab.html#xbestindex
+	BestIndex([]InfoConstraint, []InfoOrderBy) (*IndexResult, error)
+	// http://sqlite.org/vtab.html#xdisconnect
+	Disconnect() error
+	// http://sqlite.org/vtab.html#sqlite3_module.xDestroy
+	Destroy() error
+	// http://sqlite.org/vtab.html#xopen
+	Open() (VTabCursor, error)
+}
+
+// VTabUpdater is a type that allows a VTab to be inserted, updated, or
+// deleted.
+// See: https://sqlite.org/vtab.html#xupdate
+type VTabUpdater interface {
+	Delete(interface{}) error
+	Insert(interface{}, []interface{}) (int64, error)
+	Update(interface{}, []interface{}) error
+}
+
+// VTabCursor describes cursors that point into the virtual table and are used
+// to loop through the virtual table. See: http://sqlite.org/c3ref/vtab_cursor.html
+type VTabCursor interface {
+	// http://sqlite.org/vtab.html#xclose
+	Close() error
+	// http://sqlite.org/vtab.html#xfilter
+	Filter(idxNum int, idxStr string, vals []interface{}) error
+	// http://sqlite.org/vtab.html#xnext
+	Next() error
+	// http://sqlite.org/vtab.html#xeof
+	EOF() bool
+	// http://sqlite.org/vtab.html#xcolumn
+	Column(c *SQLiteContext, col int) error
+	// http://sqlite.org/vtab.html#xrowid
+	Rowid() (int64, error)
+}
+
+// DeclareVTab declares the Schema of a virtual table.
+// See: http://sqlite.org/c3ref/declare_vtab.html
+func (c *SQLiteConn) DeclareVTab(sql string) error {
+	zSQL := C.CString(sql)
+	defer C.free(unsafe.Pointer(zSQL))
+	rv := C.sqlite3_declare_vtab(c.db, zSQL)
+	if rv != C.SQLITE_OK {
+		return c.lastError()
+	}
+	return nil
+}
+
+// CreateModule registers a virtual table implementation.
+// See: http://sqlite.org/c3ref/create_module.html
+func (c *SQLiteConn) CreateModule(moduleName string, module Module) error {
+	mname := C.CString(moduleName)
+	defer C.free(unsafe.Pointer(mname))
+	udm := sqliteModule{c, moduleName, module}
+	switch module.(type) {
+	case EponymousOnlyModule:
+		rv := C._sqlite3_create_module_eponymous_only(c.db, mname, C.uintptr_t(uintptr(newHandle(c, &udm))))
+		if rv != C.SQLITE_OK {
+			return c.lastError()
+		}
+		return nil
+	case Module:
+		rv := C._sqlite3_create_module(c.db, mname, C.uintptr_t(uintptr(newHandle(c, &udm))))
+		if rv != C.SQLITE_OK {
+			return c.lastError()
+		}
+		return nil
+	}
+	return nil
+}

vendor/github.com/mattn/go-sqlite3/sqlite3_other.go

@@ -0,0 +1,17 @@
+// Copyright (C) 2019 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build !windows
+
+package sqlite3
+
+/*
+#cgo CFLAGS: -I.
+#cgo linux LDFLAGS: -ldl
+#cgo linux,ppc LDFLAGS: -lpthread
+#cgo linux,ppc64 LDFLAGS: -lpthread
+#cgo linux,ppc64le LDFLAGS: -lpthread
+*/
+import "C"

vendor/github.com/mattn/go-sqlite3/sqlite3_solaris.go

@@ -0,0 +1,14 @@
+// Copyright (C) 2019 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build solaris
+
+package sqlite3
+
+/*
+#cgo CFLAGS: -D__EXTENSIONS__=1
+#cgo LDFLAGS: -lc
+*/
+import "C"

vendor/github.com/mattn/go-sqlite3/sqlite3_trace.go

@@ -0,0 +1,287 @@
+// Copyright (C) 2019 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build sqlite_trace trace
+
+package sqlite3
+
+/*
+#ifndef USE_LIBSQLITE3
+#include "sqlite3-binding.h"
+#else
+#include <sqlite3.h>
+#endif
+#include <stdlib.h>
+
+int traceCallbackTrampoline(unsigned int traceEventCode, void *ctx, void *p, void *x);
+*/
+import "C"
+
+import (
+	"fmt"
+	"strings"
+	"sync"
+	"unsafe"
+)
+
+// Trace... constants identify the possible events causing callback invocation.
+// Values are same as the corresponding SQLite Trace Event Codes.
+const (
+	TraceStmt    = uint32(C.SQLITE_TRACE_STMT)
+	TraceProfile = uint32(C.SQLITE_TRACE_PROFILE)
+	TraceRow     = uint32(C.SQLITE_TRACE_ROW)
+	TraceClose   = uint32(C.SQLITE_TRACE_CLOSE)
+)
+
+type TraceInfo struct {
+	// Pack together the shorter fields, to keep the struct smaller.
+	// On a 64-bit machine there would be padding
+	// between EventCode and ConnHandle; having AutoCommit here is "free":
+	EventCode  uint32
+	AutoCommit bool
+	ConnHandle uintptr
+
+	// Usually filled, unless EventCode = TraceClose = SQLITE_TRACE_CLOSE:
+	// identifier for a prepared statement:
+	StmtHandle uintptr
+
+	// Two strings filled when EventCode = TraceStmt = SQLITE_TRACE_STMT:
+	// (1) either the unexpanded SQL text of the prepared statement, or
+	//     an SQL comment that indicates the invocation of a trigger;
+	// (2) expanded SQL, if requested and if (1) is not an SQL comment.
+	StmtOrTrigger string
+	ExpandedSQL   string // only if requested (TraceConfig.WantExpandedSQL = true)
+
+	// filled when EventCode = TraceProfile = SQLITE_TRACE_PROFILE:
+	// estimated number of nanoseconds that the prepared statement took to run:
+	RunTimeNanosec int64
+
+	DBError Error
+}
+
+// TraceUserCallback gives the signature for a trace function
+// provided by the user (Go application programmer).
+// SQLite 3.14 documentation (as of September 2, 2016)
+// for SQL Trace Hook = sqlite3_trace_v2():
+// The integer return value from the callback is currently ignored,
+// though this may change in future releases. Callback implementations
+// should return zero to ensure future compatibility.
+type TraceUserCallback func(TraceInfo) int
+
+type TraceConfig struct {
+	Callback        TraceUserCallback
+	EventMask       uint32
+	WantExpandedSQL bool
+}
+
+func fillDBError(dbErr *Error, db *C.sqlite3) {
+	// See SQLiteConn.lastError(), in file 'sqlite3.go' at the time of writing (Sept 5, 2016)
+	dbErr.Code = ErrNo(C.sqlite3_errcode(db))
+	dbErr.ExtendedCode = ErrNoExtended(C.sqlite3_extended_errcode(db))
+	dbErr.err = C.GoString(C.sqlite3_errmsg(db))
+}
+
+func fillExpandedSQL(info *TraceInfo, db *C.sqlite3, pStmt unsafe.Pointer) {
+	if pStmt == nil {
+		panic("No SQLite statement pointer in P arg of trace_v2 callback")
+	}
+
+	expSQLiteCStr := C.sqlite3_expanded_sql((*C.sqlite3_stmt)(pStmt))
+	defer C.sqlite3_free(unsafe.Pointer(expSQLiteCStr))
+	if expSQLiteCStr == nil {
+		fillDBError(&info.DBError, db)
+		return
+	}
+	info.ExpandedSQL = C.GoString(expSQLiteCStr)
+}
+
+//export traceCallbackTrampoline
+func traceCallbackTrampoline(
+	traceEventCode C.uint,
+	// Parameter named 'C' in SQLite docs = Context given at registration:
+	ctx unsafe.Pointer,
+	// Parameter named 'P' in SQLite docs (Primary event data?):
+	p unsafe.Pointer,
+	// Parameter named 'X' in SQLite docs (eXtra event data?):
+	xValue unsafe.Pointer) C.int {
+
+	eventCode := uint32(traceEventCode)
+
+	if ctx == nil {
+		panic(fmt.Sprintf("No context (ev 0x%x)", traceEventCode))
+	}
+
+	contextDB := (*C.sqlite3)(ctx)
+	connHandle := uintptr(ctx)
+
+	var traceConf TraceConfig
+	var found bool
+	if eventCode == TraceClose {
+		// clean up traceMap: 'pop' means get and delete
+		traceConf, found = popTraceMapping(connHandle)
+	} else {
+		traceConf, found = lookupTraceMapping(connHandle)
+	}
+
+	if !found {
+		panic(fmt.Sprintf("Mapping not found for handle 0x%x (ev 0x%x)",
+			connHandle, eventCode))
+	}
+
+	var info TraceInfo
+
+	info.EventCode = eventCode
+	info.AutoCommit = (int(C.sqlite3_get_autocommit(contextDB)) != 0)
+	info.ConnHandle = connHandle
+
+	switch eventCode {
+	case TraceStmt:
+		info.StmtHandle = uintptr(p)
+
+		var xStr string
+		if xValue != nil {
+			xStr = C.GoString((*C.char)(xValue))
+		}
+		info.StmtOrTrigger = xStr
+		if !strings.HasPrefix(xStr, "--") {
+			// Not SQL comment, therefore the current event
+			// is not related to a trigger.
+			// The user might want to receive the expanded SQL;
+			// let's check:
+			if traceConf.WantExpandedSQL {
+				fillExpandedSQL(&info, contextDB, p)
+			}
+		}
+
+	case TraceProfile:
+		info.StmtHandle = uintptr(p)
+
+		if xValue == nil {
+			panic("NULL pointer in X arg of trace_v2 callback for SQLITE_TRACE_PROFILE event")
+		}
+
+		info.RunTimeNanosec = *(*int64)(xValue)
+
+		// sample the error //TODO: is it safe? is it useful?
+		fillDBError(&info.DBError, contextDB)
+
+	case TraceRow:
+		info.StmtHandle = uintptr(p)
+
+	case TraceClose:
+		handle := uintptr(p)
+		if handle != info.ConnHandle {
+			panic(fmt.Sprintf("Different conn handle 0x%x (expected 0x%x) in SQLITE_TRACE_CLOSE event.",
+				handle, info.ConnHandle))
+		}
+
+	default:
+		// Pass unsupported events to the user callback (if configured);
+		// let the user callback decide whether to panic or ignore them.
+	}
+
+	// Do not execute user callback when the event was not requested by user!
+	// Remember that the Close event is always selected when
+	// registering this callback trampoline with SQLite --- for cleanup.
+	// In the future there may be more events forced to "selected" in SQLite
+	// for the driver's needs.
+	if traceConf.EventMask&eventCode == 0 {
+		return 0
+	}
+
+	r := 0
+	if traceConf.Callback != nil {
+		r = traceConf.Callback(info)
+	}
+	return C.int(r)
+}
+
+type traceMapEntry struct {
+	config TraceConfig
+}
+
+var traceMapLock sync.Mutex
+var traceMap = make(map[uintptr]traceMapEntry)
+
+func addTraceMapping(connHandle uintptr, traceConf TraceConfig) {
+	traceMapLock.Lock()
+	defer traceMapLock.Unlock()
+
+	oldEntryCopy, found := traceMap[connHandle]
+	if found {
+		panic(fmt.Sprintf("Adding trace config %v: handle 0x%x already registered (%v).",
+			traceConf, connHandle, oldEntryCopy.config))
+	}
+	traceMap[connHandle] = traceMapEntry{config: traceConf}
+}
+
+func lookupTraceMapping(connHandle uintptr) (TraceConfig, bool) {
+	traceMapLock.Lock()
+	defer traceMapLock.Unlock()
+
+	entryCopy, found := traceMap[connHandle]
+	return entryCopy.config, found
+}
+
+// 'pop' = get and delete from map before returning the value to the caller
+func popTraceMapping(connHandle uintptr) (TraceConfig, bool) {
+	traceMapLock.Lock()
+	defer traceMapLock.Unlock()
+
+	entryCopy, found := traceMap[connHandle]
+	if found {
+		delete(traceMap, connHandle)
+	}
+	return entryCopy.config, found
+}
+
+// SetTrace installs or removes the trace callback for the given database connection.
+// It's not named 'RegisterTrace' because only one callback can be kept and called.
+// Calling SetTrace a second time on same database connection
+// overrides (cancels) any prior callback and all its settings:
+// event mask, etc.
+func (c *SQLiteConn) SetTrace(requested *TraceConfig) error {
+	connHandle := uintptr(unsafe.Pointer(c.db))
+
+	_, _ = popTraceMapping(connHandle)
+
+	if requested == nil {
+		// The traceMap entry was deleted already by popTraceMapping():
+		// can disable all events now, no need to watch for TraceClose.
+		err := c.setSQLiteTrace(0)
+		return err
+	}
+
+	reqCopy := *requested
+
+	// Disable potentially expensive operations
+	// if their result will not be used. We are doing this
+	// just in case the caller provided nonsensical input.
+	if reqCopy.EventMask&TraceStmt == 0 {
+		reqCopy.WantExpandedSQL = false
+	}
+
+	addTraceMapping(connHandle, reqCopy)
+
+	// The callback trampoline function does cleanup on Close event,
+	// regardless of the presence or absence of the user callback.
+	// Therefore it needs the Close event to be selected:
+	actualEventMask := uint(reqCopy.EventMask | TraceClose)
+	err := c.setSQLiteTrace(actualEventMask)
+	return err
+}
+
+func (c *SQLiteConn) setSQLiteTrace(sqliteEventMask uint) error {
+	rv := C.sqlite3_trace_v2(c.db,
+		C.uint(sqliteEventMask),
+		(*[0]byte)(unsafe.Pointer(C.traceCallbackTrampoline)),
+		unsafe.Pointer(c.db)) // Fourth arg is same as first: we are
+	// passing the database connection handle as callback context.
+
+	if rv != C.SQLITE_OK {
+		return c.lastError()
+	}
+	return nil
+}

