vendor/sensio/framework-extra-bundle/src/EventListener/HttpCacheListener.php line 42

  1. <?php
  3. /*
  4.  * This file is part of the Symfony package.
  5.  *
  6.  * (c) Fabien Potencier <fabien@symfony.com>
  7.  *
  8.  * For the full copyright and license information, please view the LICENSE
  9.  * file that was distributed with this source code.
  10.  */
  12. namespace Sensio\Bundle\FrameworkExtraBundle\EventListener;
  14. use Sensio\Bundle\FrameworkExtraBundle\Configuration\Cache;
  15. use Symfony\Component\EventDispatcher\EventSubscriberInterface;
  16. use Symfony\Component\ExpressionLanguage\ExpressionLanguage;
  17. use Symfony\Component\HttpFoundation\Response;
  18. use Symfony\Component\HttpKernel\Event\KernelEvent;
  19. use Symfony\Component\HttpKernel\KernelEvents;
  21. /**
  22.  * HttpCacheListener handles HTTP cache headers.
  23.  *
  24.  * It can be configured via the Cache annotation.
  25.  *
  26.  * @author Fabien Potencier <fabien@symfony.com>
  27.  */
  28. class HttpCacheListener implements EventSubscriberInterface
  29. {
  30.     private $lastModifiedDates;
  31.     private $etags;
  32.     private $expressionLanguage;
  34.     public function __construct()
  35.     {
  36.         $this->lastModifiedDates = new \SplObjectStorage();
  37.         $this->etags = new \SplObjectStorage();
  38.     }
  40.     /**
  41.      * Handles HTTP validation headers.
  42.      */
  43.     public function onKernelController(KernelEvent $event)
  44.     {
  45.         $request = $event->getRequest();
  46.         $configuration = $request->attributes->get('_cache');
  47.         if (!$configuration instanceof Cache) {
  48.             return;
  49.         }
  51.         $response = new Response();
  53.         $lastModifiedDate = '';
  54.         if ($configuration->getLastModified()) {
  55.             $lastModifiedDate = $this->getExpressionLanguage()->evaluate($configuration->getLastModified(), $request->attributes->all());
  56.             $response->setLastModified($lastModifiedDate);
  57.         }
  59.         $etag = '';
  60.         if ($configuration->getEtag()) {
  61.             $etag = hash('sha256', $this->getExpressionLanguage()->evaluate($configuration->getEtag(), $request->attributes->all()));
  62.             $response->setEtag($etag);
  63.         }
  65.         if ($response->isNotModified($request)) {
  66.             $event->setController(function () use ($response) {
  67.                 return $response;
  68.             });
  69.             $event->stopPropagation();
  70.         } else {
  71.             if ($etag) {
  72.                 $this->etags[$request] = $etag;
  73.             }
  74.             if ($lastModifiedDate) {
  75.                 $this->lastModifiedDates[$request] = $lastModifiedDate;
  76.             }
  77.         }
  78.     }
  80.     /**
  81.      * Modifies the response to apply HTTP cache headers when needed.
  82.      */
  83.     public function onKernelResponse(KernelEvent $event)
  84.     {
  85.         $request = $event->getRequest();
  86.         $configuration = $request->attributes->get('_cache');
  88.         if (!$configuration instanceof Cache) {
  89.             return;
  90.         }
  92.         $response = $event->getResponse();
  94.         // http://tools.ietf.org/html/draft-ietf-httpbis-p4-conditional-12#section-3.1
  95.         if (!\in_array($response->getStatusCode(), [200, 203, 300, 301, 302, 304, 404, 410])) {
  96.             return;
  97.         }
  99.         if (!$response->headers->hasCacheControlDirective('s-maxage') && null !== $age = $configuration->getSMaxAge()) {
  100.             $age = $this->convertToSecondsIfNeeded($age);
  102.             $response->setSharedMaxAge($age);
  103.         }
  105.         if ($configuration->mustRevalidate()) {
  106.             $response->headers->addCacheControlDirective('must-revalidate');
  107.         }
  109.         if (!$response->headers->hasCacheControlDirective('max-age') && null !== $age = $configuration->getMaxAge()) {
  110.             $age = $this->convertToSecondsIfNeeded($age);
  112.             $response->setMaxAge($age);
  113.         }
  115.         if (!$response->headers->hasCacheControlDirective('max-stale') && null !== $stale = $configuration->getMaxStale()) {
  116.             $stale = $this->convertToSecondsIfNeeded($stale);
  118.             $response->headers->addCacheControlDirective('max-stale', $stale);
  119.         }
  121.         if (!$response->headers->hasCacheControlDirective('stale-while-revalidate') && null !== $staleWhileRevalidate = $configuration->getStaleWhileRevalidate()) {
  122.             $staleWhileRevalidate = $this->convertToSecondsIfNeeded($staleWhileRevalidate);
  124.             $response->headers->addCacheControlDirective('stale-while-revalidate', $staleWhileRevalidate);
  125.         }
  127.         if (!$response->headers->hasCacheControlDirective('stale-if-error') && null !== $staleIfError = $configuration->getStaleIfError()) {
  128.             $staleIfError = $this->convertToSecondsIfNeeded($staleIfError);
  130.             $response->headers->addCacheControlDirective('stale-if-error', $staleIfError);
  131.         }
  133.         if (!$response->headers->has('Expires') && null !== $configuration->getExpires()) {
  134.             $date = \DateTime::createFromFormat('U', strtotime($configuration->getExpires()), new \DateTimeZone('UTC'));
  135.             $response->setExpires($date);
  136.         }
  138.         if (!$response->headers->has('Vary') && null !== $configuration->getVary()) {
  139.             $response->setVary($configuration->getVary());
  140.         }
  142.         if ($configuration->isPublic()) {
  143.             $response->setPublic();
  144.         }
  146.         if ($configuration->isPrivate()) {
  147.             $response->setPrivate();
  148.         }
  150.         if (!$response->headers->has('Last-Modified') && isset($this->lastModifiedDates[$request])) {
  151.             $response->setLastModified($this->lastModifiedDates[$request]);
  153.             unset($this->lastModifiedDates[$request]);
  154.         }
  156.         if (!$response->headers->has('Etag') && isset($this->etags[$request])) {
  157.             $response->setEtag($this->etags[$request]);
  159.             unset($this->etags[$request]);
  160.         }
  161.     }
  163.     /**
  164.      * @return array
  165.      */
  166.     public static function getSubscribedEvents()
  167.     {
  168.         return [
  169.             KernelEvents::CONTROLLER => 'onKernelController',
  170.             KernelEvents::RESPONSE => 'onKernelResponse',
  171.         ];
  172.     }
  174.     private function getExpressionLanguage()
  175.     {
  176.         if (null === $this->expressionLanguage) {
  177.             if (!class_exists(ExpressionLanguage::class)) {
  178.                 throw new \RuntimeException('Unable to use expressions as the Symfony ExpressionLanguage component is not installed.');
  179.             }
  180.             $this->expressionLanguage = new ExpressionLanguage();
  181.         }
  183.         return $this->expressionLanguage;
  184.     }
  186.     /**
  187.      * @param int|string $time Time that can be either expressed in seconds or with relative time format (1 day, 2 weeks, ...)
  188.      *
  189.      * @return int
  190.      */
  191.     private function convertToSecondsIfNeeded($time)
  192.     {
  193.         if (!is_numeric($time)) {
  194.             $now = microtime(true);
  196.             $time = ceil(strtotime($time, (int) $now) - $now);
  197.         }
  199.         return $time;
  200.     }
  201. }