initial commit

Dockerfile.backend

@@ -0,0 +1,22 @@
+FROM golang:1.19.1 AS builder
+
+### Copy Go code
+WORKDIR /src/
+COPY . .
+
+### Build executables
+RUN go build -o /app/webapi ./cmd/webapi
+
+
+### Create final container
+FROM debian:bullseye
+
+### Inform Docker about which port is used
+EXPOSE 3000 4000
+
+### Copy the build executable from the builder image
+WORKDIR /app/
+COPY --from=builder /app/webapi ./
+
+### Executable command
+CMD ["/app/webapi"]

Dockerfile.frontend

@@ -0,0 +1,8 @@
+FROM node:lts as builder
+WORKDIR /app
+COPY webui webui
+WORKDIR /app/webui
+RUN yarn run build-prod
+
+FROM nginx:stable
+COPY --from=builder /app/webui/dist /usr/share/nginx/html

LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2022 Enrico Bassetti
+
+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.

README.md

@@ -0,0 +1,115 @@
+# Fantastic coffee (decaffeinated)
+
+This repository contains the basic structure for [Web and Software Architecture](http://gamificationlab.uniroma1.it/en/wasa/) homework project.
+It has been described in class.
+
+"Fantastic coffee (decaffeinated)" is a simplified version for the WASA course, not suitable for a production environment.
+The full version can be found in the "Fantastic Coffee" repository.
+
+## Project structure
+
+* `cmd/` contains all executables; Go programs here should only do "executable-stuff", like reading options from the CLI/env, etc.
+	* `cmd/healthcheck` is an example of a daemon for checking the health of servers daemons; useful when the hypervisor is not providing HTTP readiness/liveness probes (e.g., Docker engine)
+	* `cmd/webapi` contains an example of a web API server daemon
+* `demo/` contains a demo config file
+* `doc/` contains the documentation (usually, for APIs, this means an OpenAPI file)
+* `service/` has all packages for implementing project-specific functionalities
+	* `service/api` contains an example of an API server
+	* `service/globaltime` contains a wrapper package for `time.Time` (useful in unit testing)
+* `vendor/` is managed by Go, and contains a copy of all dependencies
+* `webui/` is an example of a web frontend in Vue.js; it includes:
+	* Bootstrap JavaScript framework
+	* a customized version of "Bootstrap dashboard" template
+	* feather icons as SVG
+	* Go code for release embedding
+
+Other project files include:
+* `open-node.sh` starts a new (temporary) container using `node:20` image for safe and secure web frontend development (you don't want to use `node` in your system, do you?).
+
+## Go vendoring
+
+This project uses [Go Vendoring](https://go.dev/ref/mod#vendoring). You must use `go mod vendor` after changing some dependency (`go get` or `go mod tidy`) and add all files under `vendor/` directory in your commit.
+
+For more information about vendoring:
+
+* https://go.dev/ref/mod#vendoring
+* https://www.ardanlabs.com/blog/2020/04/modules-06-vendoring.html
+
+## Node/YARN vendoring
+
+This repository uses `yarn` and a vendoring technique that exploits the ["Offline mirror"](https://yarnpkg.com/features/caching). As for the Go vendoring, the dependencies are inside the repository.
+
+You should commit the files inside the `.yarn` directory.
+
+## How to set up a new project from this template
+
+You need to:
+
+* Change the Go module path to your module path in `go.mod`, `go.sum`, and in `*.go` files around the project
+* Rewrite the API documentation `doc/api.yaml`
+* If no web frontend is expected, remove `webui` and `cmd/webapi/register-webui.go`
+* Update top/package comment inside `cmd/webapi/main.go` to reflect the actual project usage, goal, and general info
+* Update the code in `run()` function (`cmd/webapi/main.go`) to connect to databases or external resources
+* Write API code inside `service/api`, and create any further package inside `service/` (or subdirectories)
+
+## How to build
+
+If you're not using the WebUI, or if you don't want to embed the WebUI into the final executable, then:
+
+```shell
+go build ./cmd/webapi/
+```
+
+If you're using the WebUI and you want to embed it into the final executable:
+
+```shell
+./open-node.sh
+# (here you're inside the container)
+yarn run build-embed
+exit
+# (outside the container)
+go build -tags webui ./cmd/webapi/
+```
+
+## How to run (in development mode)
+
+You can launch the backend only using:
+
+```shell
+go run ./cmd/webapi/
+```
+
+If you want to launch the WebUI, open a new tab and launch:
+
+```shell
+./open-node.sh
+# (here you're inside the container)
+yarn run dev
+```
+
+## How to build for production / homework delivery
+
+```shell
+./open-node.sh
+# (here you're inside the container)
+yarn run build-prod
+```
+
+For "Web and Software Architecture" students: before committing and pushing your work for grading, please read the section below named "My build works when I use `yarn run dev`, however there is a Javascript crash in production/grading"
+
+## Known issues
+
+### My build works when I use `yarn run dev`, however there is a Javascript crash in production/grading
+
+Some errors in the code are somehow not shown in `vite` development mode. To preview the code that will be used in production/grading settings, use the following commands:
+
+```shell
+./open-node.sh
+# (here you're inside the container)
+yarn run build-prod
+yarn run preview
+```
+
+## License
+
+See [LICENSE](LICENSE).

cmd/healthcheck/healthcheck.go

@@ -0,0 +1,48 @@
+/*
+Healthcheck is a simple program that sends an HTTP request to the local host (self) to a configured port number.
+It's used in environment where you need a simple probe for health checks (e.g., an empty container in docker).
+The probe URL is http://localhost:3000/liveness . Only the port can be changed.
+
+Usage:
+
+	healthcheck [flags]
+
+The flags are:
+
+	-port <1-65535>
+		Change the port where the request is sent.
+
+Return values (exit codes):
+
+	0
+		The request was successful (HTTP 200 or HTTP 204)
+
+	> 0
+		The request was not successful (connection error or unexpected HTTP status code)
+*/
+package main
+
+import (
+	"flag"
+	"fmt"
+	"net/http"
+	"os"
+)
+
+func main() {
+	var port = flag.Int("port", 3000, "HTTP port for healthcheck")
+
+	flag.Parse()
+
+	res, err := http.Get(fmt.Sprintf("http://localhost:%d/liveness", *port))
+	if err != nil {
+		_, _ = fmt.Fprintln(os.Stderr, err.Error())
+		os.Exit(1)
+	} else if res.StatusCode != http.StatusOK && res.StatusCode != http.StatusNoContent {
+		_ = res.Body.Close()
+		_, _ = fmt.Fprintln(os.Stderr, "Healthcheck request not OK: ", res.Status)
+		os.Exit(1)
+	}
+	_ = res.Body.Close()
+	os.Exit(0)
+}

cmd/webapi/cors.go

@@ -0,0 +1,21 @@
+package main
+
+import (
+	"github.com/gorilla/handlers"
+	"net/http"
+)
+
+// applyCORSHandler applies a CORS policy to the router. CORS stands for Cross-Origin Resource Sharing: it's a security
+// feature present in web browsers that blocks JavaScript requests going across different domains if not specified in a
+// policy. This function sends the policy of this API server.
+func applyCORSHandler(h http.Handler) http.Handler {
+	return handlers.CORS(
+		handlers.AllowedHeaders([]string{
+			"x-example-header",
+		}),
+		handlers.AllowedMethods([]string{"GET", "POST", "OPTIONS", "DELETE", "PUT"}),
+		// Do not modify the CORS origin and max age, they are used in the evaluation.
+		handlers.AllowedOrigins([]string{"*"}),
+		handlers.MaxAge(1),
+	)(h)
+}

cmd/webapi/load-configuration.go

@@ -0,0 +1,70 @@
+package main
+
+import (
+	"errors"
+	"fmt"
+	"github.com/ardanlabs/conf"
+	"gopkg.in/yaml.v2"
+	"io"
+	"os"
+	"time"
+)
+
+// WebAPIConfiguration describes the web API configuration. This structure is automatically parsed by
+// loadConfiguration and values from flags, environment variable or configuration file will be loaded.
+type WebAPIConfiguration struct {
+	Config struct {
+		Path string `conf:"default:/conf/config.yml"`
+	}
+	Web struct {
+		APIHost         string        `conf:"default:0.0.0.0:3000"`
+		DebugHost       string        `conf:"default:0.0.0.0:4000"`
+		ReadTimeout     time.Duration `conf:"default:5s"`
+		WriteTimeout    time.Duration `conf:"default:5s"`
+		ShutdownTimeout time.Duration `conf:"default:5s"`
+	}
+	Debug bool
+	DB    struct {
+		Filename string `conf:"default:/tmp/decaf.db"`
+	}
+}
+
+// loadConfiguration creates a WebAPIConfiguration starting from flags, environment variables and configuration file.
+// It works by loading environment variables first, then update the config using command line flags, finally loading the
+// configuration file (specified in WebAPIConfiguration.Config.Path).
+// So, CLI parameters will override the environment, and configuration file will override everything.
+// Note that the configuration file can be specified only via CLI or environment variable.
+func loadConfiguration() (WebAPIConfiguration, error) {
+	var cfg WebAPIConfiguration
+
+	// Try to load configuration from environment variables and command line switches
+	if err := conf.Parse(os.Args[1:], "CFG", &cfg); err != nil {
+		if errors.Is(err, conf.ErrHelpWanted) {
+			usage, err := conf.Usage("CFG", &cfg)
+			if err != nil {
+				return cfg, fmt.Errorf("generating config usage: %w", err)
+			}
+			fmt.Println(usage) //nolint:forbidigo
+			return cfg, conf.ErrHelpWanted
+		}
+		return cfg, fmt.Errorf("parsing config: %w", err)
+	}
+
+	// Override values from YAML if specified and if it exists (useful in k8s/compose)
+	fp, err := os.Open(cfg.Config.Path)
+	if err != nil && !os.IsNotExist(err) {
+		return cfg, fmt.Errorf("can't read the config file, while it exists: %w", err)
+	} else if err == nil {
+		yamlFile, err := io.ReadAll(fp)
+		if err != nil {
+			return cfg, fmt.Errorf("can't read config file: %w", err)
+		}
+		err = yaml.Unmarshal(yamlFile, &cfg)
+		if err != nil {
+			return cfg, fmt.Errorf("can't unmarshal config file: %w", err)
+		}
+		_ = fp.Close()
+	}
+
+	return cfg, nil
+}