vendor/github.com/mattn/go-sqlite3/sqlite3_type.go

@@ -0,0 +1,108 @@
+// Copyright (C) 2019 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+package sqlite3
+
+/*
+#ifndef USE_LIBSQLITE3
+#include "sqlite3-binding.h"
+#else
+#include <sqlite3.h>
+#endif
+*/
+import "C"
+import (
+	"database/sql"
+	"reflect"
+	"strings"
+)
+
+// ColumnTypeDatabaseTypeName implement RowsColumnTypeDatabaseTypeName.
+func (rc *SQLiteRows) ColumnTypeDatabaseTypeName(i int) string {
+	return C.GoString(C.sqlite3_column_decltype(rc.s.s, C.int(i)))
+}
+
+/*
+func (rc *SQLiteRows) ColumnTypeLength(index int) (length int64, ok bool) {
+	return 0, false
+}
+
+func (rc *SQLiteRows) ColumnTypePrecisionScale(index int) (precision, scale int64, ok bool) {
+	return 0, 0, false
+}
+*/
+
+// ColumnTypeNullable implement RowsColumnTypeNullable.
+func (rc *SQLiteRows) ColumnTypeNullable(i int) (nullable, ok bool) {
+	return true, true
+}
+
+// ColumnTypeScanType implement RowsColumnTypeScanType.
+func (rc *SQLiteRows) ColumnTypeScanType(i int) reflect.Type {
+	//ct := C.sqlite3_column_type(rc.s.s, C.int(i))  // Always returns 5
+	return scanType(C.GoString(C.sqlite3_column_decltype(rc.s.s, C.int(i))))
+}
+
+const (
+	SQLITE_INTEGER = iota
+	SQLITE_TEXT
+	SQLITE_BLOB
+	SQLITE_REAL
+	SQLITE_NUMERIC
+	SQLITE_TIME
+	SQLITE_BOOL
+	SQLITE_NULL
+)
+
+func scanType(cdt string) reflect.Type {
+	t := strings.ToUpper(cdt)
+	i := databaseTypeConvSqlite(t)
+	switch i {
+	case SQLITE_INTEGER:
+		return reflect.TypeOf(sql.NullInt64{})
+	case SQLITE_TEXT:
+		return reflect.TypeOf(sql.NullString{})
+	case SQLITE_BLOB:
+		return reflect.TypeOf(sql.RawBytes{})
+	case SQLITE_REAL:
+		return reflect.TypeOf(sql.NullFloat64{})
+	case SQLITE_NUMERIC:
+		return reflect.TypeOf(sql.NullFloat64{})
+	case SQLITE_BOOL:
+		return reflect.TypeOf(sql.NullBool{})
+	case SQLITE_TIME:
+		return reflect.TypeOf(sql.NullTime{})
+	}
+	return reflect.TypeOf(new(interface{}))
+}
+
+func databaseTypeConvSqlite(t string) int {
+	if strings.Contains(t, "INT") {
+		return SQLITE_INTEGER
+	}
+	if t == "CLOB" || t == "TEXT" ||
+		strings.Contains(t, "CHAR") {
+		return SQLITE_TEXT
+	}
+	if t == "BLOB" {
+		return SQLITE_BLOB
+	}
+	if t == "REAL" || t == "FLOAT" ||
+		strings.Contains(t, "DOUBLE") {
+		return SQLITE_REAL
+	}
+	if t == "DATE" || t == "DATETIME" ||
+		t == "TIMESTAMP" {
+		return SQLITE_TIME
+	}
+	if t == "NUMERIC" ||
+		strings.Contains(t, "DECIMAL") {
+		return SQLITE_NUMERIC
+	}
+	if t == "BOOLEAN" {
+		return SQLITE_BOOL
+	}
+
+	return SQLITE_NULL
+}

vendor/github.com/mattn/go-sqlite3/sqlite3_usleep_windows.go

@@ -0,0 +1,41 @@
+// Copyright (C) 2018 G.J.R. Timmer <gjr.timmer@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build cgo
+
+package sqlite3
+
+// usleep is a function available on *nix based systems.
+// This function is not present in Windows.
+// Windows has a sleep function but this works with seconds
+// and not with microseconds as usleep.
+//
+// This code should improve performance on windows because
+// without the presence of usleep SQLite waits 1 second.
+//
+// Source:  https://github.com/php/php-src/blob/PHP-5.0/win32/time.c
+// License: https://github.com/php/php-src/blob/PHP-5.0/LICENSE
+// Details: https://stackoverflow.com/questions/5801813/c-usleep-is-obsolete-workarounds-for-windows-mingw?utm_medium=organic&utm_source=google_rich_qa&utm_campaign=google_rich_qa
+
+/*
+#include <windows.h>
+
+void usleep(__int64 usec)
+{
+    HANDLE timer;
+    LARGE_INTEGER ft;
+
+    // Convert to 100 nanosecond interval, negative value indicates relative time
+    ft.QuadPart = -(10*usec);
+
+    timer = CreateWaitableTimer(NULL, TRUE, NULL);
+    SetWaitableTimer(timer, &ft, 0, NULL, NULL, 0);
+    WaitForSingleObject(timer, INFINITE);
+    CloseHandle(timer);
+}
+*/
+import "C"
+
+// EOF

vendor/github.com/mattn/go-sqlite3/sqlite3_windows.go

@@ -0,0 +1,17 @@
+// Copyright (C) 2019 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build windows
+
+package sqlite3
+
+/*
+#cgo CFLAGS: -I.
+#cgo CFLAGS: -fno-stack-check
+#cgo CFLAGS: -fno-stack-protector
+#cgo CFLAGS: -mno-stack-arg-probe
+#cgo windows,386 CFLAGS: -D_USE_32BIT_TIME_T
+*/
+import "C"

