Chris@0: <?php
Chris@0: 
Chris@0: namespace Drupal\node\EventSubscriber;
Chris@0: 
Chris@0: use Drupal\Core\KeyValueStore\KeyValueFactoryInterface;
Chris@0: use Drupal\Core\Language\LanguageManagerInterface;
Chris@0: use Drupal\Core\ParamConverter\ParamNotConvertedException;
Chris@0: use Drupal\Core\Routing\UrlGeneratorInterface;
Chris@0: use Drupal\Core\State\StateInterface;
Chris@0: use Symfony\Component\EventDispatcher\EventSubscriberInterface;
Chris@0: use Symfony\Component\HttpFoundation\RedirectResponse;
Chris@0: use Symfony\Component\HttpKernel\Event\GetResponseForExceptionEvent;
Chris@0: use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
Chris@0: use Symfony\Component\HttpKernel\KernelEvents;
Chris@0: 
Chris@0: /**
Chris@0:  * Redirect node translations that have been consolidated by migration.
Chris@0:  *
Chris@0:  * If we migrated node translations from Drupal 6 or 7, these nodes are now
Chris@0:  * combined with their source language node. Since there still might be
Chris@0:  * references to the URLs of these now consolidated nodes, this service catches
Chris@0:  * the 404s and try to redirect them to the right node in the right language.
Chris@0:  *
Chris@0:  * The mapping of the old nids to the new ones is made by the
Chris@0:  * NodeTranslationMigrateSubscriber class during the migration and is stored
Chris@0:  * in the "node_translation_redirect" key/value collection.
Chris@0:  *
Chris@0:  * @see \Drupal\node\NodeServiceProvider
Chris@0:  * @see \Drupal\node\EventSubscriber\NodeTranslationMigrateSubscriber
Chris@0:  */
Chris@0: class NodeTranslationExceptionSubscriber implements EventSubscriberInterface {
Chris@0: 
Chris@0:   /**
Chris@0:    * The key value factory.
Chris@0:    *
Chris@0:    * @var \Drupal\Core\KeyValueStore\KeyValueFactoryInterface
Chris@0:    */
Chris@0:   protected $keyValue;
Chris@0: 
Chris@0:   /**
Chris@0:    * The language manager.
Chris@0:    *
Chris@0:    * @var \Drupal\Core\Language\LanguageManagerInterface
Chris@0:    */
Chris@0:   protected $languageManager;
Chris@0: 
Chris@0:   /**
Chris@0:    * The URL generator.
Chris@0:    *
Chris@0:    * @var \Drupal\Core\Routing\UrlGeneratorInterface
Chris@0:    */
Chris@0:   protected $urlGenerator;
Chris@0: 
Chris@0:   /**
Chris@0:    * The state service.
Chris@0:    *
Chris@0:    * @var \Drupal\Core\State\StateInterface
Chris@0:    */
Chris@0:   protected $state;
Chris@0: 
Chris@0:   /**
Chris@0:    * Constructs the NodeTranslationExceptionSubscriber.
Chris@0:    *
Chris@0:    * @param \Drupal\Core\KeyValueStore\KeyValueFactoryInterface $key_value
Chris@0:    *   The key value factory.
Chris@0:    * @param \Drupal\Core\Language\LanguageManagerInterface $language_manager
Chris@0:    *   The language manager.
Chris@0:    * @param \Drupal\Core\Routing\UrlGeneratorInterface $url_generator
Chris@0:    *   The URL generator.
Chris@0:    * @param \Drupal\Core\State\StateInterface $state
Chris@0:    *   The state service.
Chris@0:    */
Chris@0:   public function __construct(KeyValueFactoryInterface $key_value, LanguageManagerInterface $language_manager, UrlGeneratorInterface $url_generator, StateInterface $state) {
Chris@0:     $this->keyValue = $key_value;
Chris@0:     $this->languageManager = $language_manager;
Chris@0:     $this->urlGenerator = $url_generator;
Chris@0:     $this->state = $state;
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Redirects not found node translations using the key value collection.
Chris@0:    *
Chris@0:    * @param \Symfony\Component\HttpKernel\Event\GetResponseForExceptionEvent $event
Chris@0:    *   The exception event.
Chris@0:    */
Chris@0:   public function onException(GetResponseForExceptionEvent $event) {
Chris@0:     $exception = $event->getException();
Chris@0: 
Chris@0:     // If this is not a 404, we don't need to check for a redirection.
Chris@0:     if (!($exception instanceof NotFoundHttpException)) {
Chris@0:       return;
Chris@0:     }
Chris@0: 
Chris@0:     $previous_exception = $exception->getPrevious();
Chris@0:     if ($previous_exception instanceof ParamNotConvertedException) {
Chris@0:       $route_name = $previous_exception->getRouteName();
Chris@0:       $parameters = $previous_exception->getRawParameters();
Chris@0:       if ($route_name === 'entity.node.canonical' && isset($parameters['node'])) {
Chris@0:         // If the node_translation_redirect state is not set, we don't need to check
Chris@0:         // for a redirection.
Chris@0:         if (!$this->state->get('node_translation_redirect')) {
Chris@0:           return;
Chris@0:         }
Chris@0:         $old_nid = $parameters['node'];
Chris@0:         $collection = $this->keyValue->get('node_translation_redirect');
Chris@0:         if ($old_nid && $value = $collection->get($old_nid)) {
Chris@0:           list($nid, $langcode) = $value;
Chris@0:           $language = $this->languageManager->getLanguage($langcode);
Chris@0:           $url = $this->urlGenerator->generateFromRoute('entity.node.canonical', ['node' => $nid], ['language' => $language]);
Chris@0:           $response = new RedirectResponse($url, 301);
Chris@0:           $event->setResponse($response);
Chris@0:         }
Chris@0:       }
Chris@0:     }
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public static function getSubscribedEvents() {
Chris@0:     $events = [];
Chris@0: 
Chris@0:     $events[KernelEvents::EXCEPTION] = ['onException'];
Chris@0: 
Chris@0:     return $events;
Chris@0:   }
Chris@0: 
Chris@0: }