cmd/webapi/main.go

@@ -0,0 +1,184 @@
+/*
+Webapi is the executable for the main web server.
+It builds a web server around APIs from `service/api`.
+Webapi connects to external resources needed (database) and starts two web servers: the API web server, and the debug.
+Everything is served via the API web server, except debug variables (/debug/vars) and profiler infos (pprof).
+
+Usage:
+
+	webapi [flags]
+
+Flags and configurations are handled automatically by the code in `load-configuration.go`.
+
+Return values (exit codes):
+
+	0
+		The program ended successfully (no errors, stopped by signal)
+
+	> 0
+		The program ended due to an error
+
+Note that this program will update the schema of the database to the latest version available (embedded in the
+executable during the build).
+*/
+package main
+
+import (
+	"context"
+	"database/sql"
+	"errors"
+	"fmt"
+	"git.sapienzaapps.it/fantasticcoffee/fantastic-coffee-decaffeinated/service/api"
+	"git.sapienzaapps.it/fantasticcoffee/fantastic-coffee-decaffeinated/service/database"
+	"git.sapienzaapps.it/fantasticcoffee/fantastic-coffee-decaffeinated/service/globaltime"
+	"github.com/ardanlabs/conf"
+	_ "github.com/mattn/go-sqlite3"
+	"github.com/sirupsen/logrus"
+	"math/rand"
+	"net/http"
+	"os"
+	"os/signal"
+	"syscall"
+)
+
+// main is the program entry point. The only purpose of this function is to call run() and set the exit code if there is
+// any error
+func main() {
+	if err := run(); err != nil {
+		_, _ = fmt.Fprintln(os.Stderr, "error: ", err)
+		os.Exit(1)
+	}
+}
+
+// run executes the program. The body of this function should perform the following steps:
+// * reads the configuration
+// * creates and configure the logger
+// * connects to any external resources (like databases, authenticators, etc.)
+// * creates an instance of the service/api package
+// * starts the principal web server (using the service/api.Router.Handler() for HTTP handlers)
+// * waits for any termination event: SIGTERM signal (UNIX), non-recoverable server error, etc.
+// * closes the principal web server
+func run() error {
+	rand.Seed(globaltime.Now().UnixNano())
+	// Load Configuration and defaults
+	cfg, err := loadConfiguration()
+	if err != nil {
+		if errors.Is(err, conf.ErrHelpWanted) {
+			return nil
+		}
+		return err
+	}
+
+	// Init logging
+	logger := logrus.New()
+	logger.SetOutput(os.Stdout)
+	if cfg.Debug {
+		logger.SetLevel(logrus.DebugLevel)
+	} else {
+		logger.SetLevel(logrus.InfoLevel)
+	}
+
+	logger.Infof("application initializing")
+
+	// Start Database
+	logger.Println("initializing database support")
+	dbconn, err := sql.Open("sqlite3", cfg.DB.Filename)
+	if err != nil {
+		logger.WithError(err).Error("error opening SQLite DB")
+		return fmt.Errorf("opening SQLite: %w", err)
+	}
+	defer func() {
+		logger.Debug("database stopping")
+		_ = dbconn.Close()
+	}()
+	db, err := database.New(dbconn)
+	if err != nil {
+		logger.WithError(err).Error("error creating AppDatabase")
+		return fmt.Errorf("creating AppDatabase: %w", err)
+	}
+
+	// Start (main) API server
+	logger.Info("initializing API server")
+
+	// Make a channel to listen for an interrupt or terminate signal from the OS.
+	// Use a buffered channel because the signal package requires it.
+	shutdown := make(chan os.Signal, 1)
+	signal.Notify(shutdown, os.Interrupt, syscall.SIGTERM)
+
+	// Make a channel to listen for errors coming from the listener. Use a
+	// buffered channel so the goroutine can exit if we don't collect this error.
+	serverErrors := make(chan error, 1)
+
+	// Create the API router
+	apirouter, err := api.New(api.Config{
+		Logger:   logger,
+		Database: db,
+	})
+	if err != nil {
+		logger.WithError(err).Error("error creating the API server instance")
+		return fmt.Errorf("creating the API server instance: %w", err)
+	}
+	router := apirouter.Handler()
+
+	router, err = registerWebUI(router)
+	if err != nil {
+		logger.WithError(err).Error("error registering web UI handler")
+		return fmt.Errorf("registering web UI handler: %w", err)
+	}
+
+	// Apply CORS policy
+	router = applyCORSHandler(router)
+
+	// Create the API server
+	apiserver := http.Server{
+		Addr:              cfg.Web.APIHost,
+		Handler:           router,
+		ReadTimeout:       cfg.Web.ReadTimeout,
+		ReadHeaderTimeout: cfg.Web.ReadTimeout,
+		WriteTimeout:      cfg.Web.WriteTimeout,
+	}
+
+	// Start the service listening for requests in a separate goroutine
+	go func() {
+		logger.Infof("API listening on %s", apiserver.Addr)
+		serverErrors <- apiserver.ListenAndServe()
+		logger.Infof("stopping API server")
+	}()
+
+	// Waiting for shutdown signal or POSIX signals
+	select {
+	case err := <-serverErrors:
+		// Non-recoverable server error
+		return fmt.Errorf("server error: %w", err)
+
+	case sig := <-shutdown:
+		logger.Infof("signal %v received, start shutdown", sig)
+
+		// Asking API server to shut down and load shed.
+		err := apirouter.Close()
+		if err != nil {
+			logger.WithError(err).Warning("graceful shutdown of apirouter error")
+		}
+
+		// Give outstanding requests a deadline for completion.
+		ctx, cancel := context.WithTimeout(context.Background(), cfg.Web.ShutdownTimeout)
+		defer cancel()
+
+		// Asking listener to shut down and load shed.
+		err = apiserver.Shutdown(ctx)
+		if err != nil {
+			logger.WithError(err).Warning("error during graceful shutdown of HTTP server")
+			err = apiserver.Close()
+		}
+
+		// Log the status of this shutdown.
+		switch {
+		case sig == syscall.SIGSTOP:
+			return errors.New("integrity issue caused shutdown")
+		case err != nil:
+			return fmt.Errorf("could not stop server gracefully: %w", err)
+		}
+	}
+
+	return nil
+}

cmd/webapi/register-web-ui-stub.go

@@ -0,0 +1,12 @@
+//go:build !webui
+
+package main
+
+import (
+	"net/http"
+)
+
+// registerWebUI is an empty stub because `webui` tag has not been specified.
+func registerWebUI(hdl http.Handler) (http.Handler, error) {
+	return hdl, nil
+}

cmd/webapi/register-web-ui.go

@@ -0,0 +1,25 @@
+//go:build webui
+
+package main
+
+import (
+	"fmt"
+	"git.sapienzaapps.it/fantasticcoffee/fantastic-coffee-decaffeinated/webui"
+	"io/fs"
+	"net/http"
+	"strings"
+)
+
+func registerWebUI(hdl http.Handler) (http.Handler, error) {
+	distDirectory, err := fs.Sub(webui.Dist, "dist")
+	if err != nil {
+		return nil, fmt.Errorf("error embedding WebUI dist/ directory: %w", err)
+	}
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if strings.HasPrefix(r.RequestURI, "/dashboard/") {
+			http.StripPrefix("/dashboard/", http.FileServer(http.FS(distDirectory))).ServeHTTP(w, r)
+			return
+		}
+		hdl.ServeHTTP(w, r)
+	}), nil
+}

demo/config.yml

@@ -0,0 +1,17 @@
+# This is the configuration file for the API service
+# Description of this part is present in the `main.go` file
+
+log:
+  level: debug
+#  methodname: false
+#  json: false
+#  destination: stderr
+#  file: /tmp/debug.log
+#  combinedtostdout: true
+#web:
+#  apihost: 0.0.0.0:3000
+#  debughost: 0.0.0.0:4000
+#  readtimeout: 5s
+#  writetimeout: 5s
+#  shutdowntimeout: 5s
+#  behindproxy: false

