class KernelDestructionSubscriber in Drupal 8

Destructs services that are initiated and tagged with "needs_destruction".

Hierarchy

• class \Drupal\Core\EventSubscriber\KernelDestructionSubscriber implements \Symfony\Component\EventDispatcher\EventSubscriberInterface, \Symfony\Component\DependencyInjection\ContainerAwareInterface uses \Symfony\Component\DependencyInjection\ContainerAwareTrait

See also

\Drupal\Core\DestructableInterface

1 string reference to 'KernelDestructionSubscriber'

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

core/core.services.yml

1 service uses KernelDestructionSubscriber

kernel_destruct_subscriber in core/core.services.yml

Drupal\Core\EventSubscriber\KernelDestructionSubscriber

File

core/lib/Drupal/Core/EventSubscriber/KernelDestructionSubscriber.php, line 16

Namespace

Drupal\Core\EventSubscriber

class KernelDestructionSubscriber implements EventSubscriberInterface, ContainerAwareInterface {
  use ContainerAwareTrait;

  /**
   * Holds an array of service ID's that will require destruction.
   *
   * @var array
   */
  protected $services = [];

  /**
   * Registers a service for destruction.
   *
   * Calls to this method are set up in
   * RegisterServicesForDestructionPass::process().
   *
   * @param string $id
   *   Name of the service.
   */
  public function registerService($id) {
    $this->services[] = $id;
  }

  /**
   * Invoked by the terminate kernel event.
   *
   * @param \Symfony\Component\HttpKernel\Event\PostResponseEvent $event
   *   The event object.
   */
  public function onKernelTerminate(PostResponseEvent $event) {
    foreach ($this->services as $id) {

      // Check if the service was initialized during this request, destruction
      // is not necessary if the service was not used.
      if ($this->container
        ->initialized($id)) {
        $service = $this->container
          ->get($id);
        $service
          ->destruct();
      }
    }
  }

  /**
   * Registers the methods in this class that should be listeners.
   *
   * @return array
   *   An array of event listener definitions.
   */
  public static function getSubscribedEvents() {
    $events[KernelEvents::TERMINATE][] = [
      'onKernelTerminate',
      100,
    ];
    return $events;
  }

}

Members

Name	Modifiers	Type	Description	Overrides
KernelDestructionSubscriber::$services	protected	property	Holds an array of service ID's that will require destruction.
KernelDestructionSubscriber::getSubscribedEvents	public static	function	Registers the methods in this class that should be listeners.
KernelDestructionSubscriber::onKernelTerminate	public	function	Invoked by the terminate kernel event.
KernelDestructionSubscriber::registerService	public	function	Registers a service for destruction.