class Fast404ExceptionHtmlSubscriber in Drupal 8

High-performance 404 exception subscriber.

This subscriber will return a minimalist 404 response for HTML requests without running a full page theming operation.

Hierarchy

• class \Drupal\Core\EventSubscriber\HttpExceptionSubscriberBase implements \Symfony\Component\EventDispatcher\EventSubscriberInterface
  • class \Drupal\Core\EventSubscriber\Fast404ExceptionHtmlSubscriber

1 string reference to 'Fast404ExceptionHtmlSubscriber'

core.services.yml in core/core.services.yml

core/core.services.yml

1 service uses Fast404ExceptionHtmlSubscriber

exception.fast_404_html in core/core.services.yml

Drupal\Core\EventSubscriber\Fast404ExceptionHtmlSubscriber

File

core/lib/Drupal/Core/EventSubscriber/Fast404ExceptionHtmlSubscriber.php, line 17

Namespace

Drupal\Core\EventSubscriber

class Fast404ExceptionHtmlSubscriber extends HttpExceptionSubscriberBase {

  /**
   * The HTTP kernel.
   *
   * @var \Symfony\Component\HttpKernel\HttpKernelInterface
   */
  protected $httpKernel;

  /**
   * The config factory.
   *
   * @var \Drupal\Core\Config\ConfigFactoryInterface
   */
  protected $configFactory;

  /**
   * Constructs a new Fast404ExceptionHtmlSubscriber.
   *
   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
   *   The configuration factory.
   * @param \Symfony\Component\HttpKernel\HttpKernelInterface $http_kernel
   *   The HTTP Kernel service.
   */
  public function __construct(ConfigFactoryInterface $config_factory, HttpKernelInterface $http_kernel) {
    $this->configFactory = $config_factory;
    $this->httpKernel = $http_kernel;
  }

  /**
   * {@inheritdoc}
   */
  protected static function getPriority() {

    // A very high priority so that it can take precedent over anything else,
    // and thus be fast.
    return 200;
  }

  /**
   * {@inheritdoc}
   */
  protected function getHandledFormats() {
    return [
      'html',
    ];
  }

  /**
   * Handles a 404 error for HTML.
   *
   * @param \Symfony\Component\HttpKernel\Event\GetResponseForExceptionEvent $event
   *   The event to process.
   */
  public function on404(GetResponseForExceptionEvent $event) {
    $request = $event
      ->getRequest();
    $config = $this->configFactory
      ->get('system.performance');
    $exclude_paths = $config
      ->get('fast_404.exclude_paths');
    if ($config
      ->get('fast_404.enabled') && $exclude_paths && !preg_match($exclude_paths, $request
      ->getPathInfo())) {
      $fast_paths = $config
        ->get('fast_404.paths');
      if ($fast_paths && preg_match($fast_paths, $request
        ->getPathInfo())) {
        $fast_404_html = strtr($config
          ->get('fast_404.html'), [
          '@path' => Html::escape($request
            ->getUri()),
        ]);
        $response = new Response($fast_404_html, Response::HTTP_NOT_FOUND);
        $event
          ->setResponse($response);
      }
    }
  }

}

Members

Name	Modifiers	Type	Description	Overrides
Fast404ExceptionHtmlSubscriber::$configFactory	protected	property	The config factory.
Fast404ExceptionHtmlSubscriber::$httpKernel	protected	property	The HTTP kernel.
Fast404ExceptionHtmlSubscriber::getHandledFormats	protected	function	Specifies the request formats this subscriber will respond to. Overrides HttpExceptionSubscriberBase::getHandledFormats
Fast404ExceptionHtmlSubscriber::getPriority	protected static	function	Specifies the priority of all listeners in this class. Overrides HttpExceptionSubscriberBase::getPriority
Fast404ExceptionHtmlSubscriber::on404	public	function	Handles a 404 error for HTML.
Fast404ExceptionHtmlSubscriber::__construct	public	function	Constructs a new Fast404ExceptionHtmlSubscriber.
HttpExceptionSubscriberBase::getSubscribedEvents	public static	function	Registers the methods in this class that should be listeners.
HttpExceptionSubscriberBase::onException	public	function	Handles errors for this subscriber.