doc/api.yaml

@@ -0,0 +1,273 @@
+openapi: 3.0.0
+servers:
+  - url: "http://localhost:3000"
+info:
+  title: Fantastic Coffee (decaffeinated)
+  description: Fantastic Coffee (decaffeinated), the skeleton project for Web and Software architecture course
+  version: 1.0.0
+paths:
+  /status:
+    parameters:
+      - $ref: "#/components/parameters/XAppBuild"
+      - $ref: "#/components/parameters/XAppVersion"
+      - $ref: "#/components/parameters/XAppLanguage"
+      - $ref: "#/components/parameters/XAppPlatform"
+    get:
+      tags: ["General"]
+      operationId: getStatusMessage
+      summary: Get status message for the user about issues / updates
+      description: |-
+        The response contains a status message meant for the user. It might
+        contains information about current technical issues, update messages
+        or general information.
+      responses:
+        "200":
+          description: Status message available
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/StatusInfo"
+        "400": { $ref: "#/components/responses/BadRequest" }
+        "500": { $ref: "#/components/responses/InternalServerError" }
+
+  /:
+    get:
+      tags: ["Group 1"]
+      operationId: index
+      summary: Get an index
+      description: |-
+        This is an example of an index API description
+      responses:
+        "200":
+          description: Successful
+        "400": { $ref: "#/components/responses/BadRequest" }
+        "500": { $ref: "#/components/responses/InternalServerError" }
+  /context:
+    parameters:
+      - $ref: "#/components/parameters/XAppBuild"
+      - $ref: "#/components/parameters/XAppVersion"
+      - $ref: "#/components/parameters/XAppLanguage"
+      - $ref: "#/components/parameters/XAppPlatform"
+    post:
+      tags: ["Group 1"]
+      operationId: getContext
+      summary: Another API example
+      description: |-
+        Example description 2
+      responses:
+        "200":
+          description: Request ok
+          headers:
+            X-Access-Token:
+              description: Access token for authenticated requests
+              schema: { type: string }
+        "500": { $ref: "#/components/responses/InternalServerError" }
+  /authenticated:
+    parameters:
+      - $ref: "#/components/parameters/XAppBuild"
+      - $ref: "#/components/parameters/XAppVersion"
+      - $ref: "#/components/parameters/XAppLanguage"
+      - $ref: "#/components/parameters/XAppPlatform"
+    get:
+      tags: ["Group 2"]
+      operationId: getAuthenticatedExample
+      summary: Get an endpoint with authentication
+      description: |-
+        Get an endpoint with auth
+      security:
+        - LegacyAuth: []
+        - AppToken: []
+      responses:
+        "200":
+          description: Logout successful
+        "500": { $ref: "#/components/responses/InternalServerError" }
+
+  /pictures/{cat}:
+    parameters:
+      - $ref: "#/components/parameters/XAppBuild"
+      - $ref: "#/components/parameters/XAppVersion"
+      - $ref: "#/components/parameters/XAppLanguage"
+      - $ref: "#/components/parameters/XAppPlatform"
+      - $ref: "#/components/parameters/cat"
+    get:
+      tags: ["Cat pictures"]
+      operationId: getCatFromPicture
+      summary: Example of a parameter in URL
+      description: |-
+        Example of a parameter in URL
+      security:
+        - LegacyAuth: []
+      responses:
+        "200":
+          description: Student picture found
+          content:
+            image/png:
+              schema:
+                type: string
+                format: binary
+              example: Picture binary file
+        "404":
+          description: Student picture not found
+        "500": { $ref: "#/components/responses/InternalServerError" }
+
+
+  /autofeeder/{cat}:
+    parameters:
+      - $ref: "#/components/parameters/XAppBuild"
+      - $ref: "#/components/parameters/XAppVersion"
+      - $ref: "#/components/parameters/XAppLanguage"
+      - $ref: "#/components/parameters/XAppPlatform"
+      - $ref: "#/components/parameters/cat"
+    put:
+      tags: ["Autofeeder"]
+      operationId: createCatAutofeeder
+      summary: Example of PUT operation
+      security:
+        - LegacyAuth: []
+      responses:
+        "200":
+          description: Auto feed enabled
+        "400": { $ref: "#/components/responses/BadRequest" }
+        "500": { $ref: "#/components/responses/InternalServerError" }
+    delete:
+      tags: ["Autofeeder"]
+      operationId: deleteCatAutofeeder
+      summary: Example of DELETE operation
+      security:
+        - LegacyAuth: []
+      responses:
+        "200":
+          description: Auto feed disabled
+        "400": { $ref: "#/components/responses/BadRequest" }
+        "500": { $ref: "#/components/responses/InternalServerError" }
+
+  /session/login:
+    parameters:
+      - $ref: "#/components/parameters/XAppBuild"
+      - $ref: "#/components/parameters/XAppVersion"
+      - $ref: "#/components/parameters/XAppLanguage"
+      - $ref: "#/components/parameters/XAppPlatform"
+    post:
+      tags: ["Session management"]
+      operationId: login
+      summary: Log-in into system
+      description: |-
+        Perform a log-in action using username and password credentials.
+        Returns a token which can be used in authenticated requests.
+      requestBody:
+        content:
+          application/x-www-form-urlencoded:
+            schema:
+              type: object
+              properties:
+                userid:
+                  type: string
+                  pattern: '^[a-zA-Z0-9]+$'
+                  minLength: 3
+                  maxLength: 255
+                password:
+                  type: string
+                  pattern: '^.*?$'
+                  minLength: 8
+                  maxLength: 255
+      responses:
+        "200":
+          description: Login successful
+          headers:
+            X-Access-Token:
+              description: Access token for authenticated requests
+              schema: { type: string }
+        "400": { $ref: "#/components/responses/BadRequest" }
+        "403":
+          description: Login failed
+          headers:
+            X-Message:
+              description: Error message
+              schema: { type: string }
+        "500": { $ref: "#/components/responses/InternalServerError" }
+
+
+components:
+  schemas:
+    StatusInfo:
+      title: Status Info
+      type: object
+      properties:
+        status:
+          type: string
+          enum:
+            - info
+            - warning
+            - critical
+            - ""
+        title: { type: string }
+        message: { type: string }
+        url: { type: string }
+
+  responses:
+    Unauthorized:
+      description: The access token is missing or it's expired
+    BadRequest:
+      description: The request was not compliant with the documentation (eg. missing fields, etc)
+    InternalServerError:
+      description: The server encountered an internal error. Further info in server logs
+
+  securitySchemes:
+    LegacyAuth:
+      type: apiKey
+      in: header
+      name: X-App-Token
+      description: |-
+        App session token value. This value is sent by the server in the login
+        and session refresh APIs.
+
+  parameters:
+    XAppVersion:
+      schema:
+        type: string
+        pattern: '^(0|[1-9]\d*)\.(0|[1-9]\d*)\.(0|[1-9]\d*)(?:-((?:0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*)(?:\.(?:0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*))*))?(?:\+([0-9a-zA-Z-]+(?:\.[0-9a-zA-Z-]+)*))?$'
+        minLength: 1
+        maxLength: 10
+      name: X-App-Version
+      in: header
+      required: true
+      description: App human readable version ("semantic version" format)
+      allowEmptyValue: false
+    XAppBuild:
+      schema: { type: integer }
+      name: X-App-Build
+      in: header
+      required: true
+      description: App build number
+      allowEmptyValue: false
+    XAppLanguage:
+      schema:
+        type: string
+        pattern: '^[a-z]{2}([-_][A-Z]{2})?$'
+        minLength: 2
+        maxLength: 5
+      name: X-App-Language
+      in: header
+      required: true
+      description: App language in ISO 639-1 format
+      allowEmptyValue: false
+    XAppPlatform:
+      schema:
+        type: string
+        enum: [ios, android]
+      name: X-App-Platform
+      in: header
+      required: true
+      description: App operating system / platform
+      allowEmptyValue: false
+    cat:
+      schema:
+        type: string
+        pattern: '^[a-zA-Z]+$'
+        minLength: 3
+        maxLength: 10
+      name: cat
+      in: path
+      required: true
+      description: Cat
+      allowEmptyValue: false

go.mod

@@ -0,0 +1,22 @@
+module git.sapienzaapps.it/fantasticcoffee/fantastic-coffee-decaffeinated
+
+go 1.17
+
+require (
+	github.com/ardanlabs/conf v1.5.0
+	github.com/gofrs/uuid v4.4.0+incompatible
+	github.com/gorilla/handlers v1.5.2
+	github.com/julienschmidt/httprouter v1.3.0
+	github.com/mattn/go-sqlite3 v1.14.23
+	github.com/sirupsen/logrus v1.9.3
+	gopkg.in/yaml.v2 v2.4.0
+)
+
+require (
+	github.com/felixge/httpsnoop v1.0.4 // indirect
+	github.com/google/go-cmp v0.5.8 // indirect
+	github.com/kr/pretty v0.1.0 // indirect
+	golang.org/x/sys v0.25.0 // indirect
+	gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15 // indirect
+	gopkg.in/yaml.v3 v3.0.0-20210107192922-496545a6307b // indirect
+)

