class NodeViewController in Drupal 8

Defines a controller to render a single node.

Hierarchy

• class \Drupal\Core\Entity\Controller\EntityViewController implements ContainerInjectionInterface, TrustedCallbackInterface uses DeprecatedServicePropertyTrait
  • class \Drupal\node\Controller\NodeViewController

File

core/modules/node/src/Controller/NodeViewController.php, line 16

Namespace

Drupal\node\Controller

class NodeViewController extends EntityViewController {

  /**
   * The current user.
   *
   * @var \Drupal\Core\Session\AccountInterface
   */
  protected $currentUser;

  /**
   * The entity repository service.
   *
   * @var \Drupal\Core\Entity\EntityRepositoryInterface
   */
  protected $entityRepository;

  /**
   * Creates an NodeViewController object.
   *
   * @param \Drupal\Core\Entity\EntityTypeManagerInterface $entity_type_manager
   *   The entity type manager.
   * @param \Drupal\Core\Render\RendererInterface $renderer
   *   The renderer service.
   * @param \Drupal\Core\Session\AccountInterface $current_user
   *   The current user. For backwards compatibility this is optional, however
   *   this will be removed before Drupal 9.0.0.
   * @param \Drupal\Core\Entity\EntityRepositoryInterface $entity_repository
   *   The entity repository.
   */
  public function __construct(EntityTypeManagerInterface $entity_type_manager, RendererInterface $renderer, AccountInterface $current_user = NULL, EntityRepositoryInterface $entity_repository = NULL) {
    parent::__construct($entity_type_manager, $renderer);
    $this->currentUser = $current_user ?: \Drupal::currentUser();
    if (!$entity_repository) {
      @trigger_error('The entity.repository service must be passed to NodeViewController::__construct(), it is required before Drupal 9.0.0. See https://www.drupal.org/node/2549139.', E_USER_DEPRECATED);
      $entity_repository = \Drupal::service('entity.repository');
    }
    $this->entityRepository = $entity_repository;
  }

  /**
   * {@inheritdoc}
   */
  public static function create(ContainerInterface $container) {
    return new static($container
      ->get('entity_type.manager'), $container
      ->get('renderer'), $container
      ->get('current_user'), $container
      ->get('entity.repository'));
  }

  /**
   * {@inheritdoc}
   */
  public function view(EntityInterface $node, $view_mode = 'full', $langcode = NULL) {
    $build = parent::view($node, $view_mode, $langcode);
    foreach ($node
      ->uriRelationships() as $rel) {
      $url = $node
        ->toUrl($rel)
        ->setAbsolute(TRUE);

      // Add link relationships if the user is authenticated or if the anonymous
      // user has access. Access checking must be done for anonymous users to
      // avoid traffic to inaccessible pages from web crawlers. For
      // authenticated users, showing the links in HTML head does not impact
      // user experience or security, since the routes are access checked when
      // visited and only visible via view source. This prevents doing
      // potentially expensive and hard to cache access checks on every request.
      // This means that the page will vary by user.permissions. We also rely on
      // the access checking fallback to ensure the correct cacheability
      // metadata if we have to check access.
      if ($this->currentUser
        ->isAuthenticated() || $url
        ->access($this->currentUser)) {

        // Set the node path as the canonical URL to prevent duplicate content.
        $build['#attached']['html_head_link'][] = [
          [
            'rel' => $rel,
            'href' => $url
              ->toString(),
          ],
          TRUE,
        ];
      }
      if ($rel == 'canonical') {

        // Set the non-aliased canonical path as a default shortlink.
        $build['#attached']['html_head_link'][] = [
          [
            'rel' => 'shortlink',
            'href' => $url
              ->setOption('alias', TRUE)
              ->toString(),
          ],
          TRUE,
        ];
      }
    }

    // Since this generates absolute URLs, it can only be cached "per site".
    $build['#cache']['contexts'][] = 'url.site';

    // Given this varies by $this->currentUser->isAuthenticated(), add a cache
    // context based on the anonymous role.
    $build['#cache']['contexts'][] = 'user.roles:anonymous';
    return $build;
  }

  /**
   * The _title_callback for the page that renders a single node.
   *
   * @param \Drupal\Core\Entity\EntityInterface $node
   *   The current node.
   *
   * @return string
   *   The page title.
   */
  public function title(EntityInterface $node) {
    return $this->entityRepository
      ->getTranslationFromContext($node)
      ->label();
  }

}

Members

Name	Modifiers	Type	Description	Overrides
DeprecatedServicePropertyTrait::__get	public	function	Allows to access deprecated/removed properties.
EntityViewController::$deprecatedProperties	protected	property
EntityViewController::$entityTypeManager	protected	property	The entity type manager.
EntityViewController::$renderer	protected	property	The renderer service.
EntityViewController::buildTitle	public	function	Pre-render callback to build the page title.
EntityViewController::trustedCallbacks	public static	function	Lists the trusted callbacks provided by the implementing class. Overrides TrustedCallbackInterface::trustedCallbacks
EntityViewController::viewRevision	public	function	Provides a page to render a single entity revision.
NodeViewController::$currentUser	protected	property	The current user.
NodeViewController::$entityRepository	protected	property	The entity repository service.
NodeViewController::create	public static	function	Instantiates a new instance of this class. Overrides EntityViewController::create
NodeViewController::title	public	function	The _title_callback for the page that renders a single node.
NodeViewController::view	public	function	Provides a page to render a single entity. Overrides EntityViewController::view
NodeViewController::__construct	public	function	Creates an NodeViewController object. Overrides EntityViewController::__construct
TrustedCallbackInterface::THROW_EXCEPTION		constant	Untrusted callbacks throw exceptions.
TrustedCallbackInterface::TRIGGER_SILENCED_DEPRECATION		constant	Untrusted callbacks trigger silenced E_USER_DEPRECATION errors.
TrustedCallbackInterface::TRIGGER_WARNING		constant	Untrusted callbacks trigger E_USER_WARNING errors.