package main

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

func fetchHandler(w http.ResponseWriter, r *http.Request) {
	path := r.URL.Path

	path = fmt.Sprintf("https://secure.gravatar.com%s", path)

	fmt.Println("need reverse url: ", path)

	rpURL, _ := url.Parse(path)

	proxy := httputil.NewSingleHostReverseProxy(rpURL)
	director := proxy.Director
	proxy.Director = func(r *http.Request) {
		director(r)
		r.Host = "secure.gravatar.com"
	}
	proxy.ServeHTTP(w, r)
}

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

	err := http.ListenAndServe(fmt.Sprintf(":%d", 80), nil)
	if err != nil {
		fmt.Println("run server error: ", err)
		return
	}
}