“Symfony 3.4 Control de caché” Código de respuesta

Symfony 3.4 Control de caché

<?php

namespace AppBundle\Listener;

use Symfony\Component\HttpKernel\Event\FilterResponseEvent;

class ResponseListener
{
    public function onKernelResponse(FilterResponseEvent $event)
    {
        $response = $event->getResponse();

        $controller = $event->getRequest()->attributes->get('_controller');
        $requiredAssetAction = "AppBundle\Controller\Website\AssetsController::assetAction";

        if ($controller == $requiredAssetAction) {
            $response->headers->addCacheControlDirective('max-age', 900);
            $response->headers->addCacheControlDirective('s-maxage', 900);
            $response->headers->addCacheControlDirective('must-revalidate', true);
            $response->headers->addCacheControlDirective('public', true);
            $response->headers->removeCacheControlDirective('private');

        }

        $event->setResponse($response);
    }

}