aleph1.co.uk Git - yaffs-website/blob - web/core/lib/Drupal/Core/EventSubscriber/RouteAccessResponseSubscriber.php

   1 <?php
   2
   3 namespace Drupal\Core\EventSubscriber;
   4
   5 use Drupal\Core\Cache\CacheableResponseInterface;
   6 use Drupal\Core\Routing\AccessAwareRouterInterface;
   7 use Symfony\Component\HttpKernel\Event\FilterResponseEvent;
   8 use Symfony\Component\HttpKernel\KernelEvents;
   9 use Symfony\Component\EventDispatcher\EventSubscriberInterface;
  10
  11 /**
  12  * Response subscriber to bubble the route's access result's cacheability.
  13  *
  14  * During routing, access checking is performed. The corresponding access result
  15  * is stored in the Request object's attributes, just like the matching route
  16  * object is. In case of a cacheable response, the route's access result also
  17  * determined the content of the response, and therefore the cacheability of the
  18  * route's access result should also be applied to the resulting response.
  19  *
  20  * @see \Drupal\Core\Routing\AccessAwareRouterInterface::ACCESS_RESULT
  21  * @see \Drupal\Core\Routing\AccessAwareRouter::matchRequest()
  22  * @see \Drupal\Core\Routing\AccessAwareRouter::checkAccess()
  23  */
  24 class RouteAccessResponseSubscriber implements EventSubscriberInterface {
  25
  26   /**
  27    * Bubbles the route's access result' cacheability metadata.
  28    *
  29    * @param \Symfony\Component\HttpKernel\Event\FilterResponseEvent $event
  30    *   The event to process.
  31    */
  32   public function onRespond(FilterResponseEvent $event) {
  33     if (!$event->isMasterRequest()) {
  34       return;
  35     }
  36
  37     $response = $event->getResponse();
  38     if (!$response instanceof CacheableResponseInterface) {
  39       return;
  40     }
  41
  42     $request = $event->getRequest();
  43     $access_result = $request->attributes->get(AccessAwareRouterInterface::ACCESS_RESULT);
  44     $response->addCacheableDependency($access_result);
  45   }
  46
  47   /**
  48    * {@inheritdoc}
  49    */
  50   public static function getSubscribedEvents() {
  51     // Priority 10, so that it runs before FinishResponseSubscriber, which will
  52     // expose the cacheability metadata in the form of headers.
  53     $events[KernelEvents::RESPONSE][] = ['onRespond', 10];
  54     return $events;
  55   }
  56
  57 }