vendor/github.com/mattn/go-sqlite3/sqlite3ext.h

@@ -0,0 +1,710 @@
+#ifndef USE_LIBSQLITE3
+/*
+** 2006 June 7
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This header file defines the SQLite interface for use by
+** shared libraries that want to be imported as extensions into
+** an SQLite instance.  Shared libraries that intend to be loaded
+** as extensions by SQLite should #include this file instead of 
+** sqlite3.h.
+*/
+#ifndef SQLITE3EXT_H
+#define SQLITE3EXT_H
+#include "sqlite3-binding.h"
+#ifdef __clang__
+#define assert(condition) ((void)0)
+#endif
+
+
+/*
+** The following structure holds pointers to all of the SQLite API
+** routines.
+**
+** WARNING:  In order to maintain backwards compatibility, add new
+** interfaces to the end of this structure only.  If you insert new
+** interfaces in the middle of this structure, then older different
+** versions of SQLite will not be able to load each other's shared
+** libraries!
+*/
+struct sqlite3_api_routines {
+  void * (*aggregate_context)(sqlite3_context*,int nBytes);
+  int  (*aggregate_count)(sqlite3_context*);
+  int  (*bind_blob)(sqlite3_stmt*,int,const void*,int n,void(*)(void*));
+  int  (*bind_double)(sqlite3_stmt*,int,double);
+  int  (*bind_int)(sqlite3_stmt*,int,int);
+  int  (*bind_int64)(sqlite3_stmt*,int,sqlite_int64);
+  int  (*bind_null)(sqlite3_stmt*,int);
+  int  (*bind_parameter_count)(sqlite3_stmt*);
+  int  (*bind_parameter_index)(sqlite3_stmt*,const char*zName);
+  const char * (*bind_parameter_name)(sqlite3_stmt*,int);
+  int  (*bind_text)(sqlite3_stmt*,int,const char*,int n,void(*)(void*));
+  int  (*bind_text16)(sqlite3_stmt*,int,const void*,int,void(*)(void*));
+  int  (*bind_value)(sqlite3_stmt*,int,const sqlite3_value*);
+  int  (*busy_handler)(sqlite3*,int(*)(void*,int),void*);
+  int  (*busy_timeout)(sqlite3*,int ms);
+  int  (*changes)(sqlite3*);
+  int  (*close)(sqlite3*);
+  int  (*collation_needed)(sqlite3*,void*,void(*)(void*,sqlite3*,
+                           int eTextRep,const char*));
+  int  (*collation_needed16)(sqlite3*,void*,void(*)(void*,sqlite3*,
+                             int eTextRep,const void*));
+  const void * (*column_blob)(sqlite3_stmt*,int iCol);
+  int  (*column_bytes)(sqlite3_stmt*,int iCol);
+  int  (*column_bytes16)(sqlite3_stmt*,int iCol);
+  int  (*column_count)(sqlite3_stmt*pStmt);
+  const char * (*column_database_name)(sqlite3_stmt*,int);
+  const void * (*column_database_name16)(sqlite3_stmt*,int);
+  const char * (*column_decltype)(sqlite3_stmt*,int i);
+  const void * (*column_decltype16)(sqlite3_stmt*,int);
+  double  (*column_double)(sqlite3_stmt*,int iCol);
+  int  (*column_int)(sqlite3_stmt*,int iCol);
+  sqlite_int64  (*column_int64)(sqlite3_stmt*,int iCol);
+  const char * (*column_name)(sqlite3_stmt*,int);
+  const void * (*column_name16)(sqlite3_stmt*,int);
+  const char * (*column_origin_name)(sqlite3_stmt*,int);
+  const void * (*column_origin_name16)(sqlite3_stmt*,int);
+  const char * (*column_table_name)(sqlite3_stmt*,int);
+  const void * (*column_table_name16)(sqlite3_stmt*,int);
+  const unsigned char * (*column_text)(sqlite3_stmt*,int iCol);
+  const void * (*column_text16)(sqlite3_stmt*,int iCol);
+  int  (*column_type)(sqlite3_stmt*,int iCol);
+  sqlite3_value* (*column_value)(sqlite3_stmt*,int iCol);
+  void * (*commit_hook)(sqlite3*,int(*)(void*),void*);
+  int  (*complete)(const char*sql);
+  int  (*complete16)(const void*sql);
+  int  (*create_collation)(sqlite3*,const char*,int,void*,
+                           int(*)(void*,int,const void*,int,const void*));
+  int  (*create_collation16)(sqlite3*,const void*,int,void*,
+                             int(*)(void*,int,const void*,int,const void*));
+  int  (*create_function)(sqlite3*,const char*,int,int,void*,
+                          void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
+                          void (*xStep)(sqlite3_context*,int,sqlite3_value**),
+                          void (*xFinal)(sqlite3_context*));
+  int  (*create_function16)(sqlite3*,const void*,int,int,void*,
+                            void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
+                            void (*xStep)(sqlite3_context*,int,sqlite3_value**),
+                            void (*xFinal)(sqlite3_context*));
+  int (*create_module)(sqlite3*,const char*,const sqlite3_module*,void*);
+  int  (*data_count)(sqlite3_stmt*pStmt);
+  sqlite3 * (*db_handle)(sqlite3_stmt*);
+  int (*declare_vtab)(sqlite3*,const char*);
+  int  (*enable_shared_cache)(int);
+  int  (*errcode)(sqlite3*db);
+  const char * (*errmsg)(sqlite3*);
+  const void * (*errmsg16)(sqlite3*);
+  int  (*exec)(sqlite3*,const char*,sqlite3_callback,void*,char**);
+  int  (*expired)(sqlite3_stmt*);
+  int  (*finalize)(sqlite3_stmt*pStmt);
+  void  (*free)(void*);
+  void  (*free_table)(char**result);
+  int  (*get_autocommit)(sqlite3*);
+  void * (*get_auxdata)(sqlite3_context*,int);
+  int  (*get_table)(sqlite3*,const char*,char***,int*,int*,char**);
+  int  (*global_recover)(void);
+  void  (*interruptx)(sqlite3*);
+  sqlite_int64  (*last_insert_rowid)(sqlite3*);
+  const char * (*libversion)(void);
+  int  (*libversion_number)(void);
+  void *(*malloc)(int);
+  char * (*mprintf)(const char*,...);
+  int  (*open)(const char*,sqlite3**);
+  int  (*open16)(const void*,sqlite3**);
+  int  (*prepare)(sqlite3*,const char*,int,sqlite3_stmt**,const char**);
+  int  (*prepare16)(sqlite3*,const void*,int,sqlite3_stmt**,const void**);
+  void * (*profile)(sqlite3*,void(*)(void*,const char*,sqlite_uint64),void*);
+  void  (*progress_handler)(sqlite3*,int,int(*)(void*),void*);
+  void *(*realloc)(void*,int);
+  int  (*reset)(sqlite3_stmt*pStmt);
+  void  (*result_blob)(sqlite3_context*,const void*,int,void(*)(void*));
+  void  (*result_double)(sqlite3_context*,double);
+  void  (*result_error)(sqlite3_context*,const char*,int);
+  void  (*result_error16)(sqlite3_context*,const void*,int);
+  void  (*result_int)(sqlite3_context*,int);
+  void  (*result_int64)(sqlite3_context*,sqlite_int64);
+  void  (*result_null)(sqlite3_context*);
+  void  (*result_text)(sqlite3_context*,const char*,int,void(*)(void*));
+  void  (*result_text16)(sqlite3_context*,const void*,int,void(*)(void*));
+  void  (*result_text16be)(sqlite3_context*,const void*,int,void(*)(void*));
+  void  (*result_text16le)(sqlite3_context*,const void*,int,void(*)(void*));
+  void  (*result_value)(sqlite3_context*,sqlite3_value*);
+  void * (*rollback_hook)(sqlite3*,void(*)(void*),void*);
+  int  (*set_authorizer)(sqlite3*,int(*)(void*,int,const char*,const char*,
+                         const char*,const char*),void*);
+  void  (*set_auxdata)(sqlite3_context*,int,void*,void (*)(void*));
+  char * (*xsnprintf)(int,char*,const char*,...);
+  int  (*step)(sqlite3_stmt*);
+  int  (*table_column_metadata)(sqlite3*,const char*,const char*,const char*,
+                                char const**,char const**,int*,int*,int*);
+  void  (*thread_cleanup)(void);
+  int  (*total_changes)(sqlite3*);
+  void * (*trace)(sqlite3*,void(*xTrace)(void*,const char*),void*);
+  int  (*transfer_bindings)(sqlite3_stmt*,sqlite3_stmt*);
+  void * (*update_hook)(sqlite3*,void(*)(void*,int ,char const*,char const*,
+                                         sqlite_int64),void*);
+  void * (*user_data)(sqlite3_context*);
+  const void * (*value_blob)(sqlite3_value*);
+  int  (*value_bytes)(sqlite3_value*);
+  int  (*value_bytes16)(sqlite3_value*);
+  double  (*value_double)(sqlite3_value*);
+  int  (*value_int)(sqlite3_value*);
+  sqlite_int64  (*value_int64)(sqlite3_value*);
+  int  (*value_numeric_type)(sqlite3_value*);
+  const unsigned char * (*value_text)(sqlite3_value*);
+  const void * (*value_text16)(sqlite3_value*);
+  const void * (*value_text16be)(sqlite3_value*);
+  const void * (*value_text16le)(sqlite3_value*);
+  int  (*value_type)(sqlite3_value*);
+  char *(*vmprintf)(const char*,va_list);
+  /* Added ??? */
+  int (*overload_function)(sqlite3*, const char *zFuncName, int nArg);
+  /* Added by 3.3.13 */
+  int (*prepare_v2)(sqlite3*,const char*,int,sqlite3_stmt**,const char**);
+  int (*prepare16_v2)(sqlite3*,const void*,int,sqlite3_stmt**,const void**);
+  int (*clear_bindings)(sqlite3_stmt*);
+  /* Added by 3.4.1 */
+  int (*create_module_v2)(sqlite3*,const char*,const sqlite3_module*,void*,
+                          void (*xDestroy)(void *));
+  /* Added by 3.5.0 */
+  int (*bind_zeroblob)(sqlite3_stmt*,int,int);
+  int (*blob_bytes)(sqlite3_blob*);
+  int (*blob_close)(sqlite3_blob*);
+  int (*blob_open)(sqlite3*,const char*,const char*,const char*,sqlite3_int64,
+                   int,sqlite3_blob**);
+  int (*blob_read)(sqlite3_blob*,void*,int,int);
+  int (*blob_write)(sqlite3_blob*,const void*,int,int);
+  int (*create_collation_v2)(sqlite3*,const char*,int,void*,
+                             int(*)(void*,int,const void*,int,const void*),
+                             void(*)(void*));
+  int (*file_control)(sqlite3*,const char*,int,void*);
+  sqlite3_int64 (*memory_highwater)(int);
+  sqlite3_int64 (*memory_used)(void);
+  sqlite3_mutex *(*mutex_alloc)(int);
+  void (*mutex_enter)(sqlite3_mutex*);
+  void (*mutex_free)(sqlite3_mutex*);
+  void (*mutex_leave)(sqlite3_mutex*);
+  int (*mutex_try)(sqlite3_mutex*);
+  int (*open_v2)(const char*,sqlite3**,int,const char*);
+  int (*release_memory)(int);
+  void (*result_error_nomem)(sqlite3_context*);
+  void (*result_error_toobig)(sqlite3_context*);
+  int (*sleep)(int);
+  void (*soft_heap_limit)(int);
+  sqlite3_vfs *(*vfs_find)(const char*);
+  int (*vfs_register)(sqlite3_vfs*,int);
+  int (*vfs_unregister)(sqlite3_vfs*);
+  int (*xthreadsafe)(void);
+  void (*result_zeroblob)(sqlite3_context*,int);
+  void (*result_error_code)(sqlite3_context*,int);
+  int (*test_control)(int, ...);
+  void (*randomness)(int,void*);
+  sqlite3 *(*context_db_handle)(sqlite3_context*);
+  int (*extended_result_codes)(sqlite3*,int);
+  int (*limit)(sqlite3*,int,int);
+  sqlite3_stmt *(*next_stmt)(sqlite3*,sqlite3_stmt*);
+  const char *(*sql)(sqlite3_stmt*);
+  int (*status)(int,int*,int*,int);
+  int (*backup_finish)(sqlite3_backup*);
+  sqlite3_backup *(*backup_init)(sqlite3*,const char*,sqlite3*,const char*);
+  int (*backup_pagecount)(sqlite3_backup*);
+  int (*backup_remaining)(sqlite3_backup*);
+  int (*backup_step)(sqlite3_backup*,int);
+  const char *(*compileoption_get)(int);
+  int (*compileoption_used)(const char*);
+  int (*create_function_v2)(sqlite3*,const char*,int,int,void*,
+                            void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
+                            void (*xStep)(sqlite3_context*,int,sqlite3_value**),
+                            void (*xFinal)(sqlite3_context*),
+                            void(*xDestroy)(void*));
+  int (*db_config)(sqlite3*,int,...);
+  sqlite3_mutex *(*db_mutex)(sqlite3*);
+  int (*db_status)(sqlite3*,int,int*,int*,int);
+  int (*extended_errcode)(sqlite3*);
+  void (*log)(int,const char*,...);
+  sqlite3_int64 (*soft_heap_limit64)(sqlite3_int64);
+  const char *(*sourceid)(void);
+  int (*stmt_status)(sqlite3_stmt*,int,int);
+  int (*strnicmp)(const char*,const char*,int);
+  int (*unlock_notify)(sqlite3*,void(*)(void**,int),void*);
+  int (*wal_autocheckpoint)(sqlite3*,int);
+  int (*wal_checkpoint)(sqlite3*,const char*);
+  void *(*wal_hook)(sqlite3*,int(*)(void*,sqlite3*,const char*,int),void*);
+  int (*blob_reopen)(sqlite3_blob*,sqlite3_int64);
+  int (*vtab_config)(sqlite3*,int op,...);
+  int (*vtab_on_conflict)(sqlite3*);
+  /* Version 3.7.16 and later */
+  int (*close_v2)(sqlite3*);
+  const char *(*db_filename)(sqlite3*,const char*);
+  int (*db_readonly)(sqlite3*,const char*);
+  int (*db_release_memory)(sqlite3*);
+  const char *(*errstr)(int);
+  int (*stmt_busy)(sqlite3_stmt*);
+  int (*stmt_readonly)(sqlite3_stmt*);
+  int (*stricmp)(const char*,const char*);
+  int (*uri_boolean)(const char*,const char*,int);
+  sqlite3_int64 (*uri_int64)(const char*,const char*,sqlite3_int64);
+  const char *(*uri_parameter)(const char*,const char*);
+  char *(*xvsnprintf)(int,char*,const char*,va_list);
+  int (*wal_checkpoint_v2)(sqlite3*,const char*,int,int*,int*);
+  /* Version 3.8.7 and later */
+  int (*auto_extension)(void(*)(void));
+  int (*bind_blob64)(sqlite3_stmt*,int,const void*,sqlite3_uint64,
+                     void(*)(void*));
+  int (*bind_text64)(sqlite3_stmt*,int,const char*,sqlite3_uint64,
+                      void(*)(void*),unsigned char);
+  int (*cancel_auto_extension)(void(*)(void));
+  int (*load_extension)(sqlite3*,const char*,const char*,char**);
