o365-2.0.3/modules/o365_sso/src/EventSubscriber/RouteSubscriber.php

<?php

namespace Drupal\o365_sso\EventSubscriber;

use Drupal\Core\Routing\RouteSubscriberBase;
use Drupal\Core\Routing\RoutingEvents;
use Symfony\Component\Routing\RouteCollection;

/**
 * Route subscriber for the custom logout functionality.
 */
final class RouteSubscriber extends RouteSubscriberBase {

  /**
   * {@inheritdoc}
   */
  public static function getSubscribedEvents(): array {
    $events = parent::getSubscribedEvents();
    $events[RoutingEvents::ALTER] = ['onAlterRoutes', -300];
    return $events;
  }

  /**
   * Alter the logout route.
   *
   * @param \Symfony\Component\Routing\RouteCollection $collection
   *   The route collection.
   */
  protected function alterRoutes(RouteCollection $collection) {
    if ($route = $collection->get('user.logout')) {
      $route->setDefaults([
        '_controller' => '\Drupal\o365_sso\Controller\LogoutController::logout',
      ]);
    }
  }

}