Simple reverse proxy in Go

revprox.go

package main

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

func main() {
        remote, err := url.Parse("http://google.com")
        if err != nil {
                panic(err)
        }

        handler := func(p *httputil.ReverseProxy) func(http.ResponseWriter, *http.Request) {
                return func(w http.ResponseWriter, r *http.Request) {
                        log.Println(r.URL)
                        r.Host = remote.Host
                        w.Header().Set("X-Ben", "Rad")
                        p.ServeHTTP(w, r)
                }
        }
        
        proxy := httputil.NewSingleHostReverseProxy(remote)
        http.HandleFunc("/", handler(proxy))
        err = http.ListenAndServe(":8080", nil)
        if err != nil {
                panic(err)
        }
}

Added "r.Host = remote.Host" to fix 404 issues

undeclared name: remote

function handler should be placed in function main:

	handler := func(p *httputil.ReverseProxy) func(http.ResponseWriter, *http.Request) {
		return func(w http.ResponseWriter, r *http.Request) {
			log.Println(r.URL)
			r.Host = remote.Host
			w.Header().Set("X-Ben", "Rad")
			p.ServeHTTP(w, r)
		}
	}

Thanks @lwzm!

Great!

hi, after saved this file, how can i try？

go run main.go
then
curl localhost:8080
I think

Made some changes to add support for ssl. And cleanup handler.

`package main

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

func main() {
// Replace 'target' with the URL of the server you want to proxy to
target, err := url.Parse("https://example.com")
if err != nil {
panic(err)
}

// Create a new ReverseProxy instance
proxy := httputil.NewSingleHostReverseProxy(target)
// Configure the reverse proxy to use HTTPS
proxy.Transport = &http.Transport{
    TLSClientConfig: &tls.Config{InsecureSkipVerify: true},
}
// Create a handler function that logs the URL and forwards the request to the proxy
handler := func(w http.ResponseWriter, r *http.Request) {
    log.Println(r.URL)
    r.Host = target.Host
	//w.Header().Set("X-Ben", "radi")
    proxy.ServeHTTP(w, r)
}

// Register the handler function with the HTTP server
http.HandleFunc("/", handler)

// Start the HTTP server
err = http.ListenAndServe(":3000", nil)
if err != nil {
    panic(err)
}

}`

Modified it to use struct and ssl
https://gist.github.com/c0d3kid/862276a6291e4aeaf2638e5f7e93a954

Helpful, ta, used this to transparently adjust some query parameters for certain requests.