GitHub - sebest/xff: A Golang Middleware to handle X-Forwarded-For Header

Package xff is a net/http middleware/handler to parse Forwarded HTTP Extension in Golang.

Example usage

Install xff:

go get github.com/sebest/xff

Edit server.go:

package main

import (
  "net/http"

  "github.com/sebest/xff"
)

func main() {
  handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
    w.Write([]byte("hello from " + r.RemoteAddr + "\n"))
  })

  xffmw, _ := xff.Default()
  http.ListenAndServe(":8080", xffmw.Handler(handler))
}

Then run your server:

The server now runs on localhost:8080:

$ curl -D - -H 'X-Forwarded-For: 42.42.42.42' http://localhost:8080/
HTTP/1.1 200 OK
Date: Fri, 20 Feb 2015 20:03:02 GMT
Content-Length: 29
Content-Type: text/plain; charset=utf-8

hello from 42.42.42.42:52661