aleph1.co.uk Git - yaffs-website/blob - web/core/lib/Drupal/Core/EventSubscriber/Fast404ExceptionHtmlSubscriber.php

   1 <?php
   2
   3 namespace Drupal\Core\EventSubscriber;
   4
   5 use Drupal\Core\Config\ConfigFactoryInterface;
   6 use Drupal\Component\Utility\Html;
   7 use Symfony\Component\HttpFoundation\Response;
   8 use Symfony\Component\HttpKernel\Event\GetResponseForExceptionEvent;
   9 use Symfony\Component\HttpKernel\HttpKernelInterface;
  10
  11 /**
  12  * High-performance 404 exception subscriber.
  13  *
  14  * This subscriber will return a minimalist 404 response for HTML requests
  15  * without running a full page theming operation.
  16  */
  17 class Fast404ExceptionHtmlSubscriber extends HttpExceptionSubscriberBase {
  18
  19   /**
  20    * The HTTP kernel.
  21    *
  22    * @var \Symfony\Component\HttpKernel\HttpKernelInterface
  23    */
  24   protected $httpKernel;
  25
  26   /**
  27    * The config factory.
  28    *
  29    * @var \Drupal\Core\Config\ConfigFactoryInterface
  30    */
  31   protected $configFactory;
  32
  33   /**
  34    * Constructs a new Fast404ExceptionHtmlSubscriber.
  35    *
  36    * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
  37    *   The configuration factory.
  38    * @param \Symfony\Component\HttpKernel\HttpKernelInterface $http_kernel
  39    *   The HTTP Kernel service.
  40    */
  41   public function __construct(ConfigFactoryInterface $config_factory, HttpKernelInterface $http_kernel) {
  42     $this->configFactory = $config_factory;
  43     $this->httpKernel = $http_kernel;
  44   }
  45
  46   /**
  47    * {@inheritdoc}
  48    */
  49   protected static function getPriority() {
  50     // A very high priority so that it can take precedent over anything else,
  51     // and thus be fast.
  52     return 200;
  53   }
  54
  55   /**
  56    * {@inheritdoc}
  57    */
  58   protected function getHandledFormats() {
  59     return ['html'];
  60   }
  61
  62   /**
  63    * Handles a 404 error for HTML.
  64    *
  65    * @param \Symfony\Component\HttpKernel\Event\GetResponseForExceptionEvent $event
  66    *   The event to process.
  67    */
  68   public function on404(GetResponseForExceptionEvent $event) {
  69     $request = $event->getRequest();
  70
  71     $config = $this->configFactory->get('system.performance');
  72     $exclude_paths = $config->get('fast_404.exclude_paths');
  73     if ($config->get('fast_404.enabled') && $exclude_paths && !preg_match($exclude_paths, $request->getPathInfo())) {
  74       $fast_paths = $config->get('fast_404.paths');
  75       if ($fast_paths && preg_match($fast_paths, $request->getPathInfo())) {
  76         $fast_404_html = strtr($config->get('fast_404.html'), ['@path' => Html::escape($request->getUri())]);
  77         $response = new Response($fast_404_html, Response::HTTP_NOT_FOUND);
  78         $event->setResponse($response);
  79       }
  80     }
  81   }
  82
  83 }