Simple PHP Proxy

This proxy script allows you to forward all HTTP/HTTPS requests to another server. Works for all common request types including GET, POST requests with files, PATCH and PUT requests. It has minimal set of requirements (PHP >=5.6, libcurl, gzip) which are available even on the smallest free hostings and has its own simple authorization and cookie support.

How to use

• Copy the Proxy.php script to publicly-accessible folder of a PHP web server (the script is standalone and has no PHP dependencies)
• Make a cURL request targeting this script
• Add Proxy-Auth header with auth key found here
• Add Proxy-Target-URL header with URL to be requested by the proxy
• (Optional) Add Proxy-Debug header for debug mode

In order to protect using proxy by unauthorized users, consider changing Proxy-Auth token in proxy source file and in all your requests.

How to use (via composer)

This might be useful when you want to redirect requests coming into your app.

• Run composer require zounar/php-proxy
• Add Proxy::run(); line to where you want to execute it (usually into a controller action)
  • In this example, the script is in AppController - actionProxy:

    use Zounar\PHPProxy\Proxy;
    
    class AppController extends Controller {
    
        public function actionProxy() {
            Proxy::$AUTH_KEY = '<your-new-key>';
            // Do your custom logic before running proxy
            $responseCode = Proxy::run();
            // Do your custom logic after running proxy
            // You can utilize HTTP response code returned from the run() method
        }
    }
    

• Make a cURL request to your web
  • In the example, it would be http://your-web.com/app/proxy
• Add Proxy-Auth header with auth key found here
• Add Proxy-Target-URL header with URL to be requested by the proxy
• (Optional) Add Proxy-Debug header for debug mode

In order to protect using proxy by unauthorized users, consider changing Proxy-Auth token by calling Proxy::$AUTH_KEY = '<your-new-key>'; before Proxy::run(). Then change the token in all your requests.

Usage example

Following example shows how to execute GET request to https://www.github.com. Proxy script is at http://www.foo.bar/Proxy.php. All proxy settings are kept default, the response is automatically echoed.

$request = curl_init('http://www.foo.bar/Proxy.php');

curl_setopt($request, CURLOPT_HTTPHEADER, array(
    'Proxy-Auth: Bj5pnZEX6DkcG6Nz6AjDUT1bvcGRVhRaXDuKDX9CjsEs2',
    'Proxy-Target-URL: https://www.github.com'
));

curl_exec($request);

Debugging

In order to show some debug info from the proxy, add Proxy-Debug: 1 header into the request. This will show debug info in plain-text containing request headers, response headers and response body.

$request = curl_init('http://www.foo.bar/Proxy.php');

curl_setopt($request, CURLOPT_HTTPHEADER, array(
    'Proxy-Auth: Bj5pnZEX6DkcG6Nz6AjDUT1bvcGRVhRaXDuKDX9CjsEs2',
    'Proxy-Target-URL: https://www.github.com',
    'Proxy-Debug: 1'
));

curl_exec($request);

Specifying User-Agent

Some sites may return different content for different user agents. In such case add User-Agent header to cURL request, it will be automatically passed to the request for target site. In this case it's Firefox 70 for Ubuntu.

$request = curl_init('http://www.foo.bar/Proxy.php');

curl_setopt($request, CURLOPT_HTTPHEADER, array(
    'User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:70.0) Gecko/20100101 Firefox/70.0',
    'Proxy-Auth: Bj5pnZEX6DkcG6Nz6AjDUT1bvcGRVhRaXDuKDX9CjsEs2',
    'Proxy-Target-URL: https://www.github.com'
));

curl_exec($request);

Error 301 Moved permanently

It might occur that there's a redirection when calling the proxy (not the target site), eg. during http -> https redirection. You can either modify/fix the proxy URL (which is recommended), or add CURLOPT_FOLLOWLOCATION option before curl_exec.

$request = curl_init('http://www.foo.bar/Proxy.php');

curl_setopt($request, CURLOPT_FOLLOWLOCATION, true );
curl_setopt($request, CURLOPT_HTTPHEADER, array(
    'Proxy-Auth: Bj5pnZEX6DkcG6Nz6AjDUT1bvcGRVhRaXDuKDX9CjsEs2',
    'Proxy-Target-URL: https://www.github.com'
));

curl_exec($request);

Save response into variable

The default cURL behavior is to echo the response of curl_exec. In order to save response into variable, all you have to do is to add CURLOPT_RETURNTRANSFER cURL option.

$request = curl_init('http://www.foo.bar/Proxy.php');

curl_setopt($request, CURLOPT_RETURNTRANSFER, true);
curl_setopt($request, CURLOPT_HTTPHEADER, array(
    'Proxy-Auth: Bj5pnZEX6DkcG6Nz6AjDUT1bvcGRVhRaXDuKDX9CjsEs2',
    'Proxy-Target-URL: https://www.github.com'
));

$response = curl_exec($request);