go.sum

@@ -0,0 +1,41 @@
+github.com/ardanlabs/conf v1.5.0 h1:5TwP6Wu9Xi07eLFEpiCUF3oQXh9UzHMDVnD3u/I5d5c=
+github.com/ardanlabs/conf v1.5.0/go.mod h1:ILsMo9dMqYzCxDjDXTiwMI0IgxOJd0MOiucbQY2wlJw=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/felixge/httpsnoop v1.0.4 h1:NFTV2Zj1bL4mc9sqWACXbQFVBBg2W3GPvqp8/ESS2Wg=
+github.com/felixge/httpsnoop v1.0.4/go.mod h1:m8KPJKqk1gH5J9DgRY2ASl2lWCfGKXixSwevea8zH2U=
+github.com/gofrs/uuid v4.4.0+incompatible h1:3qXRTX8/NbyulANqlc0lchS1gqAVxRgsuW1YrTJupqA=
+github.com/gofrs/uuid v4.4.0+incompatible/go.mod h1:b2aQJv3Z4Fp6yNu3cdSllBxTCLRxnplIgP/c0N/04lM=
+github.com/google/go-cmp v0.3.1/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
+github.com/google/go-cmp v0.5.8 h1:e6P7q2lk1O+qJJb4BtCQXlK8vWEO8V1ZeuEdJNOqZyg=
+github.com/google/go-cmp v0.5.8/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
+github.com/gorilla/handlers v1.5.2 h1:cLTUSsNkgcwhgRqvCNmdbRWG0A3N4F+M2nWKdScwyEE=
+github.com/gorilla/handlers v1.5.2/go.mod h1:dX+xVpaxdSw+q0Qek8SSsl3dfMk3jNddUkMzo0GtH0w=
+github.com/julienschmidt/httprouter v1.3.0 h1:U0609e9tgbseu3rBINet9P48AI/D3oJs4dN7jwJOQ1U=
+github.com/julienschmidt/httprouter v1.3.0/go.mod h1:JR6WtHb+2LUe8TCKY3cZOxFyyO8IZAc4RVcycCCAKdM=
+github.com/kr/pretty v0.1.0 h1:L/CwN0zerZDmRFUapSPitk6f+Q3+0za1rQkzVuMiMFI=
+github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
+github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
+github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
+github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
+github.com/mattn/go-sqlite3 v1.14.23 h1:gbShiuAP1W5j9UOksQ06aiiqPMxYecovVGwmTxWtuw0=
+github.com/mattn/go-sqlite3 v1.14.23/go.mod h1:Uh1q+B4BYcTPb+yiD3kU8Ct7aC0hY9fxUwlHK0RXw+Y=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/sirupsen/logrus v1.9.3 h1:dueUQJ1C2q9oE3F7wvmSGAaVtTmUizReu6fjN8uqzbQ=
+github.com/sirupsen/logrus v1.9.3/go.mod h1:naHLuLoDiP4jHNo9R0sCBMtWGeIprob74mVsIT4qYEQ=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/testify v1.7.0 h1:nwc3DEeHmmLAfoZucVR881uASk0Mfjw8xYJ99tb5CcY=
+github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+golang.org/x/sys v0.0.0-20220715151400-c0bba94af5f8/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.25.0 h1:r+8e+loiHxRqhXVl6ML1nO3l1+oFoWbnlu2Ehimmi34=
+golang.org/x/sys v0.25.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15 h1:YR8cESwS4TdDjEe65xsg0ogRM/Nc3DYOhEAlW+xobZo=
+gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v2 v2.4.0 h1:D8xgwECY7CYvx+Y2n4sBz93Jn9JRvxdiyyo8CTfuKaY=
+gopkg.in/yaml.v2 v2.4.0/go.mod h1:RDklbk79AGWmwhnvt/jBztapEOGDOx6ZbXqjP6csGnQ=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gopkg.in/yaml.v3 v3.0.0-20210107192922-496545a6307b h1:h8qDotaEPuJATrMmW04NCwg7v22aHH28wwpauUhK9Oo=
+gopkg.in/yaml.v3 v3.0.0-20210107192922-496545a6307b/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

open-node.sh

@@ -0,0 +1,3 @@
+#!/usr/bin/env sh
+
+docker run -it --rm -v "$(pwd):/src" -u "$(id -u):$(id -g)" --network host --workdir /src/webui node:20 /bin/bash

service/api/api-context-wrapper.go

@@ -0,0 +1,37 @@
+package api
+
+import (
+	"git.sapienzaapps.it/fantasticcoffee/fantastic-coffee-decaffeinated/service/api/reqcontext"
+	"github.com/gofrs/uuid"
+	"github.com/julienschmidt/httprouter"
+	"github.com/sirupsen/logrus"
+	"net/http"
+)
+
+// httpRouterHandler is the signature for functions that accepts a reqcontext.RequestContext in addition to those
+// required by the httprouter package.
+type httpRouterHandler func(http.ResponseWriter, *http.Request, httprouter.Params, reqcontext.RequestContext)
+
+// wrap parses the request and adds a reqcontext.RequestContext instance related to the request.
+func (rt *_router) wrap(fn httpRouterHandler) func(http.ResponseWriter, *http.Request, httprouter.Params) {
+	return func(w http.ResponseWriter, r *http.Request, ps httprouter.Params) {
+		reqUUID, err := uuid.NewV4()
+		if err != nil {
+			rt.baseLogger.WithError(err).Error("can't generate a request UUID")
+			w.WriteHeader(http.StatusInternalServerError)
+			return
+		}
+		var ctx = reqcontext.RequestContext{
+			ReqUUID: reqUUID,
+		}
+
+		// Create a request-specific logger
+		ctx.Logger = rt.baseLogger.WithFields(logrus.Fields{
+			"reqid":     ctx.ReqUUID.String(),
+			"remote-ip": r.RemoteAddr,
+		})
+
+		// Call the next handler in chain (usually, the handler function for the path)
+		fn(w, r, ps, ctx)
+	}
+}

service/api/api-handler.go

@@ -0,0 +1,17 @@
+package api
+
+import (
+	"net/http"
+)
+
+// Handler returns an instance of httprouter.Router that handle APIs registered here
+func (rt *_router) Handler() http.Handler {
+	// Register routes
+	rt.router.GET("/", rt.getHelloWorld)
+	rt.router.GET("/context", rt.wrap(rt.getContextReply))
+
+	// Special routes
+	rt.router.GET("/liveness", rt.liveness)
+
+	return rt.router
+}

service/api/api.go

@@ -0,0 +1,96 @@
+/*
+Package api exposes the main API engine. All HTTP APIs are handled here - so-called "business logic" should be here, or
+in a dedicated package (if that logic is complex enough).
+
+To use this package, you should create a new instance with New() passing a valid Config. The resulting Router will have
+the Router.Handler() function that returns a handler that can be used in a http.Server (or in other middlewares).
+
+Example:
+
+	// Create the API router
+	apirouter, err := api.New(api.Config{
+		Logger:   logger,
+		Database: appdb,
+	})
+	if err != nil {
+		logger.WithError(err).Error("error creating the API server instance")
+		return fmt.Errorf("error creating the API server instance: %w", err)
+	}
+	router := apirouter.Handler()
+
+	// ... other stuff here, like middleware chaining, etc.
+
+	// Create the API server
+	apiserver := http.Server{
+		Addr:              cfg.Web.APIHost,
+		Handler:           router,
+		ReadTimeout:       cfg.Web.ReadTimeout,
+		ReadHeaderTimeout: cfg.Web.ReadTimeout,
+		WriteTimeout:      cfg.Web.WriteTimeout,
+	}
+
+	// Start the service listening for requests in a separate goroutine
+	apiserver.ListenAndServe()
+
+See the `main.go` file inside the `cmd/webapi` for a full usage example.
+*/
+package api
+
+import (
+	"errors"
+	"git.sapienzaapps.it/fantasticcoffee/fantastic-coffee-decaffeinated/service/database"
+	"github.com/julienschmidt/httprouter"
+	"github.com/sirupsen/logrus"
+	"net/http"
+)
+
+// Config is used to provide dependencies and configuration to the New function.
+type Config struct {
+	// Logger where log entries are sent
+	Logger logrus.FieldLogger
+
+	// Database is the instance of database.AppDatabase where data are saved
+	Database database.AppDatabase
+}
+
+// Router is the package API interface representing an API handler builder
+type Router interface {
+	// Handler returns an HTTP handler for APIs provided in this package
+	Handler() http.Handler
+
+	// Close terminates any resource used in the package
+	Close() error
+}
+
+// New returns a new Router instance
+func New(cfg Config) (Router, error) {
+	// Check if the configuration is correct
+	if cfg.Logger == nil {
+		return nil, errors.New("logger is required")
+	}
+	if cfg.Database == nil {
+		return nil, errors.New("database is required")
+	}
+
+	// Create a new router where we will register HTTP endpoints. The server will pass requests to this router to be
+	// handled.
+	router := httprouter.New()
+	router.RedirectTrailingSlash = false
+	router.RedirectFixedPath = false
+
+	return &_router{
+		router:     router,
+		baseLogger: cfg.Logger,
+		db:         cfg.Database,
+	}, nil
+}
+
+type _router struct {
+	router *httprouter.Router
+
+	// baseLogger is a logger for non-requests contexts, like goroutines or background tasks not started by a request.
+	// Use context logger if available (e.g., in requests) instead of this logger.
+	baseLogger logrus.FieldLogger
+
+	db database.AppDatabase
+}

service/api/get-context-reply.go

@@ -0,0 +1,14 @@
+package api
+
+import (
+	"git.sapienzaapps.it/fantasticcoffee/fantastic-coffee-decaffeinated/service/api/reqcontext"
+	"github.com/julienschmidt/httprouter"
+	"net/http"
+)
+
+// getContextReply is an example of HTTP endpoint that returns "Hello World!" as a plain text. The signature of this
+// handler accepts a reqcontext.RequestContext (see httpRouterHandler).
+func (rt *_router) getContextReply(w http.ResponseWriter, r *http.Request, ps httprouter.Params, ctx reqcontext.RequestContext) {
+	w.Header().Set("content-type", "text/plain")
+	_, _ = w.Write([]byte("Hello World!"))
+}

service/api/get-hello-world.go

@@ -0,0 +1,12 @@
+package api
+
+import (
+	"github.com/julienschmidt/httprouter"
+	"net/http"
+)
+
+// getHelloWorld is an example of HTTP endpoint that returns "Hello world!" as a plain text
+func (rt *_router) getHelloWorld(w http.ResponseWriter, r *http.Request, ps httprouter.Params) {
+	w.Header().Set("content-type", "text/plain")
+	_, _ = w.Write([]byte("Hello World!"))
+}

service/api/liveness.go

@@ -0,0 +1,16 @@
+package api
+
+import (
+	"github.com/julienschmidt/httprouter"
+	"net/http"
+)
+
+// liveness is an HTTP handler that checks the API server status. If the server cannot serve requests (e.g., some
+// resources are not ready), this should reply with HTTP Status 500. Otherwise, with HTTP Status 200
+func (rt *_router) liveness(w http.ResponseWriter, r *http.Request, ps httprouter.Params) {
+	/* Example of liveness check:
+	if err := rt.DB.Ping(); err != nil {
+		w.WriteHeader(http.StatusInternalServerError)
+		return
+	}*/
+}

service/api/reqcontext/request-context.go

@@ -0,0 +1,21 @@
+/*
+Package reqcontext contains the request context. Each request will have its own instance of RequestContext filled by the
+middleware code in the api-context-wrapper.go (parent package).
+
+Each value here should be assumed valid only per request only, with some exceptions like the logger.
+*/
+package reqcontext
+
+import (
+	"github.com/gofrs/uuid"
+	"github.com/sirupsen/logrus"
+)
+
+// RequestContext is the context of the request, for request-dependent parameters
+type RequestContext struct {
+	// ReqUUID is the request unique ID
+	ReqUUID uuid.UUID
+
+	// Logger is a custom field logger for the request
+	Logger logrus.FieldLogger
+}

