services:

  example.standard_access_checker:

    class: Drupal\example\Access\StandardAccessCheck

    arguments: ['@current_user']

    tags:

      - { name: access_check, applies_to: _custom_access }

  example.services_access_checker:

    class: Drupal\example\Access\ServicesAccessCheck

    arguments: ['@mymodule.service']

    tags:

      - { name: access_check }

namespace Drupal\example\Routing;

​

use Drupal\Core\Routing\RouteSubscriberBase;

use Symfony\Component\Routing\RouteCollection;

​

/**

 * Listens to the dynamic route events.

 */

class RouteSubscriber extends RouteSubscriberBase {

​

  /**

   * {@inheritdoc}

   */

  protected function alterRoutes(RouteCollection $collection) {

    // Define custom access for '/user/login'.

    if ($route = $collection->get('user.login')) {

      $route->setRequirement('_custom_access', 'Drupal\example\Access\StandardAccessCheck::access');

    }

    // Define custom access for '/user/logout'.

    if ($route = $collection->get('user.logout')) {

      $route->setRequirement('_custom_access', 'example.services_access_checker::access');

    }

  }

​

}