+  void *(*malloc64)(sqlite3_uint64);
+  sqlite3_uint64 (*msize)(void*);
+  void *(*realloc64)(void*,sqlite3_uint64);
+  void (*reset_auto_extension)(void);
+  void (*result_blob64)(sqlite3_context*,const void*,sqlite3_uint64,
+                        void(*)(void*));
+  void (*result_text64)(sqlite3_context*,const char*,sqlite3_uint64,
+                         void(*)(void*), unsigned char);
+  int (*strglob)(const char*,const char*);
+  /* Version 3.8.11 and later */
+  sqlite3_value *(*value_dup)(const sqlite3_value*);
+  void (*value_free)(sqlite3_value*);
+  int (*result_zeroblob64)(sqlite3_context*,sqlite3_uint64);
+  int (*bind_zeroblob64)(sqlite3_stmt*, int, sqlite3_uint64);
+  /* Version 3.9.0 and later */
+  unsigned int (*value_subtype)(sqlite3_value*);
+  void (*result_subtype)(sqlite3_context*,unsigned int);
+  /* Version 3.10.0 and later */
+  int (*status64)(int,sqlite3_int64*,sqlite3_int64*,int);
+  int (*strlike)(const char*,const char*,unsigned int);
+  int (*db_cacheflush)(sqlite3*);
+  /* Version 3.12.0 and later */
+  int (*system_errno)(sqlite3*);
+  /* Version 3.14.0 and later */
+  int (*trace_v2)(sqlite3*,unsigned,int(*)(unsigned,void*,void*,void*),void*);
+  char *(*expanded_sql)(sqlite3_stmt*);
+  /* Version 3.18.0 and later */
+  void (*set_last_insert_rowid)(sqlite3*,sqlite3_int64);
+  /* Version 3.20.0 and later */
+  int (*prepare_v3)(sqlite3*,const char*,int,unsigned int,
+                    sqlite3_stmt**,const char**);
+  int (*prepare16_v3)(sqlite3*,const void*,int,unsigned int,
+                      sqlite3_stmt**,const void**);
+  int (*bind_pointer)(sqlite3_stmt*,int,void*,const char*,void(*)(void*));
+  void (*result_pointer)(sqlite3_context*,void*,const char*,void(*)(void*));
+  void *(*value_pointer)(sqlite3_value*,const char*);
+  int (*vtab_nochange)(sqlite3_context*);
+  int (*value_nochange)(sqlite3_value*);
+  const char *(*vtab_collation)(sqlite3_index_info*,int);
+  /* Version 3.24.0 and later */
+  int (*keyword_count)(void);
+  int (*keyword_name)(int,const char**,int*);
+  int (*keyword_check)(const char*,int);
+  sqlite3_str *(*str_new)(sqlite3*);
+  char *(*str_finish)(sqlite3_str*);
+  void (*str_appendf)(sqlite3_str*, const char *zFormat, ...);
+  void (*str_vappendf)(sqlite3_str*, const char *zFormat, va_list);
+  void (*str_append)(sqlite3_str*, const char *zIn, int N);
+  void (*str_appendall)(sqlite3_str*, const char *zIn);
+  void (*str_appendchar)(sqlite3_str*, int N, char C);
+  void (*str_reset)(sqlite3_str*);
+  int (*str_errcode)(sqlite3_str*);
+  int (*str_length)(sqlite3_str*);
+  char *(*str_value)(sqlite3_str*);
+  /* Version 3.25.0 and later */
+  int (*create_window_function)(sqlite3*,const char*,int,int,void*,
+                            void (*xStep)(sqlite3_context*,int,sqlite3_value**),
+                            void (*xFinal)(sqlite3_context*),
+                            void (*xValue)(sqlite3_context*),
+                            void (*xInv)(sqlite3_context*,int,sqlite3_value**),
+                            void(*xDestroy)(void*));
+  /* Version 3.26.0 and later */
+  const char *(*normalized_sql)(sqlite3_stmt*);
+  /* Version 3.28.0 and later */
+  int (*stmt_isexplain)(sqlite3_stmt*);
+  int (*value_frombind)(sqlite3_value*);
+  /* Version 3.30.0 and later */
+  int (*drop_modules)(sqlite3*,const char**);
+  /* Version 3.31.0 and later */
+  sqlite3_int64 (*hard_heap_limit64)(sqlite3_int64);
+  const char *(*uri_key)(const char*,int);
+  const char *(*filename_database)(const char*);
+  const char *(*filename_journal)(const char*);
+  const char *(*filename_wal)(const char*);
+  /* Version 3.32.0 and later */
+  char *(*create_filename)(const char*,const char*,const char*,
+                           int,const char**);
+  void (*free_filename)(char*);
+  sqlite3_file *(*database_file_object)(const char*);
+  /* Version 3.34.0 and later */
+  int (*txn_state)(sqlite3*,const char*);
+  /* Version 3.36.1 and later */
+  sqlite3_int64 (*changes64)(sqlite3*);
+  sqlite3_int64 (*total_changes64)(sqlite3*);
+  /* Version 3.37.0 and later */
+  int (*autovacuum_pages)(sqlite3*,
+     unsigned int(*)(void*,const char*,unsigned int,unsigned int,unsigned int),
+     void*, void(*)(void*));
+  /* Version 3.38.0 and later */
+  int (*error_offset)(sqlite3*);
+  int (*vtab_rhs_value)(sqlite3_index_info*,int,sqlite3_value**);
+  int (*vtab_distinct)(sqlite3_index_info*);
+  int (*vtab_in)(sqlite3_index_info*,int,int);
+  int (*vtab_in_first)(sqlite3_value*,sqlite3_value**);
+  int (*vtab_in_next)(sqlite3_value*,sqlite3_value**);
+  /* Version 3.39.0 and later */
+  int (*deserialize)(sqlite3*,const char*,unsigned char*,
+                     sqlite3_int64,sqlite3_int64,unsigned);
+  unsigned char *(*serialize)(sqlite3*,const char *,sqlite3_int64*,
+                              unsigned int);
+  const char *(*db_name)(sqlite3*,int);
+};
+
+/*
+** This is the function signature used for all extension entry points.  It
+** is also defined in the file "loadext.c".
+*/
+typedef int (*sqlite3_loadext_entry)(
+  sqlite3 *db,                       /* Handle to the database. */
+  char **pzErrMsg,                   /* Used to set error string on failure. */
+  const sqlite3_api_routines *pThunk /* Extension API function pointers. */
+);
+
+/*
+** The following macros redefine the API routines so that they are
+** redirected through the global sqlite3_api structure.
+**
+** This header file is also used by the loadext.c source file
+** (part of the main SQLite library - not an extension) so that
+** it can get access to the sqlite3_api_routines structure
+** definition.  But the main library does not want to redefine
+** the API.  So the redefinition macros are only valid if the
+** SQLITE_CORE macros is undefined.
+*/
+#if !defined(SQLITE_CORE) && !defined(SQLITE_OMIT_LOAD_EXTENSION)
+#define sqlite3_aggregate_context      sqlite3_api->aggregate_context
+#ifndef SQLITE_OMIT_DEPRECATED
+#define sqlite3_aggregate_count        sqlite3_api->aggregate_count
+#endif
+#define sqlite3_bind_blob              sqlite3_api->bind_blob
+#define sqlite3_bind_double            sqlite3_api->bind_double
+#define sqlite3_bind_int               sqlite3_api->bind_int
+#define sqlite3_bind_int64             sqlite3_api->bind_int64
+#define sqlite3_bind_null              sqlite3_api->bind_null
+#define sqlite3_bind_parameter_count   sqlite3_api->bind_parameter_count
+#define sqlite3_bind_parameter_index   sqlite3_api->bind_parameter_index
+#define sqlite3_bind_parameter_name    sqlite3_api->bind_parameter_name
+#define sqlite3_bind_text              sqlite3_api->bind_text
+#define sqlite3_bind_text16            sqlite3_api->bind_text16
+#define sqlite3_bind_value             sqlite3_api->bind_value
+#define sqlite3_busy_handler           sqlite3_api->busy_handler
+#define sqlite3_busy_timeout           sqlite3_api->busy_timeout
+#define sqlite3_changes                sqlite3_api->changes
+#define sqlite3_close                  sqlite3_api->close
+#define sqlite3_collation_needed       sqlite3_api->collation_needed
+#define sqlite3_collation_needed16     sqlite3_api->collation_needed16
+#define sqlite3_column_blob            sqlite3_api->column_blob
+#define sqlite3_column_bytes           sqlite3_api->column_bytes
+#define sqlite3_column_bytes16         sqlite3_api->column_bytes16
+#define sqlite3_column_count           sqlite3_api->column_count
+#define sqlite3_column_database_name   sqlite3_api->column_database_name
+#define sqlite3_column_database_name16 sqlite3_api->column_database_name16
+#define sqlite3_column_decltype        sqlite3_api->column_decltype
+#define sqlite3_column_decltype16      sqlite3_api->column_decltype16
+#define sqlite3_column_double          sqlite3_api->column_double
+#define sqlite3_column_int             sqlite3_api->column_int
+#define sqlite3_column_int64           sqlite3_api->column_int64
+#define sqlite3_column_name            sqlite3_api->column_name
+#define sqlite3_column_name16          sqlite3_api->column_name16
+#define sqlite3_column_origin_name     sqlite3_api->column_origin_name
+#define sqlite3_column_origin_name16   sqlite3_api->column_origin_name16
+#define sqlite3_column_table_name      sqlite3_api->column_table_name
+#define sqlite3_column_table_name16    sqlite3_api->column_table_name16
+#define sqlite3_column_text            sqlite3_api->column_text
+#define sqlite3_column_text16          sqlite3_api->column_text16
+#define sqlite3_column_type            sqlite3_api->column_type
+#define sqlite3_column_value           sqlite3_api->column_value
+#define sqlite3_commit_hook            sqlite3_api->commit_hook
+#define sqlite3_complete               sqlite3_api->complete
+#define sqlite3_complete16             sqlite3_api->complete16
+#define sqlite3_create_collation       sqlite3_api->create_collation
+#define sqlite3_create_collation16     sqlite3_api->create_collation16
+#define sqlite3_create_function        sqlite3_api->create_function
+#define sqlite3_create_function16      sqlite3_api->create_function16
+#define sqlite3_create_module          sqlite3_api->create_module
+#define sqlite3_create_module_v2       sqlite3_api->create_module_v2
+#define sqlite3_data_count             sqlite3_api->data_count
+#define sqlite3_db_handle              sqlite3_api->db_handle
+#define sqlite3_declare_vtab           sqlite3_api->declare_vtab
+#define sqlite3_enable_shared_cache    sqlite3_api->enable_shared_cache
+#define sqlite3_errcode                sqlite3_api->errcode
+#define sqlite3_errmsg                 sqlite3_api->errmsg
+#define sqlite3_errmsg16               sqlite3_api->errmsg16
+#define sqlite3_exec                   sqlite3_api->exec
+#ifndef SQLITE_OMIT_DEPRECATED
+#define sqlite3_expired                sqlite3_api->expired
+#endif
+#define sqlite3_finalize               sqlite3_api->finalize
+#define sqlite3_free                   sqlite3_api->free
+#define sqlite3_free_table             sqlite3_api->free_table
+#define sqlite3_get_autocommit         sqlite3_api->get_autocommit
+#define sqlite3_get_auxdata            sqlite3_api->get_auxdata
+#define sqlite3_get_table              sqlite3_api->get_table
+#ifndef SQLITE_OMIT_DEPRECATED
+#define sqlite3_global_recover         sqlite3_api->global_recover
+#endif
+#define sqlite3_interrupt              sqlite3_api->interruptx
+#define sqlite3_last_insert_rowid      sqlite3_api->last_insert_rowid
+#define sqlite3_libversion             sqlite3_api->libversion
+#define sqlite3_libversion_number      sqlite3_api->libversion_number
+#define sqlite3_malloc                 sqlite3_api->malloc
+#define sqlite3_mprintf                sqlite3_api->mprintf
+#define sqlite3_open                   sqlite3_api->open
+#define sqlite3_open16                 sqlite3_api->open16
+#define sqlite3_prepare                sqlite3_api->prepare
+#define sqlite3_prepare16              sqlite3_api->prepare16
+#define sqlite3_prepare_v2             sqlite3_api->prepare_v2
+#define sqlite3_prepare16_v2           sqlite3_api->prepare16_v2
+#define sqlite3_profile                sqlite3_api->profile
+#define sqlite3_progress_handler       sqlite3_api->progress_handler
+#define sqlite3_realloc                sqlite3_api->realloc
+#define sqlite3_reset                  sqlite3_api->reset
+#define sqlite3_result_blob            sqlite3_api->result_blob
+#define sqlite3_result_double          sqlite3_api->result_double
+#define sqlite3_result_error           sqlite3_api->result_error
+#define sqlite3_result_error16         sqlite3_api->result_error16
+#define sqlite3_result_int             sqlite3_api->result_int
+#define sqlite3_result_int64           sqlite3_api->result_int64
+#define sqlite3_result_null            sqlite3_api->result_null
+#define sqlite3_result_text            sqlite3_api->result_text
+#define sqlite3_result_text16          sqlite3_api->result_text16
+#define sqlite3_result_text16be        sqlite3_api->result_text16be
+#define sqlite3_result_text16le        sqlite3_api->result_text16le
+#define sqlite3_result_value           sqlite3_api->result_value
+#define sqlite3_rollback_hook          sqlite3_api->rollback_hook
+#define sqlite3_set_authorizer         sqlite3_api->set_authorizer
+#define sqlite3_set_auxdata            sqlite3_api->set_auxdata
+#define sqlite3_snprintf               sqlite3_api->xsnprintf
+#define sqlite3_step                   sqlite3_api->step
+#define sqlite3_table_column_metadata  sqlite3_api->table_column_metadata
+#define sqlite3_thread_cleanup         sqlite3_api->thread_cleanup
+#define sqlite3_total_changes          sqlite3_api->total_changes
