A simple reverse-proxy in Go that enables CORS

proxy.go

package main

import (
	"log"
	"net/http"
	"net/http/httputil"
	"net/url"
)

func main() {
	http.HandleFunc("/", handler)

	log.Print("listening :8080")
	log.Fatal(http.ListenAndServe(":8080", nil))
}

var u, _ = url.Parse("https://jobs.github.com/")

func handler(w http.ResponseWriter, r *http.Request) {
	w.Header().Set("Access-Control-Allow-Origin", "*")
	w.Header().Set("Access-Control-Allow-Methods", "POST, GET, OPTIONS, PUT, DELETE")
	w.Header().Set("Access-Control-Allow-Headers", "Accept, Content-Type, Content-Length, Accept-Encoding, X-CSRF-Token, Authorization")
	
	proxy := httputil.NewSingleHostReverseProxy(u)

	r.URL.Host = u.Host
	r.URL.Scheme = u.Scheme
	r.Header.Set("X-Forwarded-Host", r.Header.Get("Host"))
	r.Host = u.Host

	w.Header().Set("Access-Control-Allow-Origin", "*")
	proxy.ServeHTTP(w, r)
}