diff core/lib/Drupal/Core/EventSubscriber/CustomPageExceptionHtmlSubscriber.php @ 0:4c8ae668cc8c

Initial import (non-working)

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/core/lib/Drupal/Core/EventSubscriber/CustomPageExceptionHtmlSubscriber.php	Wed Nov 29 16:09:58 2017 +0000
@@ -0,0 +1,122 @@
+<?php
+
+namespace Drupal\Core\EventSubscriber;
+
+use Drupal\Core\Access\AccessManagerInterface;
+use Drupal\Core\Cache\RefinableCacheableDependencyInterface;
+use Drupal\Core\Config\ConfigFactoryInterface;
+use Drupal\Core\Routing\AccessAwareRouterInterface;
+use Drupal\Core\Routing\RedirectDestinationInterface;
+use Drupal\Core\Url;
+use Psr\Log\LoggerInterface;
+use Symfony\Component\HttpFoundation\Response;
+use Symfony\Component\HttpKernel\Event\GetResponseForExceptionEvent;
+use Symfony\Component\HttpKernel\HttpKernelInterface;
+use Symfony\Component\Routing\Matcher\UrlMatcherInterface;
+
+/**
+ * Exception subscriber for handling core custom HTML error pages.
+ */
+class CustomPageExceptionHtmlSubscriber extends DefaultExceptionHtmlSubscriber {
+
+  /**
+   * The configuration factory.
+   *
+   * @var \Drupal\Core\Config\ConfigFactoryInterface
+   */
+  protected $configFactory;
+
+  /**
+   * The access manager.
+   *
+   * @var \Drupal\Core\Access\AccessManagerInterface
+   */
+  protected $accessManager;
+
+  /**
+   * Constructs a new CustomPageExceptionHtmlSubscriber.
+   *
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
+   *   The configuration factory.
+   * @param \Symfony\Component\HttpKernel\HttpKernelInterface $http_kernel
+   *   The HTTP Kernel service.
+   * @param \Psr\Log\LoggerInterface $logger
+   *   The logger service.
+   * @param \Drupal\Core\Routing\RedirectDestinationInterface $redirect_destination
+   *   The redirect destination service.
+   * @param \Symfony\Component\Routing\Matcher\UrlMatcherInterface $access_unaware_router
+   *   A router implementation which does not check access.
+   * @param \Drupal\Core\Access\AccessManagerInterface $access_manager
+   *   The access manager.
+   */
+  public function __construct(ConfigFactoryInterface $config_factory, HttpKernelInterface $http_kernel, LoggerInterface $logger, RedirectDestinationInterface $redirect_destination, UrlMatcherInterface $access_unaware_router, AccessManagerInterface $access_manager) {
+    parent::__construct($http_kernel, $logger, $redirect_destination, $access_unaware_router);
+    $this->configFactory = $config_factory;
+    $this->accessManager = $access_manager;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected static function getPriority() {
+    return -50;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function on403(GetResponseForExceptionEvent $event) {
+    $custom_403_path = $this->configFactory->get('system.site')->get('page.403');
+    if (!empty($custom_403_path)) {
+      $this->makeSubrequestToCustomPath($event, $custom_403_path, Response::HTTP_FORBIDDEN);
+    }
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function on404(GetResponseForExceptionEvent $event) {
+    $custom_404_path = $this->configFactory->get('system.site')->get('page.404');
+    if (!empty($custom_404_path)) {
+      $this->makeSubrequestToCustomPath($event, $custom_404_path, Response::HTTP_NOT_FOUND);
+    }
+  }
+
+  /**
+   * Makes a subrequest to retrieve the custom error page.
+   *
+   * @param \Symfony\Component\HttpKernel\Event\GetResponseForExceptionEvent $event
+   *   The event to process.
+   * @param string $custom_path
+   *   The custom path to which to make a subrequest for this error message.
+   * @param int $status_code
+   *   The status code for the error being handled.
+   */
+  protected function makeSubrequestToCustomPath(GetResponseForExceptionEvent $event, $custom_path, $status_code) {
+    $url = Url::fromUserInput($custom_path);
+    if ($url->isRouted()) {
+      $access_result = $this->accessManager->checkNamedRoute($url->getRouteName(), $url->getRouteParameters(), NULL, TRUE);
+      $request = $event->getRequest();
+
+      // Merge the custom path's route's access result's cacheability metadata
+      // with the existing one (from the master request), otherwise create it.
+      if (!$request->attributes->has(AccessAwareRouterInterface::ACCESS_RESULT)) {
+        $request->attributes->set(AccessAwareRouterInterface::ACCESS_RESULT, $access_result);
+      }
+      else {
+        $existing_access_result = $request->attributes->get(AccessAwareRouterInterface::ACCESS_RESULT);
+        if ($existing_access_result instanceof RefinableCacheableDependencyInterface) {
+          $existing_access_result->addCacheableDependency($access_result);
+        }
+      }
+
+      // Only perform the subrequest if the custom path is actually accessible.
+      if (!$access_result->isAllowed()) {
+        return;
+      }
+    }
+
+    $this->makeSubrequest($event, $custom_path, $status_code);
+  }
+
+}