+#define sqlite3_trace                  sqlite3_api->trace
+#ifndef SQLITE_OMIT_DEPRECATED
+#define sqlite3_transfer_bindings      sqlite3_api->transfer_bindings
+#endif
+#define sqlite3_update_hook            sqlite3_api->update_hook
+#define sqlite3_user_data              sqlite3_api->user_data
+#define sqlite3_value_blob             sqlite3_api->value_blob
+#define sqlite3_value_bytes            sqlite3_api->value_bytes
+#define sqlite3_value_bytes16          sqlite3_api->value_bytes16
+#define sqlite3_value_double           sqlite3_api->value_double
+#define sqlite3_value_int              sqlite3_api->value_int
+#define sqlite3_value_int64            sqlite3_api->value_int64
+#define sqlite3_value_numeric_type     sqlite3_api->value_numeric_type
+#define sqlite3_value_text             sqlite3_api->value_text
+#define sqlite3_value_text16           sqlite3_api->value_text16
+#define sqlite3_value_text16be         sqlite3_api->value_text16be
+#define sqlite3_value_text16le         sqlite3_api->value_text16le
+#define sqlite3_value_type             sqlite3_api->value_type
+#define sqlite3_vmprintf               sqlite3_api->vmprintf
+#define sqlite3_vsnprintf              sqlite3_api->xvsnprintf
+#define sqlite3_overload_function      sqlite3_api->overload_function
+#define sqlite3_prepare_v2             sqlite3_api->prepare_v2
+#define sqlite3_prepare16_v2           sqlite3_api->prepare16_v2
+#define sqlite3_clear_bindings         sqlite3_api->clear_bindings
+#define sqlite3_bind_zeroblob          sqlite3_api->bind_zeroblob
+#define sqlite3_blob_bytes             sqlite3_api->blob_bytes
+#define sqlite3_blob_close             sqlite3_api->blob_close
+#define sqlite3_blob_open              sqlite3_api->blob_open
+#define sqlite3_blob_read              sqlite3_api->blob_read
+#define sqlite3_blob_write             sqlite3_api->blob_write
+#define sqlite3_create_collation_v2    sqlite3_api->create_collation_v2
+#define sqlite3_file_control           sqlite3_api->file_control
+#define sqlite3_memory_highwater       sqlite3_api->memory_highwater
+#define sqlite3_memory_used            sqlite3_api->memory_used
+#define sqlite3_mutex_alloc            sqlite3_api->mutex_alloc
+#define sqlite3_mutex_enter            sqlite3_api->mutex_enter
+#define sqlite3_mutex_free             sqlite3_api->mutex_free
+#define sqlite3_mutex_leave            sqlite3_api->mutex_leave
+#define sqlite3_mutex_try              sqlite3_api->mutex_try
+#define sqlite3_open_v2                sqlite3_api->open_v2
+#define sqlite3_release_memory         sqlite3_api->release_memory
+#define sqlite3_result_error_nomem     sqlite3_api->result_error_nomem
+#define sqlite3_result_error_toobig    sqlite3_api->result_error_toobig
+#define sqlite3_sleep                  sqlite3_api->sleep
+#define sqlite3_soft_heap_limit        sqlite3_api->soft_heap_limit
+#define sqlite3_vfs_find               sqlite3_api->vfs_find
+#define sqlite3_vfs_register           sqlite3_api->vfs_register
+#define sqlite3_vfs_unregister         sqlite3_api->vfs_unregister
+#define sqlite3_threadsafe             sqlite3_api->xthreadsafe
+#define sqlite3_result_zeroblob        sqlite3_api->result_zeroblob
+#define sqlite3_result_error_code      sqlite3_api->result_error_code
+#define sqlite3_test_control           sqlite3_api->test_control
+#define sqlite3_randomness             sqlite3_api->randomness
+#define sqlite3_context_db_handle      sqlite3_api->context_db_handle
+#define sqlite3_extended_result_codes  sqlite3_api->extended_result_codes
+#define sqlite3_limit                  sqlite3_api->limit
+#define sqlite3_next_stmt              sqlite3_api->next_stmt
+#define sqlite3_sql                    sqlite3_api->sql
+#define sqlite3_status                 sqlite3_api->status
+#define sqlite3_backup_finish          sqlite3_api->backup_finish
+#define sqlite3_backup_init            sqlite3_api->backup_init
+#define sqlite3_backup_pagecount       sqlite3_api->backup_pagecount
+#define sqlite3_backup_remaining       sqlite3_api->backup_remaining
+#define sqlite3_backup_step            sqlite3_api->backup_step
+#define sqlite3_compileoption_get      sqlite3_api->compileoption_get
+#define sqlite3_compileoption_used     sqlite3_api->compileoption_used
+#define sqlite3_create_function_v2     sqlite3_api->create_function_v2
+#define sqlite3_db_config              sqlite3_api->db_config
+#define sqlite3_db_mutex               sqlite3_api->db_mutex
+#define sqlite3_db_status              sqlite3_api->db_status
+#define sqlite3_extended_errcode       sqlite3_api->extended_errcode
+#define sqlite3_log                    sqlite3_api->log
+#define sqlite3_soft_heap_limit64      sqlite3_api->soft_heap_limit64
+#define sqlite3_sourceid               sqlite3_api->sourceid
+#define sqlite3_stmt_status            sqlite3_api->stmt_status
+#define sqlite3_strnicmp               sqlite3_api->strnicmp
+#define sqlite3_unlock_notify          sqlite3_api->unlock_notify
+#define sqlite3_wal_autocheckpoint     sqlite3_api->wal_autocheckpoint
+#define sqlite3_wal_checkpoint         sqlite3_api->wal_checkpoint
+#define sqlite3_wal_hook               sqlite3_api->wal_hook
+#define sqlite3_blob_reopen            sqlite3_api->blob_reopen
+#define sqlite3_vtab_config            sqlite3_api->vtab_config
+#define sqlite3_vtab_on_conflict       sqlite3_api->vtab_on_conflict
+/* Version 3.7.16 and later */
+#define sqlite3_close_v2               sqlite3_api->close_v2
+#define sqlite3_db_filename            sqlite3_api->db_filename
+#define sqlite3_db_readonly            sqlite3_api->db_readonly
+#define sqlite3_db_release_memory      sqlite3_api->db_release_memory
+#define sqlite3_errstr                 sqlite3_api->errstr
+#define sqlite3_stmt_busy              sqlite3_api->stmt_busy
+#define sqlite3_stmt_readonly          sqlite3_api->stmt_readonly
+#define sqlite3_stricmp                sqlite3_api->stricmp
+#define sqlite3_uri_boolean            sqlite3_api->uri_boolean
+#define sqlite3_uri_int64              sqlite3_api->uri_int64
+#define sqlite3_uri_parameter          sqlite3_api->uri_parameter
+#define sqlite3_uri_vsnprintf          sqlite3_api->xvsnprintf
+#define sqlite3_wal_checkpoint_v2      sqlite3_api->wal_checkpoint_v2
+/* Version 3.8.7 and later */
+#define sqlite3_auto_extension         sqlite3_api->auto_extension
+#define sqlite3_bind_blob64            sqlite3_api->bind_blob64
+#define sqlite3_bind_text64            sqlite3_api->bind_text64
+#define sqlite3_cancel_auto_extension  sqlite3_api->cancel_auto_extension
+#define sqlite3_load_extension         sqlite3_api->load_extension
+#define sqlite3_malloc64               sqlite3_api->malloc64
+#define sqlite3_msize                  sqlite3_api->msize
+#define sqlite3_realloc64              sqlite3_api->realloc64
+#define sqlite3_reset_auto_extension   sqlite3_api->reset_auto_extension
+#define sqlite3_result_blob64          sqlite3_api->result_blob64
+#define sqlite3_result_text64          sqlite3_api->result_text64
+#define sqlite3_strglob                sqlite3_api->strglob
+/* Version 3.8.11 and later */
+#define sqlite3_value_dup              sqlite3_api->value_dup
+#define sqlite3_value_free             sqlite3_api->value_free
+#define sqlite3_result_zeroblob64      sqlite3_api->result_zeroblob64
+#define sqlite3_bind_zeroblob64        sqlite3_api->bind_zeroblob64
+/* Version 3.9.0 and later */
+#define sqlite3_value_subtype          sqlite3_api->value_subtype
+#define sqlite3_result_subtype         sqlite3_api->result_subtype
+/* Version 3.10.0 and later */
+#define sqlite3_status64               sqlite3_api->status64
+#define sqlite3_strlike                sqlite3_api->strlike
+#define sqlite3_db_cacheflush          sqlite3_api->db_cacheflush
+/* Version 3.12.0 and later */
+#define sqlite3_system_errno           sqlite3_api->system_errno
+/* Version 3.14.0 and later */
+#define sqlite3_trace_v2               sqlite3_api->trace_v2
+#define sqlite3_expanded_sql           sqlite3_api->expanded_sql
+/* Version 3.18.0 and later */
+#define sqlite3_set_last_insert_rowid  sqlite3_api->set_last_insert_rowid
+/* Version 3.20.0 and later */
+#define sqlite3_prepare_v3             sqlite3_api->prepare_v3
+#define sqlite3_prepare16_v3           sqlite3_api->prepare16_v3
+#define sqlite3_bind_pointer           sqlite3_api->bind_pointer
+#define sqlite3_result_pointer         sqlite3_api->result_pointer
+#define sqlite3_value_pointer          sqlite3_api->value_pointer
+/* Version 3.22.0 and later */
+#define sqlite3_vtab_nochange          sqlite3_api->vtab_nochange
+#define sqlite3_value_nochange         sqlite3_api->value_nochange
+#define sqlite3_vtab_collation         sqlite3_api->vtab_collation
+/* Version 3.24.0 and later */
+#define sqlite3_keyword_count          sqlite3_api->keyword_count
+#define sqlite3_keyword_name           sqlite3_api->keyword_name
+#define sqlite3_keyword_check          sqlite3_api->keyword_check
+#define sqlite3_str_new                sqlite3_api->str_new
+#define sqlite3_str_finish             sqlite3_api->str_finish
+#define sqlite3_str_appendf            sqlite3_api->str_appendf
+#define sqlite3_str_vappendf           sqlite3_api->str_vappendf
+#define sqlite3_str_append             sqlite3_api->str_append
+#define sqlite3_str_appendall          sqlite3_api->str_appendall
+#define sqlite3_str_appendchar         sqlite3_api->str_appendchar
+#define sqlite3_str_reset              sqlite3_api->str_reset
+#define sqlite3_str_errcode            sqlite3_api->str_errcode
+#define sqlite3_str_length             sqlite3_api->str_length
+#define sqlite3_str_value              sqlite3_api->str_value
+/* Version 3.25.0 and later */
+#define sqlite3_create_window_function sqlite3_api->create_window_function
+/* Version 3.26.0 and later */
+#define sqlite3_normalized_sql         sqlite3_api->normalized_sql
+/* Version 3.28.0 and later */
+#define sqlite3_stmt_isexplain         sqlite3_api->stmt_isexplain
+#define sqlite3_value_frombind         sqlite3_api->value_frombind
+/* Version 3.30.0 and later */
+#define sqlite3_drop_modules           sqlite3_api->drop_modules
+/* Version 3.31.0 and later */
+#define sqlite3_hard_heap_limit64      sqlite3_api->hard_heap_limit64
+#define sqlite3_uri_key                sqlite3_api->uri_key
+#define sqlite3_filename_database      sqlite3_api->filename_database
+#define sqlite3_filename_journal       sqlite3_api->filename_journal
+#define sqlite3_filename_wal           sqlite3_api->filename_wal
+/* Version 3.32.0 and later */
+#define sqlite3_create_filename        sqlite3_api->create_filename
+#define sqlite3_free_filename          sqlite3_api->free_filename
+#define sqlite3_database_file_object   sqlite3_api->database_file_object
+/* Version 3.34.0 and later */
+#define sqlite3_txn_state              sqlite3_api->txn_state
+/* Version 3.36.1 and later */
+#define sqlite3_changes64              sqlite3_api->changes64
+#define sqlite3_total_changes64        sqlite3_api->total_changes64
+/* Version 3.37.0 and later */
+#define sqlite3_autovacuum_pages       sqlite3_api->autovacuum_pages
+/* Version 3.38.0 and later */
+#define sqlite3_error_offset           sqlite3_api->error_offset
+#define sqlite3_vtab_rhs_value         sqlite3_api->vtab_rhs_value
+#define sqlite3_vtab_distinct          sqlite3_api->vtab_distinct
+#define sqlite3_vtab_in                sqlite3_api->vtab_in
+#define sqlite3_vtab_in_first          sqlite3_api->vtab_in_first
+#define sqlite3_vtab_in_next           sqlite3_api->vtab_in_next
+/* Version 3.39.0 and later */
+#ifndef SQLITE_OMIT_DESERIALIZE
+#define sqlite3_deserialize            sqlite3_api->deserialize
+#define sqlite3_serialize              sqlite3_api->serialize
+#endif
+#define sqlite3_db_name                sqlite3_api->db_name
+#endif /* !defined(SQLITE_CORE) && !defined(SQLITE_OMIT_LOAD_EXTENSION) */
+
+#if !defined(SQLITE_CORE) && !defined(SQLITE_OMIT_LOAD_EXTENSION)
+  /* This case when the file really is being compiled as a loadable 
+  ** extension */
+# define SQLITE_EXTENSION_INIT1     const sqlite3_api_routines *sqlite3_api=0;
+# define SQLITE_EXTENSION_INIT2(v)  sqlite3_api=v;
+# define SQLITE_EXTENSION_INIT3     \
+    extern const sqlite3_api_routines *sqlite3_api;
+#else
+  /* This case when the file is being statically linked into the 
+  ** application */
+# define SQLITE_EXTENSION_INIT1     /*no-op*/
+# define SQLITE_EXTENSION_INIT2(v)  (void)v; /* unused parameter */
+# define SQLITE_EXTENSION_INIT3     /*no-op*/
+#endif
+
+#endif /* SQLITE3EXT_H */
+#else // USE_LIBSQLITE3
+ // If users really want to link against the system sqlite3 we
+// need to make this file a noop.
+ #endif