service/api/shutdown.go

@@ -0,0 +1,6 @@
+package api
+
+// Close should close everything opened in the lifecycle of the `_router`; for example, background goroutines.
+func (rt *_router) Close() error {
+	return nil
+}

service/database/database.go

@@ -0,0 +1,76 @@
+/*
+Package database is the middleware between the app database and the code. All data (de)serialization (save/load) from a
+persistent database are handled here. Database specific logic should never escape this package.
+
+To use this package you need to apply migrations to the database if needed/wanted, connect to it (using the database
+data source name from config), and then initialize an instance of AppDatabase from the DB connection.
+
+For example, this code adds a parameter in `webapi` executable for the database data source name (add it to the
+main.WebAPIConfiguration structure):
+
+	DB struct {
+		Filename string `conf:""`
+	}
+
+This is an example on how to migrate the DB and connect to it:
+
+	// Start Database
+	logger.Println("initializing database support")
+	db, err := sql.Open("sqlite3", "./foo.db")
+	if err != nil {
+		logger.WithError(err).Error("error opening SQLite DB")
+		return fmt.Errorf("opening SQLite: %w", err)
+	}
+	defer func() {
+		logger.Debug("database stopping")
+		_ = db.Close()
+	}()
+
+Then you can initialize the AppDatabase and pass it to the api package.
+*/
+package database
+
+import (
+	"database/sql"
+	"errors"
+	"fmt"
+)
+
+// AppDatabase is the high level interface for the DB
+type AppDatabase interface {
+	GetName() (string, error)
+	SetName(name string) error
+
+	Ping() error
+}
+
+type appdbimpl struct {
+	c *sql.DB
+}
+
+// New returns a new instance of AppDatabase based on the SQLite connection `db`.
+// `db` is required - an error will be returned if `db` is `nil`.
+func New(db *sql.DB) (AppDatabase, error) {
+	if db == nil {
+		return nil, errors.New("database is required when building a AppDatabase")
+	}
+
+	// Check if table exists. If not, the database is empty, and we need to create the structure
+	var tableName string
+	err := db.QueryRow(`SELECT name FROM sqlite_master WHERE type='table' AND name='example_table';`).Scan(&tableName)
+	if errors.Is(err, sql.ErrNoRows) {
+		sqlStmt := `CREATE TABLE example_table (id INTEGER NOT NULL PRIMARY KEY, name TEXT);`
+		_, err = db.Exec(sqlStmt)
+		if err != nil {
+			return nil, fmt.Errorf("error creating database structure: %w", err)
+		}
+	}
+
+	return &appdbimpl{
+		c: db,
+	}, nil
+}
+
+func (db *appdbimpl) Ping() error {
+	return db.c.Ping()
+}

service/database/get-name.go

@@ -0,0 +1,8 @@
+package database
+
+// GetName is an example that shows you how to query data
+func (db *appdbimpl) GetName() (string, error) {
+	var name string
+	err := db.c.QueryRow("SELECT name FROM example_table WHERE id=1").Scan(&name)
+	return name, err
+}

service/database/set-name.go

@@ -0,0 +1,7 @@
+package database
+
+// SetName is an example that shows you how to execute insert/update
+func (db *appdbimpl) SetName(name string) error {
+	_, err := db.c.Exec("INSERT INTO example_table (id, name) VALUES (1, ?)", name)
+	return err
+}

service/globaltime/globaltime.go

@@ -0,0 +1,21 @@
+package globaltime
+
+import "time"
+
+// FixedTime represent a fixed moment in time. Set this variable to anything different from the default value for
+// time.Time and the value will be returned in Now() function in place of the current time
+var FixedTime time.Time
+
+// Now returns the current time (time.Now()) if no FixedTime has been set. Otherwise, it returns FixedTime.
+// Use this in place of time.Now() to allow testing w/ custom time.
+func Now() time.Time {
+	if FixedTime.After(time.Time{}) {
+		return FixedTime
+	}
+	return time.Now()
+}
+
+// Since returns the time passed since the parameter tm.
+func Since(tm time.Time) time.Duration {
+	return Now().Sub(tm)
+}

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
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
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+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
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+      including but not limited to software source code, documentation
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+
+      "Work" shall mean the work of authorship, whether in Source or
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+      "Derivative Works" shall mean any work, whether in Source or Object
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+      to the Licensor or its representatives, including but not limited to
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+          notices within Derivative Works that You distribute, alongside
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+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
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+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
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+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
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+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
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+      Work (including but not limited to damages for loss of goodwill,
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+      and charge a fee for, acceptance of support, warranty, indemnity,
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+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
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+      file or class name and description of purpose be included on the
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+
+   Copyright [yyyy] [name of copyright owner]
+
+   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.

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/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 -race -v ./...
+
+generate:
+	go generate .
+
+clean:
+	rm -rf *_generated*.go

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

@@ -0,0 +1,95 @@
+# 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.
+
+[![Go Reference](https://pkg.go.dev/badge/github.com/felixge/httpsnoop.svg)](https://pkg.go.dev/github.com/felixge/httpsnoop)
+[![Build Status](https://github.com/felixge/httpsnoop/actions/workflows/main.yaml/badge.svg)](https://github.com/felixge/httpsnoop/actions/workflows/main.yaml)
+
+## 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. You can however use `httpsnoop.Unwrap(w)` to access the underlying
+`http.ResponseWriter` and type-assert the result to its other interfaces.
+
+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 +1,86 @@
+package httpsnoop
+
+import (
+	"io"
+	"net/http"
+	"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 {
+	m := Metrics{Code: http.StatusOK}
+	m.CaptureMetrics(w, fn)
+	return m
+}
+
+// CaptureMetrics wraps w and calls fn with the wrapped w and updates
+// Metrics m with the resulting metrics. This is similar to CaptureMetricsFn,
+// but allows one to customize starting Metrics object.
+func (m *Metrics) CaptureMetrics(w http.ResponseWriter, fn func(http.ResponseWriter)) {
+	var (
+		start         = time.Now()
+		headerWritten bool
+		hooks         = Hooks{
+			WriteHeader: func(next WriteHeaderFunc) WriteHeaderFunc {
+				return func(code int) {
+					next(code)
+
+					if !(code >= 100 && code <= 199) && !headerWritten {
+						m.Code = code
+						headerWritten = true
+					}
+				}
+			},
+
+			Write: func(next WriteFunc) WriteFunc {
+				return func(p []byte) (int, error) {
+					n, err := next(p)
+
+					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)
+
+					headerWritten = true
+					m.Written += n
+					return n, err
+				}
+			},
+		}
+	)
+
+	fn(Wrap(w, hooks))
+	m.Duration += time.Since(start)
+}

