Run Go binary server on PHP/Apache shared hosting

.htaccess

RewriteEngine on
RewriteCond %{REQUEST_URI} !^/up.php
# TODO: Handle random port.
# TODO: Use ProxyPass or ProxyPassMatch instead of mod_proxy's RewriteRule for better performance.
RewriteRule ^(.*) http://127.0.0.1:8080/$1 [P]

main.go

package main

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

func main() {
	http.HandleFunc("/", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.Write([]byte(r.RemoteAddr + " - " + r.URL.Path))
	}))

	listener, err := net.Listen("tcp", ":0")
	if err != nil {
		panic(err)
	}

	port := listener.Addr().(*net.TCPAddr).Port

	// TODO: Save port and PID for .htaccess and up.php.
	//       If port information not accessible from .htaccess, generate a new .htaccess here.
	
	// TODO: Remove port information at exit.

	fmt.Printf("Running on :%d", port)
	panic(http.Serve(listener, nil))
}

up.php

<?php

// TODO: Check for Go server PID.
//       If PID information not available, jump to rerunning server.

// TODO: Handle random port.
$url = 'http://localhost:8080';

$ch = curl_init($url);
curl_setopt($ch, CURLOPT_HEADER, true);
curl_setopt($ch, CURLOPT_NOBODY, true);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_TIMEOUT, 30);
curl_exec($ch);
$code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
curl_close($ch);

if ($code >= 200 && $code < 400) exit();

// TODO: Kill current process and remove port information.
// TODO: Rerun server in background and redirect output to /dev/null.