vendor/github.com/mattn/go-sqlite3/static_mock.go

@@ -0,0 +1,37 @@
+// Copyright (C) 2019 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build !cgo
+
+package sqlite3
+
+import (
+	"database/sql"
+	"database/sql/driver"
+	"errors"
+)
+
+var errorMsg = errors.New("Binary was compiled with 'CGO_ENABLED=0', go-sqlite3 requires cgo to work. This is a stub")
+
+func init() {
+	sql.Register("sqlite3", &SQLiteDriver{})
+}
+
+type (
+	SQLiteDriver struct {
+		Extensions  []string
+		ConnectHook func(*SQLiteConn) error
+	}
+	SQLiteConn struct{}
+)
+
+func (SQLiteDriver) Open(s string) (driver.Conn, error)                        { return nil, errorMsg }
+func (c *SQLiteConn) RegisterAggregator(string, interface{}, bool) error       { return errorMsg }
+func (c *SQLiteConn) RegisterAuthorizer(func(int, string, string, string) int) {}
+func (c *SQLiteConn) RegisterCollation(string, func(string, string) int) error { return errorMsg }
+func (c *SQLiteConn) RegisterCommitHook(func() int)                            {}
+func (c *SQLiteConn) RegisterFunc(string, interface{}, bool) error             { return errorMsg }
+func (c *SQLiteConn) RegisterRollbackHook(func())                              {}
+func (c *SQLiteConn) RegisterUpdateHook(func(int, string, string, int64))      {}

vendor/github.com/sirupsen/logrus/.gitignore

@@ -0,0 +1,4 @@
+logrus
+vendor
+
+.idea/

vendor/github.com/sirupsen/logrus/.golangci.yml

@@ -0,0 +1,40 @@
+run:
+  # do not run on test files yet
+  tests: false
+
+# all available settings of specific linters
+linters-settings:
+  errcheck:
+    # report about not checking of errors in type assetions: `a := b.(MyStruct)`;
+    # default is false: such cases aren't reported by default.
+    check-type-assertions: false
+
+    # report about assignment of errors to blank identifier: `num, _ := strconv.Atoi(numStr)`;
+    # default is false: such cases aren't reported by default.
+    check-blank: false
+
+  lll:
+    line-length: 100
+    tab-width: 4
+
+  prealloc:
+    simple: false
+    range-loops: false
+    for-loops: false
+
+  whitespace:
+    multi-if: false   # Enforces newlines (or comments) after every multi-line if statement
+    multi-func: false # Enforces newlines (or comments) after every multi-line function signature
+
+linters:
+  enable:
+    - megacheck
+    - govet
+  disable:
+    - maligned
+    - prealloc
+  disable-all: false
+  presets:
+    - bugs
+    - unused
+  fast: false

vendor/github.com/sirupsen/logrus/.travis.yml

@@ -0,0 +1,15 @@
+language: go
+go_import_path: github.com/sirupsen/logrus
+git:
+  depth: 1
+env:
+  - GO111MODULE=on
+go: 1.15.x
+os: linux
+install:
+  - ./travis/install.sh
+script:
+  - cd ci
+  - go run mage.go -v -w ../ crossBuild
+  - go run mage.go -v -w ../ lint
+  - go run mage.go -v -w ../ test

vendor/github.com/sirupsen/logrus/CHANGELOG.md

@@ -0,0 +1,259 @@
+# 1.8.1
+Code quality:
+  * move magefile in its own subdir/submodule to remove magefile dependency on logrus consumer
+  * improve timestamp format documentation
+
+Fixes:
+  * fix race condition on logger hooks
+
+
+# 1.8.0
+
+Correct versioning number replacing v1.7.1.
+
+# 1.7.1
+
+Beware this release has introduced a new public API and its semver is therefore incorrect.
+
+Code quality:
+  * use go 1.15 in travis
+  * use magefile as task runner
+
+Fixes:
+  * small fixes about new go 1.13 error formatting system
+  * Fix for long time race condiction with mutating data hooks
+
+Features:
+  * build support for zos
+
+# 1.7.0
+Fixes:
+  * the dependency toward a windows terminal library has been removed
+
+Features:
+  * a new buffer pool management API has been added
+  * a set of `<LogLevel>Fn()` functions have been added
+
+# 1.6.0
+Fixes:
+  * end of line cleanup
+  * revert the entry concurrency bug fix whic leads to deadlock under some circumstances
+  * update dependency on go-windows-terminal-sequences to fix a crash with go 1.14
+
+Features:
+  * add an option to the `TextFormatter` to completely disable fields quoting
+
+# 1.5.0
+Code quality:
+  * add golangci linter run on travis
+
+Fixes:
+  * add mutex for hooks concurrent access on `Entry` data
+  * caller function field for go1.14
+  * fix build issue for gopherjs target
+
+Feature:
+  * add an hooks/writer sub-package whose goal is to split output on different stream depending on the trace level
+  * add a `DisableHTMLEscape` option in the `JSONFormatter`
+  * add `ForceQuote` and `PadLevelText` options in the `TextFormatter`
+
+# 1.4.2
+  * Fixes build break for plan9, nacl, solaris
+# 1.4.1
+This new release introduces:
+  * Enhance TextFormatter to not print caller information when they are empty (#944)
+  * Remove dependency on golang.org/x/crypto (#932, #943)
+
+Fixes:
+  * Fix Entry.WithContext method to return a copy of the initial entry (#941)
+
+# 1.4.0
+This new release introduces:
+  * Add `DeferExitHandler`, similar to `RegisterExitHandler` but prepending the handler to the list of handlers (semantically like `defer`) (#848).
+  * Add `CallerPrettyfier` to `JSONFormatter` and `TextFormatter` (#909, #911)
+  * Add `Entry.WithContext()` and `Entry.Context`, to set a context on entries to be used e.g. in hooks (#919).
+
+Fixes:
+  * Fix wrong method calls `Logger.Print` and `Logger.Warningln` (#893).
+  * Update `Entry.Logf` to not do string formatting unless the log level is enabled (#903)
+  * Fix infinite recursion on unknown `Level.String()` (#907)
+  * Fix race condition in `getCaller` (#916).
+
+
+# 1.3.0
+This new release introduces:
+  * Log, Logf, Logln functions for Logger and Entry that take a Level
+
+Fixes:
+  * Building prometheus node_exporter on AIX (#840)
+  * Race condition in TextFormatter (#468)
+  * Travis CI import path (#868)
+  * Remove coloured output on Windows (#862)
+  * Pointer to func as field in JSONFormatter (#870)
+  * Properly marshal Levels (#873)
+
+# 1.2.0
+This new release introduces:
+  * A new method `SetReportCaller` in the `Logger` to enable the file, line and calling function from which the trace has been issued
+  * A new trace level named `Trace` whose level is below `Debug`
+  * A configurable exit function to be called upon a Fatal trace
+  * The `Level` object now implements `encoding.TextUnmarshaler` interface
+
+# 1.1.1
+This is a bug fix release.
+  * fix the build break on Solaris
+  * don't drop a whole trace in JSONFormatter when a field param is a function pointer which can not be serialized
+
+# 1.1.0
+This new release introduces:
+  * several fixes:
+    * a fix for a race condition on entry formatting
+    * proper cleanup of previously used entries before putting them back in the pool
+    * the extra new line at the end of message in text formatter has been removed
+  * a new global public API to check if a level is activated: IsLevelEnabled
+  * the following methods have been added to the Logger object
+    * IsLevelEnabled
+    * SetFormatter
+    * SetOutput
+    * ReplaceHooks
+  * introduction of go module
+  * an indent configuration for the json formatter
+  * output colour support for windows
+  * the field sort function is now configurable for text formatter
+  * the CLICOLOR and CLICOLOR\_FORCE environment variable support in text formater
+
+# 1.0.6
+
+This new release introduces:
+  * a new api WithTime which allows to easily force the time of the log entry
+    which is mostly useful for logger wrapper
+  * a fix reverting the immutability of the entry given as parameter to the hooks
+    a new configuration field of the json formatter in order to put all the fields
+    in a nested dictionnary
+  * a new SetOutput method in the Logger
+  * a new configuration of the textformatter to configure the name of the default keys
+  * a new configuration of the text formatter to disable the level truncation
+
+# 1.0.5
+
+* Fix hooks race (#707)
+* Fix panic deadlock (#695)
+
+# 1.0.4
+
+* Fix race when adding hooks (#612)
+* Fix terminal check in AppEngine (#635)
+
+# 1.0.3
+
+* Replace example files with testable examples
+
+# 1.0.2
+
+* bug: quote non-string values in text formatter (#583)
+* Make (*Logger) SetLevel a public method
+
+# 1.0.1
+
+* bug: fix escaping in text formatter (#575)
+
+# 1.0.0
+
+* Officially changed name to lower-case
+* bug: colors on Windows 10 (#541)
+* bug: fix race in accessing level (#512)
+
+# 0.11.5
+
+* feature: add writer and writerlevel to entry (#372)
+
+# 0.11.4
+
+* bug: fix undefined variable on solaris (#493)
+
+# 0.11.3
+
+* formatter: configure quoting of empty values (#484)
+* formatter: configure quoting character (default is `"`) (#484)
+* bug: fix not importing io correctly in non-linux environments (#481)
+
+# 0.11.2
+
+* bug: fix windows terminal detection (#476)
+
+# 0.11.1
+
+* bug: fix tty detection with custom out (#471)
+
+# 0.11.0
+
+* performance: Use bufferpool to allocate (#370)
+* terminal: terminal detection for app-engine (#343)
+* feature: exit handler (#375)
+
+# 0.10.0
+
+* feature: Add a test hook (#180)
+* feature: `ParseLevel` is now case-insensitive (#326)
+* feature: `FieldLogger` interface that generalizes `Logger` and `Entry` (#308)
+* performance: avoid re-allocations on `WithFields` (#335)
+
+# 0.9.0
+
+* logrus/text_formatter: don't emit empty msg
+* logrus/hooks/airbrake: move out of main repository
+* logrus/hooks/sentry: move out of main repository
+* logrus/hooks/papertrail: move out of main repository
+* logrus/hooks/bugsnag: move out of main repository
+* logrus/core: run tests with `-race`
+* logrus/core: detect TTY based on `stderr`
+* logrus/core: support `WithError` on logger
+* logrus/core: Solaris support
+
+# 0.8.7
+
+* logrus/core: fix possible race (#216)
+* logrus/doc: small typo fixes and doc improvements
+
+
+# 0.8.6
+
+* hooks/raven: allow passing an initialized client
+
+# 0.8.5
+
+* logrus/core: revert #208
+
+# 0.8.4
+
+* formatter/text: fix data race (#218)
+
+# 0.8.3
+
+* logrus/core: fix entry log level (#208)
+* logrus/core: improve performance of text formatter by 40%
+* logrus/core: expose `LevelHooks` type
+* logrus/core: add support for DragonflyBSD and NetBSD
+* formatter/text: print structs more verbosely
+
+# 0.8.2
+
+* logrus: fix more Fatal family functions
+
+# 0.8.1
+
+* logrus: fix not exiting on `Fatalf` and `Fatalln`
+
+# 0.8.0
+
+* logrus: defaults to stderr instead of stdout
+* hooks/sentry: add special field for `*http.Request`
+* formatter/text: ignore Windows for colors
+
+# 0.7.3
+
+* formatter/\*: allow configuration of timestamp layout
+
+# 0.7.2
+
+* formatter/text: Add configuration option for time format (#158)