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 +1,436 @@
+// +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 {
+			Unwrapper
+			http.ResponseWriter
+		}{rw, rw}
+	// combination 2/32
+	case !i0 && !i1 && !i2 && !i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Pusher
+		}{rw, rw, rw}
+	// combination 3/32
+	case !i0 && !i1 && !i2 && i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			io.ReaderFrom
+		}{rw, rw, rw}
+	// combination 4/32
+	case !i0 && !i1 && !i2 && i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			io.ReaderFrom
+			http.Pusher
+		}{rw, rw, rw, rw}
+	// combination 5/32
+	case !i0 && !i1 && i2 && !i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Hijacker
+		}{rw, rw, rw}
+	// combination 6/32
+	case !i0 && !i1 && i2 && !i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Hijacker
+			http.Pusher
+		}{rw, rw, rw, rw}
+	// combination 7/32
+	case !i0 && !i1 && i2 && i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Hijacker
+			io.ReaderFrom
+		}{rw, rw, rw, rw}
+	// combination 8/32
+	case !i0 && !i1 && i2 && i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Hijacker
+			io.ReaderFrom
+			http.Pusher
+		}{rw, rw, rw, rw, rw}
+	// combination 9/32
+	case !i0 && i1 && !i2 && !i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.CloseNotifier
+		}{rw, rw, rw}
+	// combination 10/32
+	case !i0 && i1 && !i2 && !i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.CloseNotifier
+			http.Pusher
+		}{rw, rw, rw, rw}
+	// combination 11/32
+	case !i0 && i1 && !i2 && i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.CloseNotifier
+			io.ReaderFrom
+		}{rw, rw, rw, rw}
+	// combination 12/32
+	case !i0 && i1 && !i2 && i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.CloseNotifier
+			io.ReaderFrom
+			http.Pusher
+		}{rw, rw, rw, rw, rw}
+	// combination 13/32
+	case !i0 && i1 && i2 && !i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.CloseNotifier
+			http.Hijacker
+		}{rw, rw, rw, rw}
+	// combination 14/32
+	case !i0 && i1 && i2 && !i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.CloseNotifier
+			http.Hijacker
+			http.Pusher
+		}{rw, rw, rw, rw, rw}
+	// combination 15/32
+	case !i0 && i1 && i2 && i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.CloseNotifier
+			http.Hijacker
+			io.ReaderFrom
+		}{rw, rw, rw, rw, rw}
+	// combination 16/32
+	case !i0 && i1 && i2 && i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.CloseNotifier
+			http.Hijacker
+			io.ReaderFrom
+			http.Pusher
+		}{rw, rw, rw, rw, rw, rw}
+	// combination 17/32
+	case i0 && !i1 && !i2 && !i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+		}{rw, rw, rw}
+	// combination 18/32
+	case i0 && !i1 && !i2 && !i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.Pusher
+		}{rw, rw, rw, rw}
+	// combination 19/32
+	case i0 && !i1 && !i2 && i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			io.ReaderFrom
+		}{rw, rw, rw, rw}
+	// combination 20/32
+	case i0 && !i1 && !i2 && i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			io.ReaderFrom
+			http.Pusher
+		}{rw, rw, rw, rw, rw}
+	// combination 21/32
+	case i0 && !i1 && i2 && !i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.Hijacker
+		}{rw, rw, rw, rw}
+	// combination 22/32
+	case i0 && !i1 && i2 && !i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.Hijacker
+			http.Pusher
+		}{rw, rw, rw, rw, rw}
+	// combination 23/32
+	case i0 && !i1 && i2 && i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.Hijacker
+			io.ReaderFrom
+		}{rw, rw, rw, rw, rw}
+	// combination 24/32
+	case i0 && !i1 && i2 && i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.Hijacker
+			io.ReaderFrom
+			http.Pusher
+		}{rw, rw, rw, rw, rw, rw}
+	// combination 25/32
+	case i0 && i1 && !i2 && !i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+		}{rw, rw, rw, rw}
+	// combination 26/32
+	case i0 && i1 && !i2 && !i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			http.Pusher
+		}{rw, rw, rw, rw, rw}
+	// combination 27/32
+	case i0 && i1 && !i2 && i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			io.ReaderFrom
+		}{rw, rw, rw, rw, rw}
+	// combination 28/32
+	case i0 && i1 && !i2 && i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			io.ReaderFrom
+			http.Pusher
+		}{rw, rw, rw, rw, rw, rw}
+	// combination 29/32
+	case i0 && i1 && i2 && !i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			http.Hijacker
+		}{rw, rw, rw, rw, rw}
+	// combination 30/32
+	case i0 && i1 && i2 && !i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			http.Hijacker
+			http.Pusher
+		}{rw, rw, rw, rw, rw, rw}
+	// combination 31/32
+	case i0 && i1 && i2 && i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			http.Hijacker
+			io.ReaderFrom
+		}{rw, rw, rw, rw, rw, rw}
+	// combination 32/32
+	case i0 && i1 && i2 && i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			http.Hijacker
+			io.ReaderFrom
+			http.Pusher
+		}{rw, rw, rw, rw, rw, rw, rw}
+	}
+	panic("unreachable")
+}
+
+type rw struct {
+	w http.ResponseWriter
+	h Hooks
+}
+
+func (w *rw) Unwrap() http.ResponseWriter {
+	return w.w
+}
+
+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)
+}
+
+type Unwrapper interface {
+	Unwrap() http.ResponseWriter
+}
+
+// Unwrap returns the underlying http.ResponseWriter from within zero or more
+// layers of httpsnoop wrappers.
+func Unwrap(w http.ResponseWriter) http.ResponseWriter {
+	if rw, ok := w.(Unwrapper); ok {
+		// recurse until rw.Unwrap() returns a non-Unwrapper
+		return Unwrap(rw.Unwrap())
+	} else {
+		return w
+	}
+}

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

@@ -0,0 +1,278 @@
+// +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 {
+			Unwrapper
+			http.ResponseWriter
+		}{rw, rw}
+	// combination 2/16
+	case !i0 && !i1 && !i2 && i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			io.ReaderFrom
+		}{rw, rw, rw}
+	// combination 3/16
+	case !i0 && !i1 && i2 && !i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Hijacker
+		}{rw, rw, rw}
+	// combination 4/16
+	case !i0 && !i1 && i2 && i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Hijacker
+			io.ReaderFrom
+		}{rw, rw, rw, rw}
+	// combination 5/16
+	case !i0 && i1 && !i2 && !i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.CloseNotifier
+		}{rw, rw, rw}
+	// combination 6/16
+	case !i0 && i1 && !i2 && i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.CloseNotifier
+			io.ReaderFrom
+		}{rw, rw, rw, rw}
+	// combination 7/16
+	case !i0 && i1 && i2 && !i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.CloseNotifier
+			http.Hijacker
+		}{rw, rw, rw, rw}
+	// combination 8/16
+	case !i0 && i1 && i2 && i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.CloseNotifier
+			http.Hijacker
+			io.ReaderFrom
+		}{rw, rw, rw, rw, rw}
+	// combination 9/16
+	case i0 && !i1 && !i2 && !i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+		}{rw, rw, rw}
+	// combination 10/16
+	case i0 && !i1 && !i2 && i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			io.ReaderFrom
+		}{rw, rw, rw, rw}
+	// combination 11/16
+	case i0 && !i1 && i2 && !i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.Hijacker
+		}{rw, rw, rw, rw}
+	// combination 12/16
+	case i0 && !i1 && i2 && i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.Hijacker
+			io.ReaderFrom
+		}{rw, rw, rw, rw, rw}
+	// combination 13/16
+	case i0 && i1 && !i2 && !i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+		}{rw, rw, rw, rw}
+	// combination 14/16
+	case i0 && i1 && !i2 && i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			io.ReaderFrom
+		}{rw, rw, rw, rw, rw}
+	// combination 15/16
+	case i0 && i1 && i2 && !i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			http.Hijacker
+		}{rw, rw, rw, rw, rw}
+	// combination 16/16
+	case i0 && i1 && i2 && i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			http.Hijacker
+			io.ReaderFrom
+		}{rw, rw, rw, rw, rw, rw}
+	}
+	panic("unreachable")
+}
+
+type rw struct {
+	w http.ResponseWriter
+	h Hooks
+}
+
+func (w *rw) Unwrap() http.ResponseWriter {
+	return w.w
+}
+
+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)
+}
+
+type Unwrapper interface {
+	Unwrap() http.ResponseWriter
+}
+
+// Unwrap returns the underlying http.ResponseWriter from within zero or more
+// layers of httpsnoop wrappers.
+func Unwrap(w http.ResponseWriter) http.ResponseWriter {
+	if rw, ok := w.(Unwrapper); ok {
+		// recurse until rw.Unwrap() returns a non-Unwrapper
+		return Unwrap(rw.Unwrap())
+	} else {
+		return w
+	}
+}

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://www.ietf.org/archive/id/draft-peabody-dispatch-new-uuid-format-04.html) 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 04](https://www.ietf.org/archive/id/draft-peabody-dispatch-new-uuid-format-04.html#)

