lupus_decoupled-1.x-dev/modules/lupus_decoupled_ce_api/src/EventSubscriber/FrontendRedirectSubscriber.php

<?php

namespace Drupal\lupus_decoupled_ce_api\EventSubscriber;

use Drupal\Core\Cache\CacheableResponseInterface;
use Drupal\Core\Config\ConfigFactoryInterface;
use Drupal\Core\Entity\EntityInterface;
use Drupal\Core\Routing\TrustedRedirectResponse;
use Drupal\lupus_decoupled_ce_api\BaseUrlProviderTrait;
use Drupal\lupus_decoupled_ce_api\LupusDecoupledCeApiSettingsTrait;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;
use Symfony\Component\HttpKernel\Event\RequestEvent;
use Symfony\Component\HttpKernel\Event\ResponseEvent;
use Symfony\Component\HttpKernel\KernelEvents;
use drunomics\ServiceUtils\Core\Routing\CurrentRouteMatchTrait;
use drunomics\ServiceUtils\Symfony\HttpFoundation\RequestStackTrait;

/**
 * Redirects routes to the decoupled frontend when access without /ce-api.
 */
class FrontendRedirectSubscriber implements EventSubscriberInterface {

  use BaseUrlProviderTrait;
  use CurrentRouteMatchTrait;
  use LupusDecoupledCeApiSettingsTrait;
  use RequestStackTrait;

  /**
   * An array of routes to redirect to the frontend.
   *
   * Contains 'entity.node.canonical' and possibly others.
   *
   * If a new route is added to frontend_routes,
   * also add its path to lupus_decoupled_ce_api.frontend_paths.
   * You can register a new frontend route by implementing
   * a custom service provider.
   *
   * @var string[]
   */
  protected $frontendRoutes;

  /**
   * The config factory service.
   *
   * @var \Drupal\Core\Config\ConfigFactoryInterface
   */
  protected $configFactory;

  /**
   * FrontendRedirectSubscriber constructor.
   *
   * @param \Drupal\Core\Config\ConfigFactoryInterface $configFactory
   *   The config factory service.
   * @param string[] $frontendRoutes
   *   The routes to redirect.
   */
  public function __construct(ConfigFactoryInterface $configFactory, array $frontendRoutes) {
    $this->configFactory = $configFactory;
    $this->frontendRoutes = $frontendRoutes;
  }

  /**
   * Redirects frontend routes to the frontend base URL.
   *
   * @param \Symfony\Component\HttpKernel\Event\RequestEvent $event
   *   The request event.
   */
  public function onKernelRequest(RequestEvent $event) {
    if ($this->getCurrentRequest()->getRequestFormat() != 'html') {
      // Do not redirect API responses.
      return;
    }

    if ($this->getBaseUrlProvider()->getFrontendBaseUrl() == NULL || !$this->getLupusDecoupledCeApiSettings()->get('frontend_routes_redirect')) {
      // Exit if frontend_base_url is not set
      // or if frontend redirect is disabled.
      return;
    }

    if (in_array($this->getCurrentRouteMatch()->getRouteName(), $this->frontendRoutes)
      && ($event->getRequest()->getMethod()) != 'POST') {
      $route_match = $this->getCurrentRouteMatch();
      $redirect_url = NULL;
      // For entity routes, get entity-specific frontend base URLs.
      if (preg_match('/entity\.[a-z]+\.canonical/', $route_match->getRouteName())) {
        $parameters = $route_match->getParameters()->all();
        $entity = reset($parameters);
        if ($entity && $entity instanceof EntityInterface) {
          $options['query'] = $this->requestStack->getCurrentRequest()->query->all();
          $options['absolute'] = TRUE;
          $redirect_url = $entity->toUrl('canonical', $options)->toString();
        }
      }
      // For other routes just forward to the frontend by keeping the current
      // request URL.
      if (!isset($redirect_url)) {
        if ($frontend_base_url = $this->getBaseUrlProvider()->getFrontendBaseUrl()) {
          // For sites with more than one frontend url there this method has to
          // be overridden and a mechanism to decide frontend url
          // should be put in place.
          $redirect_url = $frontend_base_url . $this->getCurrentRequest()->getRequestUri();
        }
      }

      if (isset($redirect_url)) {
        // Prevent Core's RedirectResponseSubscriber from redirecting back
        // to the original request's destination, ignoring our response.
        $request_query_parameters = $this->requestStack->getCurrentRequest()->query;
        $destination = $request_query_parameters->get('destination');
        if ($destination) {
          $request_query_parameters->remove('destination');
        }

        // Set the redirect response.
        $event->setResponse(new TrustedRedirectResponse($redirect_url));
        $event->stopPropagation();
      }
    }
  }

  /**
   * Handles the response.
   *
   * @param \Symfony\Component\HttpKernel\Event\ResponseEvent $event
   *   The event to process.
   */
  public function onResponse(ResponseEvent $event) {
    $response = $event->getResponse();
    if ($response instanceof CacheableResponseInterface) {
      $response->addCacheableDependency($this->getLupusDecoupledCeApiSettings());
    }
  }

  /**
   * {@inheritdoc}
   */
  public static function getSubscribedEvents() {
    return [
      KernelEvents::REQUEST => ['onKernelRequest', 0],
      KernelEvents::RESPONSE => ['onResponse', 5],
    ];
  }

}