vendor/github.com/sirupsen/logrus/LICENSE

@@ -0,0 +1,21 @@
+The MIT License (MIT)
+
+Copyright (c) 2014 Simon Eskildsen
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.

vendor/github.com/sirupsen/logrus/README.md

@@ -0,0 +1,513 @@
+# Logrus <img src="http://i.imgur.com/hTeVwmJ.png" width="40" height="40" alt=":walrus:" class="emoji" title=":walrus:"/> [![Build Status](https://github.com/sirupsen/logrus/workflows/CI/badge.svg)](https://github.com/sirupsen/logrus/actions?query=workflow%3ACI) [![Build Status](https://travis-ci.org/sirupsen/logrus.svg?branch=master)](https://travis-ci.org/sirupsen/logrus) [![Go Reference](https://pkg.go.dev/badge/github.com/sirupsen/logrus.svg)](https://pkg.go.dev/github.com/sirupsen/logrus)
+
+Logrus is a structured logger for Go (golang), completely API compatible with
+the standard library logger.
+
+**Logrus is in maintenance-mode.** We will not be introducing new features. It's
+simply too hard to do in a way that won't break many people's projects, which is
+the last thing you want from your Logging library (again...).
+
+This does not mean Logrus is dead. Logrus will continue to be maintained for
+security, (backwards compatible) bug fixes, and performance (where we are
+limited by the interface). 
+
+I believe Logrus' biggest contribution is to have played a part in today's
+widespread use of structured logging in Golang. There doesn't seem to be a
+reason to do a major, breaking iteration into Logrus V2, since the fantastic Go
+community has built those independently. Many fantastic alternatives have sprung
+up. Logrus would look like those, had it been re-designed with what we know
+about structured logging in Go today. Check out, for example,
+[Zerolog][zerolog], [Zap][zap], and [Apex][apex].
+
+[zerolog]: https://github.com/rs/zerolog
+[zap]: https://github.com/uber-go/zap
+[apex]: https://github.com/apex/log
+
+**Seeing weird case-sensitive problems?** It's in the past been possible to
+import Logrus as both upper- and lower-case. Due to the Go package environment,
+this caused issues in the community and we needed a standard. Some environments
+experienced problems with the upper-case variant, so the lower-case was decided.
+Everything using `logrus` will need to use the lower-case:
+`github.com/sirupsen/logrus`. Any package that isn't, should be changed.
+
+To fix Glide, see [these
+comments](https://github.com/sirupsen/logrus/issues/553#issuecomment-306591437).
+For an in-depth explanation of the casing issue, see [this
+comment](https://github.com/sirupsen/logrus/issues/570#issuecomment-313933276).
+
+Nicely color-coded in development (when a TTY is attached, otherwise just
+plain text):
+
+![Colored](http://i.imgur.com/PY7qMwd.png)
+
+With `log.SetFormatter(&log.JSONFormatter{})`, for easy parsing by logstash
+or Splunk:
+
+```json
+{"animal":"walrus","level":"info","msg":"A group of walrus emerges from the
+ocean","size":10,"time":"2014-03-10 19:57:38.562264131 -0400 EDT"}
+
+{"level":"warning","msg":"The group's number increased tremendously!",
+"number":122,"omg":true,"time":"2014-03-10 19:57:38.562471297 -0400 EDT"}
+
+{"animal":"walrus","level":"info","msg":"A giant walrus appears!",
+"size":10,"time":"2014-03-10 19:57:38.562500591 -0400 EDT"}
+
+{"animal":"walrus","level":"info","msg":"Tremendously sized cow enters the ocean.",
+"size":9,"time":"2014-03-10 19:57:38.562527896 -0400 EDT"}
+
+{"level":"fatal","msg":"The ice breaks!","number":100,"omg":true,
+"time":"2014-03-10 19:57:38.562543128 -0400 EDT"}
+```
+
+With the default `log.SetFormatter(&log.TextFormatter{})` when a TTY is not
+attached, the output is compatible with the
+[logfmt](http://godoc.org/github.com/kr/logfmt) format:
+
+```text
+time="2015-03-26T01:27:38-04:00" level=debug msg="Started observing beach" animal=walrus number=8
+time="2015-03-26T01:27:38-04:00" level=info msg="A group of walrus emerges from the ocean" animal=walrus size=10
+time="2015-03-26T01:27:38-04:00" level=warning msg="The group's number increased tremendously!" number=122 omg=true
+time="2015-03-26T01:27:38-04:00" level=debug msg="Temperature changes" temperature=-4
+time="2015-03-26T01:27:38-04:00" level=panic msg="It's over 9000!" animal=orca size=9009
+time="2015-03-26T01:27:38-04:00" level=fatal msg="The ice breaks!" err=&{0x2082280c0 map[animal:orca size:9009] 2015-03-26 01:27:38.441574009 -0400 EDT panic It's over 9000!} number=100 omg=true
+```
+To ensure this behaviour even if a TTY is attached, set your formatter as follows:
+
+```go
+	log.SetFormatter(&log.TextFormatter{
+		DisableColors: true,
+		FullTimestamp: true,
+	})
+```
+
+#### Logging Method Name
+
+If you wish to add the calling method as a field, instruct the logger via:
+```go
+log.SetReportCaller(true)
+```
+This adds the caller as 'method' like so:
+
+```json
+{"animal":"penguin","level":"fatal","method":"github.com/sirupsen/arcticcreatures.migrate","msg":"a penguin swims by",
+"time":"2014-03-10 19:57:38.562543129 -0400 EDT"}
+```
+
+```text
+time="2015-03-26T01:27:38-04:00" level=fatal method=github.com/sirupsen/arcticcreatures.migrate msg="a penguin swims by" animal=penguin
+```
+Note that this does add measurable overhead - the cost will depend on the version of Go, but is
+between 20 and 40% in recent tests with 1.6 and 1.7.  You can validate this in your
+environment via benchmarks: 
+```
+go test -bench=.*CallerTracing
+```
+
+
+#### Case-sensitivity
+
+The organization's name was changed to lower-case--and this will not be changed
+back. If you are getting import conflicts due to case sensitivity, please use
+the lower-case import: `github.com/sirupsen/logrus`.
+
+#### Example
+
+The simplest way to use Logrus is simply the package-level exported logger:
+
+```go
+package main
+
+import (
+  log "github.com/sirupsen/logrus"
+)
+
+func main() {
+  log.WithFields(log.Fields{
+    "animal": "walrus",
+  }).Info("A walrus appears")
+}
+```
+
+Note that it's completely api-compatible with the stdlib logger, so you can
+replace your `log` imports everywhere with `log "github.com/sirupsen/logrus"`
+and you'll now have the flexibility of Logrus. You can customize it all you
+want:
+
+```go
+package main
+
+import (
+  "os"
+  log "github.com/sirupsen/logrus"
+)
+
+func init() {
+  // Log as JSON instead of the default ASCII formatter.
+  log.SetFormatter(&log.JSONFormatter{})
+
+  // Output to stdout instead of the default stderr
+  // Can be any io.Writer, see below for File example
+  log.SetOutput(os.Stdout)
+
+  // Only log the warning severity or above.
+  log.SetLevel(log.WarnLevel)
+}
+
+func main() {
+  log.WithFields(log.Fields{
+    "animal": "walrus",
+    "size":   10,
+  }).Info("A group of walrus emerges from the ocean")
+
+  log.WithFields(log.Fields{
+    "omg":    true,
+    "number": 122,
+  }).Warn("The group's number increased tremendously!")
+
+  log.WithFields(log.Fields{
+    "omg":    true,
+    "number": 100,
+  }).Fatal("The ice breaks!")
+
+  // A common pattern is to re-use fields between logging statements by re-using
+  // the logrus.Entry returned from WithFields()
+  contextLogger := log.WithFields(log.Fields{
+    "common": "this is a common field",
+    "other": "I also should be logged always",
+  })
+
+  contextLogger.Info("I'll be logged with common and other field")
+  contextLogger.Info("Me too")
+}
+```
+
+For more advanced usage such as logging to multiple locations from the same
+application, you can also create an instance of the `logrus` Logger:
+
+```go
+package main
+
+import (
+  "os"
+  "github.com/sirupsen/logrus"
+)
+
+// Create a new instance of the logger. You can have any number of instances.
+var log = logrus.New()
+
+func main() {
+  // The API for setting attributes is a little different than the package level
+  // exported logger. See Godoc.
+  log.Out = os.Stdout
+
+  // You could set this to any `io.Writer` such as a file
+  // file, err := os.OpenFile("logrus.log", os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0666)
+  // if err == nil {
+  //  log.Out = file
+  // } else {
+  //  log.Info("Failed to log to file, using default stderr")
+  // }
+
+  log.WithFields(logrus.Fields{
+    "animal": "walrus",
+    "size":   10,
+  }).Info("A group of walrus emerges from the ocean")
+}
+```
+
+#### Fields
+
+Logrus encourages careful, structured logging through logging fields instead of
+long, unparseable error messages. For example, instead of: `log.Fatalf("Failed
+to send event %s to topic %s with key %d")`, you should log the much more
+discoverable:
+
+```go
+log.WithFields(log.Fields{
+  "event": event,
+  "topic": topic,
+  "key": key,
+}).Fatal("Failed to send event")
+```
+
+We've found this API forces you to think about logging in a way that produces
+much more useful logging messages. We've been in countless situations where just
+a single added field to a log statement that was already there would've saved us
+hours. The `WithFields` call is optional.
+
+In general, with Logrus using any of the `printf`-family functions should be
+seen as a hint you should add a field, however, you can still use the
+`printf`-family functions with Logrus.
+
+#### Default Fields
+
+Often it's helpful to have fields _always_ attached to log statements in an
+application or parts of one. For example, you may want to always log the
+`request_id` and `user_ip` in the context of a request. Instead of writing
+`log.WithFields(log.Fields{"request_id": request_id, "user_ip": user_ip})` on
+every line, you can create a `logrus.Entry` to pass around instead:
+
+```go
+requestLogger := log.WithFields(log.Fields{"request_id": request_id, "user_ip": user_ip})
+requestLogger.Info("something happened on that request") # will log request_id and user_ip
+requestLogger.Warn("something not great happened")
+```
+
+#### Hooks
+
+You can add hooks for logging levels. For example to send errors to an exception
+tracking service on `Error`, `Fatal` and `Panic`, info to StatsD or log to
+multiple places simultaneously, e.g. syslog.
+
+Logrus comes with [built-in hooks](hooks/). Add those, or your custom hook, in
+`init`:
+
+```go
+import (
+  log "github.com/sirupsen/logrus"
+  "gopkg.in/gemnasium/logrus-airbrake-hook.v2" // the package is named "airbrake"
+  logrus_syslog "github.com/sirupsen/logrus/hooks/syslog"
+  "log/syslog"
+)
+
+func init() {
+
+  // Use the Airbrake hook to report errors that have Error severity or above to
+  // an exception tracker. You can create custom hooks, see the Hooks section.
+  log.AddHook(airbrake.NewHook(123, "xyz", "production"))
+
+  hook, err := logrus_syslog.NewSyslogHook("udp", "localhost:514", syslog.LOG_INFO, "")
+  if err != nil {
+    log.Error("Unable to connect to local syslog daemon")
+  } else {
+    log.AddHook(hook)
+  }
+}
+```
+Note: Syslog hook also support connecting to local syslog (Ex. "/dev/log" or "/var/run/syslog" or "/var/run/log"). For the detail, please check the [syslog hook README](hooks/syslog/README.md).
+
+A list of currently known service hooks can be found in this wiki [page](https://github.com/sirupsen/logrus/wiki/Hooks)
+
+
+#### Level logging
+
+Logrus has seven logging levels: Trace, Debug, Info, Warning, Error, Fatal and Panic.
+
+```go
+log.Trace("Something very low level.")
+log.Debug("Useful debugging information.")
+log.Info("Something noteworthy happened!")
+log.Warn("You should probably take a look at this.")
+log.Error("Something failed but I'm not quitting.")
+// Calls os.Exit(1) after logging
+log.Fatal("Bye.")
+// Calls panic() after logging
+log.Panic("I'm bailing.")
+```
+
+You can set the logging level on a `Logger`, then it will only log entries with
+that severity or anything above it:
+
+```go
+// Will log anything that is info or above (warn, error, fatal, panic). Default.
+log.SetLevel(log.InfoLevel)
+```
+
+It may be useful to set `log.Level = logrus.DebugLevel` in a debug or verbose
+environment if your application has that.
+
+#### Entries
+
+Besides the fields added with `WithField` or `WithFields` some fields are
+automatically added to all logging events:
+
+1. `time`. The timestamp when the entry was created.
+2. `msg`. The logging message passed to `{Info,Warn,Error,Fatal,Panic}` after
+   the `AddFields` call. E.g. `Failed to send event.`
+3. `level`. The logging level. E.g. `info`.
+
+#### Environments
+
+Logrus has no notion of environment.
+
+If you wish for hooks and formatters to only be used in specific environments,
+you should handle that yourself. For example, if your application has a global
+variable `Environment`, which is a string representation of the environment you
+could do:
+
+```go
+import (
+  log "github.com/sirupsen/logrus"
+)
+
+func init() {
+  // do something here to set environment depending on an environment variable
+  // or command-line flag
+  if Environment == "production" {
+    log.SetFormatter(&log.JSONFormatter{})
+  } else {
+    // The TextFormatter is default, you don't actually have to do this.
+    log.SetFormatter(&log.TextFormatter{})
+  }
+}
+```
+
+This configuration is how `logrus` was intended to be used, but JSON in
+production is mostly only useful if you do log aggregation with tools like
+Splunk or Logstash.
+
+#### Formatters
+
+The built-in logging formatters are:
+
+* `logrus.TextFormatter`. Logs the event in colors if stdout is a tty, otherwise
+  without colors.
+  * *Note:* to force colored output when there is no TTY, set the `ForceColors`
+    field to `true`.  To force no colored output even if there is a TTY  set the
+    `DisableColors` field to `true`. For Windows, see
+    [github.com/mattn/go-colorable](https://github.com/mattn/go-colorable).
+  * When colors are enabled, levels are truncated to 4 characters by default. To disable
+    truncation set the `DisableLevelTruncation` field to `true`.
+  * When outputting to a TTY, it's often helpful to visually scan down a column where all the levels are the same width. Setting the `PadLevelText` field to `true` enables this behavior, by adding padding to the level text.
+  * All options are listed in the [generated docs](https://godoc.org/github.com/sirupsen/logrus#TextFormatter).
+* `logrus.JSONFormatter`. Logs fields as JSON.
+  * All options are listed in the [generated docs](https://godoc.org/github.com/sirupsen/logrus#JSONFormatter).
+
+Third party logging formatters:
+
+* [`FluentdFormatter`](https://github.com/joonix/log). Formats entries that can be parsed by Kubernetes and Google Container Engine.
+* [`GELF`](https://github.com/fabienm/go-logrus-formatters). Formats entries so they comply to Graylog's [GELF 1.1 specification](http://docs.graylog.org/en/2.4/pages/gelf.html).
+* [`logstash`](https://github.com/bshuster-repo/logrus-logstash-hook). Logs fields as [Logstash](http://logstash.net) Events.
+* [`prefixed`](https://github.com/x-cray/logrus-prefixed-formatter). Displays log entry source along with alternative layout.
+* [`zalgo`](https://github.com/aybabtme/logzalgo). Invoking the Power of Zalgo.
+* [`nested-logrus-formatter`](https://github.com/antonfisher/nested-logrus-formatter). Converts logrus fields to a nested structure.
+* [`powerful-logrus-formatter`](https://github.com/zput/zxcTool). get fileName, log's line number and the latest function's name when print log; Sava log to files.
+* [`caption-json-formatter`](https://github.com/nolleh/caption_json_formatter). logrus's message json formatter with human-readable caption added.
+
+You can define your formatter by implementing the `Formatter` interface,
+requiring a `Format` method. `Format` takes an `*Entry`. `entry.Data` is a
+`Fields` type (`map[string]interface{}`) with all your fields as well as the
+default ones (see Entries section above):
+
+```go
+type MyJSONFormatter struct {
+}
+
+log.SetFormatter(new(MyJSONFormatter))
+
+func (f *MyJSONFormatter) Format(entry *Entry) ([]byte, error) {
+  // Note this doesn't include Time, Level and Message which are available on
+  // the Entry. Consult `godoc` on information about those fields or read the
+  // source of the official loggers.
+  serialized, err := json.Marshal(entry.Data)
+    if err != nil {
+      return nil, fmt.Errorf("Failed to marshal fields to JSON, %w", err)
+    }
+  return append(serialized, '\n'), nil
+}
+```
+
+#### Logger as an `io.Writer`
+
+Logrus can be transformed into an `io.Writer`. That writer is the end of an `io.Pipe` and it is your responsibility to close it.
+
+```go
+w := logger.Writer()
+defer w.Close()
+
+srv := http.Server{
+    // create a stdlib log.Logger that writes to
+    // logrus.Logger.
+    ErrorLog: log.New(w, "", 0),
+}
+```
+
+Each line written to that writer will be printed the usual way, using formatters
+and hooks. The level for those entries is `info`.
+
+This means that we can override the standard library logger easily:
+
+```go
+logger := logrus.New()
+logger.Formatter = &logrus.JSONFormatter{}
+
+// Use logrus for standard log output
+// Note that `log` here references stdlib's log
+// Not logrus imported under the name `log`.
+log.SetOutput(logger.Writer())
+```
+
+#### Rotation
+
+Log rotation is not provided with Logrus. Log rotation should be done by an
+external program (like `logrotate(8)`) that can compress and delete old log
+entries. It should not be a feature of the application-level logger.
+
+#### Tools
+
+| Tool | Description |
+| ---- | ----------- |
+|[Logrus Mate](https://github.com/gogap/logrus_mate)|Logrus mate is a tool for Logrus to manage loggers, you can initial logger's level, hook and formatter by config file, the logger will be generated with different configs in different environments.|
+|[Logrus Viper Helper](https://github.com/heirko/go-contrib/tree/master/logrusHelper)|An Helper around Logrus to wrap with spf13/Viper to load configuration with fangs! And to simplify Logrus configuration use some behavior of [Logrus Mate](https://github.com/gogap/logrus_mate). [sample](https://github.com/heirko/iris-contrib/blob/master/middleware/logrus-logger/example) |
+
+#### Testing
+
+Logrus has a built in facility for asserting the presence of log messages. This is implemented through the `test` hook and provides:
+
+* decorators for existing logger (`test.NewLocal` and `test.NewGlobal`) which basically just adds the `test` hook
+* a test logger (`test.NewNullLogger`) that just records log messages (and does not output any):
+
+```go
+import(
+  "github.com/sirupsen/logrus"
+  "github.com/sirupsen/logrus/hooks/test"
+  "github.com/stretchr/testify/assert"
+  "testing"
+)
+
+func TestSomething(t*testing.T){
+  logger, hook := test.NewNullLogger()
+  logger.Error("Helloerror")
+
+  assert.Equal(t, 1, len(hook.Entries))
+  assert.Equal(t, logrus.ErrorLevel, hook.LastEntry().Level)
+  assert.Equal(t, "Helloerror", hook.LastEntry().Message)
+
+  hook.Reset()
+  assert.Nil(t, hook.LastEntry())
+}
+```
+
+#### Fatal handlers
+
+Logrus can register one or more functions that will be called when any `fatal`
+level message is logged. The registered handlers will be executed before
+logrus performs an `os.Exit(1)`. This behavior may be helpful if callers need
+to gracefully shutdown. Unlike a `panic("Something went wrong...")` call which can be intercepted with a deferred `recover` a call to `os.Exit(1)` can not be intercepted.
+
+```
+...
+handler := func() {
+  // gracefully shutdown something...
+}
+logrus.RegisterExitHandler(handler)
+...
+```
+
+#### Thread safety
+
+By default, Logger is protected by a mutex for concurrent writes. The mutex is held when calling hooks and writing logs.
+If you are sure such locking is not needed, you can call logger.SetNoLock() to disable the locking.
+
+Situation when locking is not needed includes:
+
+* You have no hooks registered, or hooks calling is already thread-safe.
+
+* Writing to logger.Out is already thread-safe, for example:
+
+  1) logger.Out is protected by locks.
+
+  2) logger.Out is an os.File handler opened with `O_APPEND` flag, and every write is smaller than 4k. (This allows multi-thread/multi-process writing)
+
+     (Refer to http://www.notthewizard.com/2014/06/17/are-files-appends-really-atomic/)

vendor/github.com/sirupsen/logrus/alt_exit.go

@@ -0,0 +1,76 @@
+package logrus
+
+// The following code was sourced and modified from the
+// https://github.com/tebeka/atexit package governed by the following license:
+//
+// Copyright (c) 2012 Miki Tebeka <miki.tebeka@gmail.com>.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy of
+// this software and associated documentation files (the "Software"), to deal in
+// the Software without restriction, including without limitation the rights to
+// use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+// the Software, and to permit persons to whom the Software is furnished to do so,
+// subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+// FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+// COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+// IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+// CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+import (
+	"fmt"
+	"os"
+)
+
+var handlers = []func(){}
+
+func runHandler(handler func()) {
+	defer func() {
+		if err := recover(); err != nil {
+			fmt.Fprintln(os.Stderr, "Error: Logrus exit handler error:", err)
+		}
+	}()
+
+	handler()
+}
+
+func runHandlers() {
+	for _, handler := range handlers {
+		runHandler(handler)
+	}
+}
+
+// Exit runs all the Logrus atexit handlers and then terminates the program using os.Exit(code)
+func Exit(code int) {
+	runHandlers()
+	os.Exit(code)
+}
+
+// RegisterExitHandler appends a Logrus Exit handler to the list of handlers,
+// call logrus.Exit to invoke all handlers. The handlers will also be invoked when
+// any Fatal log entry is made.
+//
+// This method is useful when a caller wishes to use logrus to log a fatal
+// message but also needs to gracefully shutdown. An example usecase could be
+// closing database connections, or sending a alert that the application is
+// closing.
+func RegisterExitHandler(handler func()) {
+	handlers = append(handlers, handler)
+}
+
+// DeferExitHandler prepends a Logrus Exit handler to the list of handlers,
+// call logrus.Exit to invoke all handlers. The handlers will also be invoked when
+// any Fatal log entry is made.
+//
+// This method is useful when a caller wishes to use logrus to log a fatal
+// message but also needs to gracefully shutdown. An example usecase could be
+// closing database connections, or sending a alert that the application is
+// closing.
+func DeferExitHandler(handler func()) {
+	handlers = append([]func(){handler}, handlers...)
+}

vendor/github.com/sirupsen/logrus/appveyor.yml

@@ -0,0 +1,14 @@
+version: "{build}"
+platform: x64
+clone_folder: c:\gopath\src\github.com\sirupsen\logrus
+environment:
+  GOPATH: c:\gopath
+branches:
+  only:
+    - master
+install:
+  - set PATH=%GOPATH%\bin;c:\go\bin;%PATH%
+  - go version
+build_script:
+  - go get -t
+  - go test

vendor/github.com/sirupsen/logrus/buffer_pool.go

@@ -0,0 +1,43 @@
+package logrus
+
+import (
+	"bytes"
+	"sync"
+)
+
+var (
+	bufferPool BufferPool
+)
+
+type BufferPool interface {
+	Put(*bytes.Buffer)
+	Get() *bytes.Buffer
+}
+
+type defaultPool struct {
+	pool *sync.Pool
+}
+
+func (p *defaultPool) Put(buf *bytes.Buffer) {
+	p.pool.Put(buf)
+}
+
+func (p *defaultPool) Get() *bytes.Buffer {
+	return p.pool.Get().(*bytes.Buffer)
+}
+
+// SetBufferPool allows to replace the default logrus buffer pool
+// to better meets the specific needs of an application.
+func SetBufferPool(bp BufferPool) {
+	bufferPool = bp
+}
+
+func init() {
+	SetBufferPool(&defaultPool{
+		pool: &sync.Pool{
+			New: func() interface{} {
+				return new(bytes.Buffer)
+			},
+		},
+	})
+}