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

@@ -0,0 +1,234 @@
+// 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 (
+	"errors"
+	"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
+}
+
+var errInvalidFormat = errors.New("uuid: invalid UUID format")
+
+func fromHexChar(c byte) byte {
+	switch {
+	case '0' <= c && c <= '9':
+		return c - '0'
+	case 'a' <= c && c <= 'f':
+		return c - 'a' + 10
+	case 'A' <= c && c <= 'F':
+		return c - 'A' + 10
+	}
+	return 255
+}
+
+// Parse parses the UUID stored in the string text. Parsing and supported
+// formats are the same as UnmarshalText.
+func (u *UUID) Parse(s string) error {
+	switch len(s) {
+	case 32: // hash
+	case 36: // canonical
+	case 34, 38:
+		if s[0] != '{' || s[len(s)-1] != '}' {
+			return fmt.Errorf("uuid: incorrect UUID format in string %q", s)
+		}
+		s = s[1 : len(s)-1]
+	case 41, 45:
+		if s[:9] != "urn:uuid:" {
+			return fmt.Errorf("uuid: incorrect UUID format in string %q", s[:9])
+		}
+		s = s[9:]
+	default:
+		return fmt.Errorf("uuid: incorrect UUID length %d in string %q", len(s), s)
+	}
+	// canonical
+	if len(s) == 36 {
+		if s[8] != '-' || s[13] != '-' || s[18] != '-' || s[23] != '-' {
+			return fmt.Errorf("uuid: incorrect UUID format in string %q", s)
+		}
+		for i, x := range [16]byte{
+			0, 2, 4, 6,
+			9, 11,
+			14, 16,
+			19, 21,
+			24, 26, 28, 30, 32, 34,
+		} {
+			v1 := fromHexChar(s[x])
+			v2 := fromHexChar(s[x+1])
+			if v1|v2 == 255 {
+				return errInvalidFormat
+			}
+			u[i] = (v1 << 4) | v2
+		}
+		return nil
+	}
+	// hash like
+	for i := 0; i < 32; i += 2 {
+		v1 := fromHexChar(s[i])
+		v2 := fromHexChar(s[i+1])
+		if v1|v2 == 255 {
+			return errInvalidFormat
+		}
+		u[i/2] = (v1 << 4) | v2
+	}
+	return nil
+}
+
+// FromString returns a UUID parsed from the input string.
+// Input is expected in a form accepted by UnmarshalText.
+func FromString(text string) (UUID, error) {
+	var u UUID
+	err := u.Parse(text)
+	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) {
+	var buf [36]byte
+	encodeCanonical(buf[:], u)
+	return buf[:], 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(b []byte) error {
+	switch len(b) {
+	case 32: // hash
+	case 36: // canonical
+	case 34, 38:
+		if b[0] != '{' || b[len(b)-1] != '}' {
+			return fmt.Errorf("uuid: incorrect UUID format in string %q", b)
+		}
+		b = b[1 : len(b)-1]
+	case 41, 45:
+		if string(b[:9]) != "urn:uuid:" {
+			return fmt.Errorf("uuid: incorrect UUID format in string %q", b[:9])
+		}
+		b = b[9:]
+	default:
+		return fmt.Errorf("uuid: incorrect UUID length %d in string %q", len(b), b)
+	}
+	if len(b) == 36 {
+		if b[8] != '-' || b[13] != '-' || b[18] != '-' || b[23] != '-' {
+			return fmt.Errorf("uuid: incorrect UUID format in string %q", b)
+		}
+		for i, x := range [16]byte{
+			0, 2, 4, 6,
+			9, 11,
+			14, 16,
+			19, 21,
+			24, 26, 28, 30, 32, 34,
+		} {
+			v1 := fromHexChar(b[x])
+			v2 := fromHexChar(b[x+1])
+			if v1|v2 == 255 {
+				return errInvalidFormat
+			}
+			u[i] = (v1 << 4) | v2
+		}
+		return nil
+	}
+	for i := 0; i < 32; i += 2 {
+		v1 := fromHexChar(b[i])
+		v2 := fromHexChar(b[i+1])
+		if v1|v2 == 255 {
+			return errInvalidFormat
+		}
+		u[i/2] = (v1 << 4) | v2
+	}
+	return nil
+}
+
+// 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 +1,48 @@
+// 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.
+
+//go:build gofuzz
+// +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 +1,456 @@
+// 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
+
+// EpochFunc is the function type used to provide the current time.
+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. It supports single-node batch generation (multiple UUIDs in the same timestamp) with a Monotonic Random counter.
+//
+// This is implemented based on revision 04 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
+}
+
+// GenOption is a function type that can be used to configure a Gen generator.
+type GenOption func(*Gen)
+
+// 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 NewGenWithOptions(WithHWAddrFunc(hwaf))
+}
+
+// NewGenWithOptions returns a new instance of Gen with the options provided.
+// Most people should use NewGen() or NewGenWithHWAF() instead.
+//
+// To customize the generator, you can pass in one or more GenOption functions.
+// For example:
+//
+//	gen := NewGenWithOptions(
+//	    WithHWAddrFunc(myHWAddrFunc),
+//	    WithEpochFunc(myEpochFunc),
+//	    WithRandomReader(myRandomReader),
+//	)
+//
+// NewGenWithOptions(WithHWAddrFunc(myHWAddrFunc)) is equivalent to calling
+// NewGenWithHWAF(myHWAddrFunc)
+// NewGenWithOptions() is equivalent to calling NewGen()
+func NewGenWithOptions(opts ...GenOption) *Gen {
+	gen := &Gen{
+		epochFunc:  time.Now,
+		hwAddrFunc: defaultHWAddrFunc,
+		rand:       rand.Reader,
+	}
+
+	for _, opt := range opts {
+		opt(gen)
+	}
+
+	return gen
+}
+
+// WithHWAddrFunc is a GenOption that allows you to provide your own HWAddrFunc
+// function.
+// When this option is nil, the defaultHWAddrFunc is used.
+func WithHWAddrFunc(hwaf HWAddrFunc) GenOption {
+	return func(gen *Gen) {
+		if hwaf == nil {
+			hwaf = defaultHWAddrFunc
+		}
+
+		gen.hwAddrFunc = hwaf
+	}
+}
+
+// WithEpochFunc is a GenOption that allows you to provide your own EpochFunc
+// function.
+// When this option is nil, time.Now is used.
+func WithEpochFunc(epochf EpochFunc) GenOption {
+	return func(gen *Gen) {
+		if epochf == nil {
+			epochf = time.Now
+		}
+
+		gen.epochFunc = epochf
+	}
+}
+
+// WithRandomReader is a GenOption that allows you to provide your own random
+// reader.
+// When this option is nil, the default rand.Reader is used.
+func WithRandomReader(reader io.Reader) GenOption {
+	return func(gen *Gen) {
+		if reader == nil {
+			reader = rand.Reader
+		}
+
+		gen.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(false)
+	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(false)
+	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,V6 and V7 UUIDs.
+//
+//	When useUnixTSMs is false, it uses the Coordinated Universal Time (UTC) as a count of 100-
+//
+// nanosecond intervals since 00:00:00.00, 15 October 1582 (the date of Gregorian reform to the Christian calendar).
+func (g *Gen) getClockSequence(useUnixTSMs bool) (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()
+
+	var timeNow uint64
+	if useUnixTSMs {
+		timeNow = uint64(g.epochFunc().UnixMilli())
+	} else {
+		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 04 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
+	/* https://www.ietf.org/archive/id/draft-peabody-dispatch-new-uuid-format-04.html#name-uuid-version-7
+		0                   1                   2                   3
+	    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+	   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+	   |                           unix_ts_ms                          |
+	   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+	   |          unix_ts_ms           |  ver  |       rand_a          |
+	   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+	   |var|                        rand_b                             |
+	   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+	   |                            rand_b                             |
+	   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ */
+
+	ms, clockSeq, err := g.getClockSequence(true)
+	if err != nil {
+		return Nil, err
+	}
+	//UUIDv7 features a 48 bit timestamp. First 32bit (4bytes) represents seconds since 1970, followed by 2 bytes for the ms granularity.
+	u[0] = byte(ms >> 40) //1-6 bytes: big-endian unsigned number of Unix epoch timestamp
+	u[1] = byte(ms >> 32)
+	u[2] = byte(ms >> 24)
+	u[3] = byte(ms >> 16)
+	u[4] = byte(ms >> 8)
+	u[5] = byte(ms)
+
+	//support batching by using a monotonic pseudo-random sequence
+	//The 6th byte contains the version and partially rand_a data.
+	//We will lose the most significant bites from the clockSeq (with SetVersion), but it is ok, we need the least significant that contains the counter to ensure the monotonic property
+	binary.BigEndian.PutUint16(u[6:8], clockSeq) // set rand_a with clock seq which is random and monotonic
+
+	//override first 4bits of u[6].
+	u.SetVersion(V7)
+
+	//set rand_b 64bits of pseudo-random bits (first 2 will be overridden)
+	if _, err = io.ReadFull(g.rand, u[8:16]); err != nil {
+		return Nil, err
+	}
+	//override first 2 bits of byte[8] for the variant
+	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 +1,116 @@
+// 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 (
+	"database/sql"
+	"database/sql/driver"
+	"fmt"
+)
+
+var _ driver.Valuer = UUID{}
+var _ sql.Scanner = (*UUID)(nil)
+
+// 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:
+		uu, err := FromString(src)
+		*u = uu
+		return err
+	}
+
+	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)
+}
+
+var nullJSON = []byte("null")
+
+// MarshalJSON marshals the NullUUID as null or the nested UUID
+func (u NullUUID) MarshalJSON() ([]byte, error) {
+	if !u.Valid {
+		return nullJSON, nil
+	}
+	var buf [38]byte
+	buf[0] = '"'
+	encodeCanonical(buf[1:37], u.UUID)
+	buf[37] = '"'
+	return buf[:], nil
+}
+
+// UnmarshalJSON unmarshals a NullUUID
+func (u *NullUUID) UnmarshalJSON(b []byte) error {
+	if string(b) == "null" {
+		u.UUID, u.Valid = Nil, false
+		return nil
+	}
+	if n := len(b); n >= 2 && b[0] == '"' {
+		b = b[1 : n-1]
+	}
+	err := u.UUID.UnmarshalText(b)
+	u.Valid = (err == nil)
+	return err
+}

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

@@ -0,0 +1,285 @@
+// 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"
+	"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
+}
+
+// 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[:]
+}
+
+// encodeCanonical encodes the canonical RFC-4122 form of UUID u into the
+// first 36 bytes dst.
+func encodeCanonical(dst []byte, u UUID) {
+	const hextable = "0123456789abcdef"
+	dst[8] = '-'
+	dst[13] = '-'
+	dst[18] = '-'
+	dst[23] = '-'
+	for i, x := range [16]byte{
+		0, 2, 4, 6,
+		9, 11,
+		14, 16,
+		19, 21,
+		24, 26, 28, 30, 32, 34,
+	} {
+		c := u[i]
+		dst[x] = hextable[c>>4]
+		dst[x+1] = hextable[c&0x0f]
+	}
+}
+
+// String returns a canonical RFC-4122 string representation of the UUID:
+// xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx.
+func (u UUID) String() string {
+	var buf [36]byte
+	encodeCanonical(buf[:], u)
+	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) {
+	if c == 'v' && f.Flag('#') {
+		fmt.Fprintf(f, "%#v", [Size]byte(u))
+		return
+	}
+	switch c {
+	case 'x', 'X':
+		b := make([]byte, 32)
+		hex.Encode(b, u[:])
+		if c == 'X' {
+			toUpperHex(b)
+		}
+		_, _ = f.Write(b)
+	case 'v', 's', 'S':
+		b, _ := u.MarshalText()
+		if c == 'S' {
+			toUpperHex(b)
+		}
+		_, _ = f.Write(b)
+	case 'q':
+		b := make([]byte, 38)
+		b[0] = '"'
+		encodeCanonical(b[1:], u)
+		b[37] = '"'
+		_, _ = f.Write(b)
+	default:
+		// invalid/unsupported format verb
+		fmt.Fprintf(f, "%%!%c(uuid.UUID=%s)", c, u.String())
+	}
+}
+
+func toUpperHex(b []byte) {
+	for i, c := range b {
+		if 'a' <= c && c <= 'f' {
+			b[i] = c - ('a' - 'A')
+		}
+	}
+}
+
+// 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/.editorconfig

@@ -0,0 +1,20 @@
+; https://editorconfig.org/
+
+root = true
+
+[*]
+insert_final_newline = true
+charset = utf-8
+trim_trailing_whitespace = true
+indent_style = space
+indent_size = 2
+
+[{Makefile,go.mod,go.sum,*.go,.gitmodules}]
+indent_style = tab
+indent_size = 4
+
+[*.md]
+indent_size = 4
+trim_trailing_whitespace = false
+
+eclint_indent_style = unset

vendor/github.com/gorilla/handlers/.gitignore

@@ -0,0 +1,2 @@
+# Output of the go test coverage tool
+coverage.coverprofile

vendor/github.com/gorilla/handlers/LICENSE

@@ -0,0 +1,27 @@
+Copyright (c) 2023 The Gorilla 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/gorilla/handlers/Makefile

@@ -0,0 +1,34 @@
+GO_LINT=$(shell which golangci-lint 2> /dev/null || echo '')
+GO_LINT_URI=github.com/golangci/golangci-lint/cmd/golangci-lint@latest
+
+GO_SEC=$(shell which gosec 2> /dev/null || echo '')
+GO_SEC_URI=github.com/securego/gosec/v2/cmd/gosec@latest
+
+GO_VULNCHECK=$(shell which govulncheck 2> /dev/null || echo '')
+GO_VULNCHECK_URI=golang.org/x/vuln/cmd/govulncheck@latest
+
+.PHONY: verify
+verify: sec govulncheck lint test
+
+.PHONY: lint
+lint:
+	$(if $(GO_LINT), ,go install $(GO_LINT_URI))
+	@echo "##### Running golangci-lint #####"
+	golangci-lint run -v
+
+.PHONY: sec
+sec:
+	$(if $(GO_SEC), ,go install $(GO_SEC_URI))
+	@echo "##### Running gosec #####"
+	gosec ./...
+
+.PHONY: govulncheck
+govulncheck:
+	$(if $(GO_VULNCHECK), ,go install $(GO_VULNCHECK_URI))
+	@echo "##### Running govulncheck #####"
+	govulncheck ./...
+
+.PHONY: test
+test:
+	@echo "##### Running tests #####"
+	go test -race -cover -coverprofile=coverage.coverprofile -covermode=atomic -v ./...

