class MainContentViewSubscriber in Drupal 9

View subscriber rendering main content render arrays into responses.

Additional target rendering formats can be defined by adding another service that implements \Drupal\Core\Render\MainContent\MainContentRendererInterface and tagging it as a

render . main_content_renderer;

, then \Drupal\Core\Render\MainContent\MainContentRenderersPass will detect it and use it when appropriate.

Hierarchy

• class \Drupal\Core\EventSubscriber\MainContentViewSubscriber implements \Symfony\Component\EventDispatcher\EventSubscriberInterface

See also

\Drupal\Core\Render\MainContent\MainContentRendererInterface

\Drupal\Core\Render\MainContentControllerPass

28 files declare their use of MainContentViewSubscriber

AjaxHelperTrait.php in core/lib/Drupal/Core/Ajax/AjaxHelperTrait.php

AreaDisplayLinkTest.php in core/modules/views/tests/src/Kernel/Handler/AreaDisplayLinkTest.php

BlockLibraryController.php in core/modules/block/src/Controller/BlockLibraryController.php

ContentModerationConfigureEntityTypesForm.php in core/modules/content_moderation/src/Form/ContentModerationConfigureEntityTypesForm.php

DisplayLink.php in core/modules/views/src/Plugin/views/area/DisplayLink.php

... See full list

1 string reference to 'MainContentViewSubscriber'

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

core/core.services.yml

1 service uses MainContentViewSubscriber

main_content_view_subscriber in core/core.services.yml

Drupal\Core\EventSubscriber\MainContentViewSubscriber

File

core/lib/Drupal/Core/EventSubscriber/MainContentViewSubscriber.php, line 25

Namespace

Drupal\Core\EventSubscriber

class MainContentViewSubscriber implements EventSubscriberInterface {

  /**
   * The class resolver service.
   *
   * @var \Drupal\Core\Controller\ControllerResolverInterface
   */
  protected $classResolver;

  /**
   * The current route match.
   *
   * @var \Drupal\Core\Routing\RouteMatchInterface
   */
  protected $routeMatch;

  /**
   * The available main content renderer services, keyed per format.
   *
   * @var array
   */
  protected $mainContentRenderers;

  /**
   * URL query attribute to indicate the wrapper used to render a request.
   *
   * The wrapper format determines how the HTML is wrapped, for example in a
   * modal dialog.
   */
  const WRAPPER_FORMAT = '_wrapper_format';

  /**
   * Constructs a new MainContentViewSubscriber object.
   *
   * @param \Drupal\Core\DependencyInjection\ClassResolverInterface $class_resolver
   *   The class resolver service.
   * @param \Drupal\Core\Routing\RouteMatchInterface $route_match
   *   The current route match.
   * @param array $main_content_renderers
   *   The available main content renderer service IDs, keyed by format.
   */
  public function __construct(ClassResolverInterface $class_resolver, RouteMatchInterface $route_match, array $main_content_renderers) {
    $this->classResolver = $class_resolver;
    $this->routeMatch = $route_match;
    $this->mainContentRenderers = $main_content_renderers;
  }

  /**
   * Sets a response given a (main content) render array.
   *
   * @param \Symfony\Component\HttpKernel\Event\ViewEvent $event
   *   The event to process.
   */
  public function onViewRenderArray(ViewEvent $event) {
    $request = $event
      ->getRequest();
    $result = $event
      ->getControllerResult();

    // Render the controller result into a response if it's a render array.
    if (is_array($result) && ($request->query
      ->has(static::WRAPPER_FORMAT) || $request
      ->getRequestFormat() == 'html')) {
      $wrapper = $request->query
        ->get(static::WRAPPER_FORMAT, 'html');

      // Fall back to HTML if the requested wrapper envelope is not available.
      $wrapper = isset($this->mainContentRenderers[$wrapper]) ? $wrapper : 'html';
      $renderer = $this->classResolver
        ->getInstanceFromDefinition($this->mainContentRenderers[$wrapper]);
      $response = $renderer
        ->renderResponse($result, $request, $this->routeMatch);

      // The main content render array is rendered into a different Response
      // object, depending on the specified wrapper format.
      if ($response instanceof CacheableResponseInterface) {
        $main_content_view_subscriber_cacheability = (new CacheableMetadata())
          ->setCacheContexts([
          'url.query_args:' . static::WRAPPER_FORMAT,
        ]);
        $response
          ->addCacheableDependency($main_content_view_subscriber_cacheability);
      }
      $event
        ->setResponse($response);
    }
  }

  /**
   * {@inheritdoc}
   */
  public static function getSubscribedEvents() {
    $events[KernelEvents::VIEW][] = [
      'onViewRenderArray',
    ];
    return $events;
  }

}

Members

Name	Modifiers	Type	Description	Overrides
MainContentViewSubscriber::$classResolver	protected	property	The class resolver service.
MainContentViewSubscriber::$mainContentRenderers	protected	property	The available main content renderer services, keyed per format.
MainContentViewSubscriber::$routeMatch	protected	property	The current route match.
MainContentViewSubscriber::getSubscribedEvents	public static	function
MainContentViewSubscriber::onViewRenderArray	public	function	Sets a response given a (main content) render array.
MainContentViewSubscriber::WRAPPER_FORMAT		constant	URL query attribute to indicate the wrapper used to render a request.
MainContentViewSubscriber::__construct	public	function	Constructs a new MainContentViewSubscriber object.