vendor/github.com/sirupsen/logrus/doc.go

@@ -0,0 +1,26 @@
+/*
+Package logrus is a structured logger for Go, completely API compatible with the standard library logger.
+
+
+The simplest way to use Logrus is simply the package-level exported logger:
+
+  package main
+
+  import (
+    log "github.com/sirupsen/logrus"
+  )
+
+  func main() {
+    log.WithFields(log.Fields{
+      "animal": "walrus",
+      "number": 1,
+      "size":   10,
+    }).Info("A walrus appears")
+  }
+
+Output:
+  time="2015-09-07T08:48:33Z" level=info msg="A walrus appears" animal=walrus number=1 size=10
+
+For a full guide visit https://github.com/sirupsen/logrus
+*/
+package logrus

vendor/github.com/sirupsen/logrus/entry.go

@@ -0,0 +1,442 @@
+package logrus
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"os"
+	"reflect"
+	"runtime"
+	"strings"
+	"sync"
+	"time"
+)
+
+var (
+
+	// qualified package name, cached at first use
+	logrusPackage string
+
+	// Positions in the call stack when tracing to report the calling method
+	minimumCallerDepth int
+
+	// Used for caller information initialisation
+	callerInitOnce sync.Once
+)
+
+const (
+	maximumCallerDepth int = 25
+	knownLogrusFrames  int = 4
+)
+
+func init() {
+	// start at the bottom of the stack before the package-name cache is primed
+	minimumCallerDepth = 1
+}
+
+// Defines the key when adding errors using WithError.
+var ErrorKey = "error"
+
+// An entry is the final or intermediate Logrus logging entry. It contains all
+// the fields passed with WithField{,s}. It's finally logged when Trace, Debug,
+// Info, Warn, Error, Fatal or Panic is called on it. These objects can be
+// reused and passed around as much as you wish to avoid field duplication.
+type Entry struct {
+	Logger *Logger
+
+	// Contains all the fields set by the user.
+	Data Fields
+
+	// Time at which the log entry was created
+	Time time.Time
+
+	// Level the log entry was logged at: Trace, Debug, Info, Warn, Error, Fatal or Panic
+	// This field will be set on entry firing and the value will be equal to the one in Logger struct field.
+	Level Level
+
+	// Calling method, with package name
+	Caller *runtime.Frame
+
+	// Message passed to Trace, Debug, Info, Warn, Error, Fatal or Panic
+	Message string
+
+	// When formatter is called in entry.log(), a Buffer may be set to entry
+	Buffer *bytes.Buffer
+
+	// Contains the context set by the user. Useful for hook processing etc.
+	Context context.Context
+
+	// err may contain a field formatting error
+	err string
+}
+
+func NewEntry(logger *Logger) *Entry {
+	return &Entry{
+		Logger: logger,
+		// Default is three fields, plus one optional.  Give a little extra room.
+		Data: make(Fields, 6),
+	}
+}
+
+func (entry *Entry) Dup() *Entry {
+	data := make(Fields, len(entry.Data))
+	for k, v := range entry.Data {
+		data[k] = v
+	}
+	return &Entry{Logger: entry.Logger, Data: data, Time: entry.Time, Context: entry.Context, err: entry.err}
+}
+
+// Returns the bytes representation of this entry from the formatter.
+func (entry *Entry) Bytes() ([]byte, error) {
+	return entry.Logger.Formatter.Format(entry)
+}
+
+// Returns the string representation from the reader and ultimately the
+// formatter.
+func (entry *Entry) String() (string, error) {
+	serialized, err := entry.Bytes()
+	if err != nil {
+		return "", err
+	}
+	str := string(serialized)
+	return str, nil
+}
+
+// Add an error as single field (using the key defined in ErrorKey) to the Entry.
+func (entry *Entry) WithError(err error) *Entry {
+	return entry.WithField(ErrorKey, err)
+}
+
+// Add a context to the Entry.
+func (entry *Entry) WithContext(ctx context.Context) *Entry {
+	dataCopy := make(Fields, len(entry.Data))
+	for k, v := range entry.Data {
+		dataCopy[k] = v
+	}
+	return &Entry{Logger: entry.Logger, Data: dataCopy, Time: entry.Time, err: entry.err, Context: ctx}
+}
+
+// Add a single field to the Entry.
+func (entry *Entry) WithField(key string, value interface{}) *Entry {
+	return entry.WithFields(Fields{key: value})
+}
+
+// Add a map of fields to the Entry.
+func (entry *Entry) WithFields(fields Fields) *Entry {
+	data := make(Fields, len(entry.Data)+len(fields))
+	for k, v := range entry.Data {
+		data[k] = v
+	}
+	fieldErr := entry.err
+	for k, v := range fields {
+		isErrField := false
+		if t := reflect.TypeOf(v); t != nil {
+			switch {
+			case t.Kind() == reflect.Func, t.Kind() == reflect.Ptr && t.Elem().Kind() == reflect.Func:
+				isErrField = true
+			}
+		}
+		if isErrField {
+			tmp := fmt.Sprintf("can not add field %q", k)
+			if fieldErr != "" {
+				fieldErr = entry.err + ", " + tmp
+			} else {
+				fieldErr = tmp
+			}
+		} else {
+			data[k] = v
+		}
+	}
+	return &Entry{Logger: entry.Logger, Data: data, Time: entry.Time, err: fieldErr, Context: entry.Context}
+}
+
+// Overrides the time of the Entry.
+func (entry *Entry) WithTime(t time.Time) *Entry {
+	dataCopy := make(Fields, len(entry.Data))
+	for k, v := range entry.Data {
+		dataCopy[k] = v
+	}
+	return &Entry{Logger: entry.Logger, Data: dataCopy, Time: t, err: entry.err, Context: entry.Context}
+}
+
+// getPackageName reduces a fully qualified function name to the package name
+// There really ought to be to be a better way...
+func getPackageName(f string) string {
+	for {
+		lastPeriod := strings.LastIndex(f, ".")
+		lastSlash := strings.LastIndex(f, "/")
+		if lastPeriod > lastSlash {
+			f = f[:lastPeriod]
+		} else {
+			break
+		}
+	}
+
+	return f
+}
+
+// getCaller retrieves the name of the first non-logrus calling function
+func getCaller() *runtime.Frame {
+	// cache this package's fully-qualified name
+	callerInitOnce.Do(func() {
+		pcs := make([]uintptr, maximumCallerDepth)
+		_ = runtime.Callers(0, pcs)
+
+		// dynamic get the package name and the minimum caller depth
+		for i := 0; i < maximumCallerDepth; i++ {
+			funcName := runtime.FuncForPC(pcs[i]).Name()
+			if strings.Contains(funcName, "getCaller") {
+				logrusPackage = getPackageName(funcName)
+				break
+			}
+		}
+
+		minimumCallerDepth = knownLogrusFrames
+	})
+
+	// Restrict the lookback frames to avoid runaway lookups
+	pcs := make([]uintptr, maximumCallerDepth)
+	depth := runtime.Callers(minimumCallerDepth, pcs)
+	frames := runtime.CallersFrames(pcs[:depth])
+
+	for f, again := frames.Next(); again; f, again = frames.Next() {
+		pkg := getPackageName(f.Function)
+
+		// If the caller isn't part of this package, we're done
+		if pkg != logrusPackage {
+			return &f //nolint:scopelint
+		}
+	}
+
+	// if we got here, we failed to find the caller's context
+	return nil
+}
+
+func (entry Entry) HasCaller() (has bool) {
+	return entry.Logger != nil &&
+		entry.Logger.ReportCaller &&
+		entry.Caller != nil
+}
+
+func (entry *Entry) log(level Level, msg string) {
+	var buffer *bytes.Buffer
+
+	newEntry := entry.Dup()
+
+	if newEntry.Time.IsZero() {
+		newEntry.Time = time.Now()
+	}
+
+	newEntry.Level = level
+	newEntry.Message = msg
+
+	newEntry.Logger.mu.Lock()
+	reportCaller := newEntry.Logger.ReportCaller
+	bufPool := newEntry.getBufferPool()
+	newEntry.Logger.mu.Unlock()
+
+	if reportCaller {
+		newEntry.Caller = getCaller()
+	}
+
+	newEntry.fireHooks()
+	buffer = bufPool.Get()
+	defer func() {
+		newEntry.Buffer = nil
+		buffer.Reset()
+		bufPool.Put(buffer)
+	}()
+	buffer.Reset()
+	newEntry.Buffer = buffer
+
+	newEntry.write()
+
+	newEntry.Buffer = nil
+
+	// To avoid Entry#log() returning a value that only would make sense for
+	// panic() to use in Entry#Panic(), we avoid the allocation by checking
+	// directly here.
+	if level <= PanicLevel {
+		panic(newEntry)
+	}
+}
+
+func (entry *Entry) getBufferPool() (pool BufferPool) {
+	if entry.Logger.BufferPool != nil {
+		return entry.Logger.BufferPool
+	}
+	return bufferPool
+}
+
+func (entry *Entry) fireHooks() {
+	var tmpHooks LevelHooks
+	entry.Logger.mu.Lock()
+	tmpHooks = make(LevelHooks, len(entry.Logger.Hooks))
+	for k, v := range entry.Logger.Hooks {
+		tmpHooks[k] = v
+	}
+	entry.Logger.mu.Unlock()
+
+	err := tmpHooks.Fire(entry.Level, entry)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "Failed to fire hook: %v\n", err)
+	}
+}
+
+func (entry *Entry) write() {
+	entry.Logger.mu.Lock()
+	defer entry.Logger.mu.Unlock()
+	serialized, err := entry.Logger.Formatter.Format(entry)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "Failed to obtain reader, %v\n", err)
+		return
+	}
+	if _, err := entry.Logger.Out.Write(serialized); err != nil {
+		fmt.Fprintf(os.Stderr, "Failed to write to log, %v\n", err)
+	}
+}
+
+// Log will log a message at the level given as parameter.
+// Warning: using Log at Panic or Fatal level will not respectively Panic nor Exit.
+// For this behaviour Entry.Panic or Entry.Fatal should be used instead.
+func (entry *Entry) Log(level Level, args ...interface{}) {
+	if entry.Logger.IsLevelEnabled(level) {
+		entry.log(level, fmt.Sprint(args...))
+	}
+}
+
+func (entry *Entry) Trace(args ...interface{}) {
+	entry.Log(TraceLevel, args...)
+}
+
+func (entry *Entry) Debug(args ...interface{}) {
+	entry.Log(DebugLevel, args...)
+}
+
+func (entry *Entry) Print(args ...interface{}) {
+	entry.Info(args...)
+}
+
+func (entry *Entry) Info(args ...interface{}) {
+	entry.Log(InfoLevel, args...)
+}
+
+func (entry *Entry) Warn(args ...interface{}) {
+	entry.Log(WarnLevel, args...)
+}
+
+func (entry *Entry) Warning(args ...interface{}) {
+	entry.Warn(args...)
+}
+
+func (entry *Entry) Error(args ...interface{}) {
+	entry.Log(ErrorLevel, args...)
+}
+
+func (entry *Entry) Fatal(args ...interface{}) {
+	entry.Log(FatalLevel, args...)
+	entry.Logger.Exit(1)
+}
+
+func (entry *Entry) Panic(args ...interface{}) {
+	entry.Log(PanicLevel, args...)
+}
+
+// Entry Printf family functions
+
+func (entry *Entry) Logf(level Level, format string, args ...interface{}) {
+	if entry.Logger.IsLevelEnabled(level) {
+		entry.Log(level, fmt.Sprintf(format, args...))
+	}
+}
+
+func (entry *Entry) Tracef(format string, args ...interface{}) {
+	entry.Logf(TraceLevel, format, args...)
+}
+
+func (entry *Entry) Debugf(format string, args ...interface{}) {
+	entry.Logf(DebugLevel, format, args...)
+}
+
+func (entry *Entry) Infof(format string, args ...interface{}) {
+	entry.Logf(InfoLevel, format, args...)
+}
+
+func (entry *Entry) Printf(format string, args ...interface{}) {
+	entry.Infof(format, args...)
+}
+
+func (entry *Entry) Warnf(format string, args ...interface{}) {
+	entry.Logf(WarnLevel, format, args...)
+}
+
+func (entry *Entry) Warningf(format string, args ...interface{}) {
+	entry.Warnf(format, args...)
+}
+
+func (entry *Entry) Errorf(format string, args ...interface{}) {
+	entry.Logf(ErrorLevel, format, args...)
+}
+
+func (entry *Entry) Fatalf(format string, args ...interface{}) {
+	entry.Logf(FatalLevel, format, args...)
+	entry.Logger.Exit(1)
+}
+
+func (entry *Entry) Panicf(format string, args ...interface{}) {
+	entry.Logf(PanicLevel, format, args...)
+}
+
+// Entry Println family functions
+
+func (entry *Entry) Logln(level Level, args ...interface{}) {
+	if entry.Logger.IsLevelEnabled(level) {
+		entry.Log(level, entry.sprintlnn(args...))
+	}
+}
+
+func (entry *Entry) Traceln(args ...interface{}) {
+	entry.Logln(TraceLevel, args...)
+}
+
+func (entry *Entry) Debugln(args ...interface{}) {
+	entry.Logln(DebugLevel, args...)
+}
+
+func (entry *Entry) Infoln(args ...interface{}) {
+	entry.Logln(InfoLevel, args...)
+}
+
+func (entry *Entry) Println(args ...interface{}) {
+	entry.Infoln(args...)
+}
+
+func (entry *Entry) Warnln(args ...interface{}) {
+	entry.Logln(WarnLevel, args...)
+}
+
+func (entry *Entry) Warningln(args ...interface{}) {
+	entry.Warnln(args...)
+}
+
+func (entry *Entry) Errorln(args ...interface{}) {
+	entry.Logln(ErrorLevel, args...)
+}
+
+func (entry *Entry) Fatalln(args ...interface{}) {
+	entry.Logln(FatalLevel, args...)
+	entry.Logger.Exit(1)
+}
+
+func (entry *Entry) Panicln(args ...interface{}) {
+	entry.Logln(PanicLevel, args...)
+}
+
+// Sprintlnn => Sprint no newline. This is to get the behavior of how
+// fmt.Sprintln where spaces are always added between operands, regardless of
+// their type. Instead of vendoring the Sprintln implementation to spare a
+// string allocation, we do the simplest thing.
+func (entry *Entry) sprintlnn(args ...interface{}) string {
+	msg := fmt.Sprintln(args...)
+	return msg[:len(msg)-1]
+}