code: protected static function ip()
  	{
  		$request = System::getContainer()->get('request_stack')->getCurrentRequest();
  
  		if ($request === null)
  		{
  			return '';
  		}
  
  		return $request->getClientIp();
  	}
docs: Return the real REMOTE_ADDR even if a proxy server is used
  
  @return string The IP address of the client