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

@@ -0,0 +1,56 @@
+# gorilla/handlers
+
+![Testing](https://github.com/gorilla/handlers/actions/workflows/test.yml/badge.svg)
+[![Codecov](https://codecov.io/github/gorilla/handlers/branch/main/graph/badge.svg)](https://codecov.io/github/gorilla/handlers)
+[![GoDoc](https://godoc.org/github.com/gorilla/handlers?status.svg)](https://godoc.org/github.com/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 +1,73 @@
+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 (cw *compressResponseWriter) Flush() {
+	// Flush compressed data if compressor supports it.
+	if f, ok := cw.compressor.(flusher); ok {
+		_ = f.Flush()
+	}
+	// Flush HTTP response.
+	if f, ok := cw.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 +1,352 @@
+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 = http.StatusOK
+	defaultCorsMethods          = []string{http.MethodGet, http.MethodHead, http.MethodPost}
+	defaultCorsHeaders          = []string{"Accept", "Accept-Language", "Content-Language", "Origin"}
+	// (WebKit/Safari v9 sends the Origin header by default in AJAX requests).
+)
+
+const (
+	corsOptionMethod           string = http.MethodOptions
+	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) //TODO: @bharat-rajani, return error to caller if not nil?
+	}
+
+	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 +1,150 @@
+// 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 == http.MethodOptions {
+			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 == http.MethodPut || r.Method == http.MethodPost || r.Method == http.MethodPatch) {
+			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 == http.MethodPost {
+			om := r.FormValue(HTTPMethodOverrideFormKey)
+			if om == "" {
+				om = r.Header.Get(HTTPMethodOverrideHeader)
+			}
+			if om == http.MethodPut || om == http.MethodPatch || om == http.MethodDelete {
+				r.Method = om
+			}
+		}
+		h.ServeHTTP(w, r)
+	})
+}

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

@@ -0,0 +1,246 @@
+// 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 {
+		err := req.MultipartForm.RemoveAll()
+		if err != nil {
+			return
+		}
+	}
+
+	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:] { //nolint: wastedassign //TODO: why width starts from 0and reassigned as 1
+		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
+
+	switch {
+	case r.Header.Get(xForwardedFor) != "":
+		fwd := r.Header.Get(xForwardedFor)
+		// 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]
+	case r.Header.Get(xRealIP) != "":
+		addr = r.Header.Get(xRealIP)
+	case r.Header.Get(forwarded) != "":
+		// 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(r.Header.Get(forwarded)); 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 +1,98 @@
+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) //nolint:errcheck //TODO:
+		// @bharat-rajani should return type-assertion error but would break the API?
+		r.logger = logger
+	}
+}
+
+// PrintRecoveryStack is a functional option to enable
+// or disable printing stack traces on panic.
+func PrintRecoveryStack(shouldPrint bool) RecoveryOption {
+	return func(h http.Handler) {
+		r := h.(*recoveryHandler) //nolint:errcheck //TODO:
+		// @bharat-rajani should return type-assertion error but would break the API?
+		r.printStack = shouldPrint
+	}
+}
+
+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 +1,603 @@
+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)
+  - [macOS](#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` compiler 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`. |
+| Enable Serialization with `libsqlite3` | sqlite_serialize | Serialization and deserialization of a SQLite database is available by default, unless the build tag `libsqlite3` is set.<br><br>To enable this functionality even if `libsqlite3` is set, add the build tag `sqlite_serialize`. |
+| 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 macOS
+The simplest way to cross compile from macOS is to use [xgo](https://github.com/karalabe/xgo).
+
+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
+```
+
+## macOS
+
+macOS 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 macOS, 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 macOS on x86:
+
+```bash
+go build -tags "darwin amd64"
+```
+
+To compile for macOS on ARM chips:
+
+```bash
+go build -tags "darwin arm64"
+```
+
+If you wish to link directly to libsqlite3, use the `libsqlite3` build tag:
+
+```
+# x86 
+go build -tags "libsqlite3 darwin amd64"
+# ARM
+go build -tags "libsqlite3 darwin arm64"
+```
+
+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 any
+}
+
+var handleLock sync.Mutex
+var handleVals = make(map[unsafe.Pointer]handleVal)
+
+func newHandle(db *SQLiteConn, v any) 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) any {
+	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 any")
+		}
+		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 any) 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 *any:
+			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 *any:
+			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 *any:
+		*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 any) 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 +1,134 @@
+/*
+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 any) 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 any) []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 any) []byte {
+	return func(pass []byte, hash any) []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 any) []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 any) []byte {
+	return func(pass []byte, hash any) []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 any) []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 any) []byte {
+	return func(pass []byte, hash any) []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 any) []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 any) []byte {
+	return func(pass []byte, hash any) []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 +1,54 @@
+// 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.
+
+//go:build cgo && go1.8
+// +build cgo,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) {
+	return c.query(ctx, query, args)
+}
+
+// ExecContext implement ExecerContext.
+func (c *SQLiteConn) ExecContext(ctx context.Context, query string, args []driver.NamedValue) (driver.Result, error) {
+	return c.exec(ctx, query, args)
+}
+
+// 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) {
+	return s.query(ctx, args)
+}
+
+// ExecContext implement ExecerContext.
+func (s *SQLiteStmt) ExecContext(ctx context.Context, args []driver.NamedValue) (driver.Result, error) {
+	return s.exec(ctx, args)
+}

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

@@ -0,0 +1,23 @@
+// 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.
+
+//go:build libsqlite3
+// +build libsqlite3
+
+package sqlite3
+
+/*
+#cgo CFLAGS: -DUSE_LIBSQLITE3
+#cgo linux LDFLAGS: -lsqlite3
+#cgo darwin,amd64 LDFLAGS: -L/usr/local/opt/sqlite/lib -lsqlite3
+#cgo darwin,amd64 CFLAGS:  -I/usr/local/opt/sqlite/include
+#cgo darwin,arm64 LDFLAGS: -L/opt/homebrew/opt/sqlite/lib -lsqlite3
+#cgo darwin,arm64 CFLAGS:  -I/opt/homebrew/opt/sqlite/include
+#cgo openbsd LDFLAGS: -lsqlite3
+#cgo solaris LDFLAGS: -lsqlite3
+#cgo windows LDFLAGS: -lsqlite3
+#cgo zos LDFLAGS: -lsqlite3
+*/
+import "C"

vendor/github.com/mattn/go-sqlite3/sqlite3_load_extension.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.
+
+//go:build !sqlite_omit_load_extension
+// +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 +1,25 @@
+// 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.
+
+//go:build sqlite_omit_load_extension
+// +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 +1,16 @@
+// 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.
+
+//go:build sqlite_allow_uri_authority
+// +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.
+
+//go:build !windows && sqlite_app_armor
+// +build !windows,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 +1,22 @@
+//go:build sqlite_column_metadata
+// +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 +1,16 @@
+// 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.
+
+//go:build sqlite_foreign_keys
+// +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 +1,15 @@
+// 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.
+
+//go:build sqlite_fts5 || fts5
+// +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 +1,20 @@
+// 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.
+
+//go:build sqlite_icu || icu
+// +build sqlite_icu icu
+
+package sqlite3
+
+/*
+#cgo LDFLAGS: -licuuc -licui18n
+#cgo CFLAGS: -DSQLITE_ENABLE_ICU
+#cgo darwin,amd64 CFLAGS:  -I/usr/local/opt/icu4c/include
+#cgo darwin,amd64 LDFLAGS: -L/usr/local/opt/icu4c/lib
+#cgo darwin,arm64 CFLAGS:  -I/opt/homebrew/opt/icu4c/include
+#cgo darwin,arm64 LDFLAGS: -L/opt/homebrew/opt/icu4c/lib
+#cgo openbsd LDFLAGS: -lsqlite3
+*/
+import "C"

vendor/github.com/mattn/go-sqlite3/sqlite3_opt_introspect.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.
+
+//go:build sqlite_introspect
+// +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 +1,15 @@
+// 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_math_functions
+// +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 +1,21 @@
+// 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.
+
+//go:build cgo
+// +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 +1,113 @@
+// 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.
+
+//go:build sqlite_preupdate_hook
+// +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 []any, new bool) error {
+	for i := 0; i < d.Count() && i < len(dest); i++ {
+		var val *C.sqlite3_value
+		var src any
+
+		// 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 ...any) 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 ...any) 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 +1,22 @@
+// 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.
+
+//go:build !sqlite_preupdate_hook && cgo
+// +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
+}