vendor/contao/core-bundle/src/EventListener/PreviewToolbarListener.php line 64

Open in your IDE?
  1. <?php
  3. declare(strict_types=1);
  5. /*
  6.  * This file is part of Contao.
  7.  *
  8.  * (c) Leo Feyer
  9.  *
  10.  * @license LGPL-3.0-or-later
  11.  */
  13. namespace Contao\CoreBundle\EventListener;
  15. use Contao\CoreBundle\Routing\ScopeMatcher;
  16. use Symfony\Component\HttpFoundation\Request;
  17. use Symfony\Component\HttpFoundation\Response;
  18. use Symfony\Component\HttpKernel\Event\ResponseEvent;
  19. use Symfony\Component\Routing\RouterInterface;
  20. use Twig\Environment as TwigEnvironment;
  21. use Twig\Error\Error as TwigError;
  23. /**
  24.  * Injects the back end preview toolbar on any response within the /preview.php
  25.  * entry point.
  26.  *
  27.  * The onKernelResponse method must be connected to the kernel.response event.
  28.  *
  29.  * The toolbar is only injected on well-formed HTML with a proper </body> tag,
  30.  * so is never included in sub-requests or ESI requests.
  31.  *
  32.  * @internal
  33.  */
  34. class PreviewToolbarListener
  35. {
  36.     /**
  37.      * @var ScopeMatcher
  38.      */
  39.     private $scopeMatcher;
  41.     /**
  42.      * @var TwigEnvironment
  43.      */
  44.     private $twig;
  46.     /**
  47.      * @var RouterInterface
  48.      */
  49.     private $router;
  51.     /**
  52.      * @var string
  53.      */
  54.     private $previewScript;
  56.     public function __construct(ScopeMatcher $scopeMatcher, TwigEnvironment $twig, RouterInterface $router, string $previewScript = '')
  57.     {
  58.         $this->scopeMatcher = $scopeMatcher;
  59.         $this->twig = $twig;
  60.         $this->router = $router;
  61.         $this->previewScript = $previewScript;
  62.     }
  64.     public function __invoke(ResponseEvent $event): void
  65.     {
  66.         if ($this->scopeMatcher->isBackendMasterRequest($event)) {
  67.             return;
  68.         }
  70.         $request = $event->getRequest();
  71.         $response = $event->getResponse();
  73.         // Do not capture redirects, errors, or modify XML HTTP Requests
  74.         if (
  75.             !$request->attributes->get('_preview', false)
  76.             || $request->isXmlHttpRequest()
  77.             || !($response->isSuccessful() || $response->isClientError())
  78.         ) {
  79.             return;
  80.         }
  82.         // Only inject the toolbar into HTML responses
  83.         if (
  84.             'html' !== $request->getRequestFormat()
  85.             || false === strpos((string) $response->headers->get('Content-Type'), 'text/html')
  86.             || false !== stripos((string) $response->headers->get('Content-Disposition'), 'attachment;')
  87.         ) {
  88.             return;
  89.         }
  91.         $this->injectToolbar($response, $request);
  92.     }
  94.     /**
  95.      * @throws TwigError
  96.      */
  97.     private function injectToolbar(Response $response, Request $request): void
  98.     {
  99.         $content = $response->getContent();
  100.         $pos = strripos($content, '</body>');
  102.         if (false === $pos) {
  103.             return;
  104.         }
  106.         $toolbar = $this->twig->render(
  107.             '@ContaoCore/Frontend/preview_toolbar_base_js.html.twig',
  108.             [
  109.                 'action' => $this->router->generate('contao_backend_switch'),
  110.                 'request' => $request,
  111.                 'preview_script' => $this->previewScript,
  112.             ]
  113.         );
  115.         $response->setContent(substr($content, 0, $pos)."\n".$toolbar."\n".substr($content, $pos));
  116.     }
  117. }