class PathSubscriber

class PathSubscriber implements EventSubscriberInterface {
    
    /**
     * The alias manager that caches alias lookups based on the request.
     *
     * @var \Drupal\Core\Path\AliasManagerInterface
     */
    protected $aliasManager;
    
    /**
     * The current path.
     *
     * @var \Drupal\Core\Path\CurrentPathStack
     */
    protected $currentPath;
    
    /**
     * Constructs a new PathSubscriber instance.
     *
     * @param \Drupal\Core\Path\AliasManagerInterface $alias_manager
     *   The alias manager.
     * @param \Drupal\Core\Path\CurrentPathStack $current_path
     *   The current path.
     */
    public function __construct(AliasManagerInterface $alias_manager, CurrentPathStack $current_path) {
        $this->aliasManager = $alias_manager;
        $this->currentPath = $current_path;
        // This is used as base class by the new class, so we do not trigger
        // deprecation notices when that or any child class is instantiated.
        $new_class = 'Drupal\\path_alias\\EventSubscriber\\PathAliasSubscriber';
        if (!is_a($this, $new_class) && class_exists($new_class)) {
            @trigger_error('The \\' . __CLASS__ . ' class is deprecated in drupal:8.8.0 and is removed from drupal:9.0.0. Instead, use \\' . $new_class . '. See https://drupal.org/node/3092086', E_USER_DEPRECATED);
        }
    }
    
    /**
     * Sets the cache key on the alias manager cache decorator.
     *
     * KernelEvents::CONTROLLER is used in order to be executed after routing.
     *
     * @param \Symfony\Component\HttpKernel\Event\FilterControllerEvent $event
     *   The Event to process.
     */
    public function onKernelController(FilterControllerEvent $event) {
        // Set the cache key on the alias manager cache decorator.
        if ($event->isMasterRequest()) {
            $this->aliasManager
                ->setCacheKey(rtrim($this->currentPath
                ->getPath($event->getRequest()), '/'));
        }
    }
    
    /**
     * Ensures system paths for the request get cached.
     */
    public function onKernelTerminate(PostResponseEvent $event) {
        $this->aliasManager
            ->writeCache();
    }
    
    /**
     * Registers the methods in this class that should be listeners.
     *
     * @return array
     *   An array of event listener definitions.
     */
    public static function getSubscribedEvents() {
        $events[KernelEvents::CONTROLLER][] = [
            'onKernelController',
            200,
        ];
        $events[KernelEvents::TERMINATE][] = [
            'onKernelTerminate',
            200,
        ];
        return $events;
    }

}