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EDGEPROXY.md

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+# edge proxy
+edge proxy is an optional feature that allows routing some extractor requests through a custom proxy endpoint, instead of a classic http/https proxy. this is useful if you want to centralize or control the traffic of certain platforms via your own proxy service, for example to bypass geo-restrictions, add caching, logging, or other customizations.
+
+## configuration
+edge proxy is configured via the `ext-cfg.yaml` file.  
+you can set the proxy url for each extractor that supports it.  
+example:
+
+```yaml
+instagram_share:
+  edge_proxy_url: https://example.com
+
+reddit:
+  https_proxy: https://example.com
+```
+
+## response format
+the edge proxy must respond with a JSON object in the following format (see [models.EdgeProxyResponse](models/edgeproxy.go))
+
+```json
+{
+  "url": "https://example.com/resource",
+  "status_code": 200,
+  "text": "response body",
+  "headers": {
+    "Content-Type": "application/json"
+  },
+  "cookies": [
+    "cookie1=value1; Path=/; HttpOnly",
+    "cookie2=value2; Path=/"
+  ]
+}
+```
+
+## http proxy vs edge proxy
+the main difference between http proxy and edge proxy is that http proxy is a standard proxy that forwards requests and responses, while edge proxy is a custom proxy that can modify the requests and responses in any way you want.
+
+## notes
+* edge proxy is for advanced use ant not required for most users.
+* this feature is experimental and may change in the future.
+* you can check full implementation of the edge proxy in the [edgeproxy](util/edgeproxy.go) package.