Super simple Go reverse proxy

proxy.go

package main

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

func main() {
	// Define the outgoing URL where requests will be forwarded
	outgoingURL, err := url.Parse("http://example.com") // Replace with your desired outgoing URL
	if err != nil {
		panic(err)
	}

	// Create a reverse proxy that forwards requests to the outgoing URL
	proxy := httputil.NewSingleHostReverseProxy(outgoingURL)

	// Handler function to handle incoming requests
	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("Access-Control-Allow-Origin", "*")
		w.Header().Set("Access-Control-Allow-Methods", "GET, POST, PUT, DELETE, OPTIONS")
		w.Header().Set("Access-Control-Allow-Headers", "Content-Type, Authorization")
		// Modify the request Host header to match the outgoing URL
		r.Host = outgoingURL.Host

		// Serve the request using the reverse proxy
		proxy.ServeHTTP(w, r)
	})

	// Start the server on 127.0.0.1:8080
	addr := "127.0.0.1:8080"
	fmt.Printf("Proxy server is running on http://%s\n", addr)
	if err := http.ListenAndServe(addr, nil); err != nil {
		panic(err)
	}
}