Chris@0: <?php
Chris@0: 
Chris@0: namespace Drupal\Core\EventSubscriber;
Chris@0: 
Chris@0: use Drupal\Component\Utility\Html;
Chris@0: use Drupal\Core\Ajax\AjaxResponse;
Chris@0: use Drupal\Core\Render\AttachmentsResponseProcessorInterface;
Chris@0: use Symfony\Component\EventDispatcher\EventSubscriberInterface;
Chris@0: use Symfony\Component\HttpKernel\Event\FilterResponseEvent;
Chris@0: use Symfony\Component\HttpKernel\Event\GetResponseEvent;
Chris@0: use Symfony\Component\HttpKernel\KernelEvents;
Chris@0: 
Chris@0: /**
Chris@0:  * Response subscriber to handle AJAX responses.
Chris@0:  */
Chris@0: class AjaxResponseSubscriber implements EventSubscriberInterface {
Chris@0: 
Chris@0:   /**
Chris@0:    * The AJAX response attachments processor service.
Chris@0:    *
Chris@0:    * @var \Drupal\Core\Render\AttachmentsResponseProcessorInterface
Chris@0:    */
Chris@0:   protected $ajaxResponseAttachmentsProcessor;
Chris@0: 
Chris@0:   /**
Chris@0:    * Constructs an AjaxResponseSubscriber object.
Chris@0:    *
Chris@0:    * @param \Drupal\Core\Render\AttachmentsResponseProcessorInterface $ajax_response_attachments_processor
Chris@0:    *   The AJAX response attachments processor service.
Chris@0:    */
Chris@0:   public function __construct(AttachmentsResponseProcessorInterface $ajax_response_attachments_processor) {
Chris@0:     $this->ajaxResponseAttachmentsProcessor = $ajax_response_attachments_processor;
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Request parameter to indicate that a request is a Drupal Ajax request.
Chris@0:    */
Chris@0:   const AJAX_REQUEST_PARAMETER = '_drupal_ajax';
Chris@0: 
Chris@0:   /**
Chris@0:    * Sets the AJAX parameter from the current request.
Chris@0:    *
Chris@0:    * @param \Symfony\Component\HttpKernel\Event\GetResponseEvent $event
Chris@0:    *   The response event, which contains the current request.
Chris@0:    */
Chris@0:   public function onRequest(GetResponseEvent $event) {
Chris@0:     // Pass to the Html class that the current request is an Ajax request.
Chris@0:     if ($event->getRequest()->request->get(static::AJAX_REQUEST_PARAMETER)) {
Chris@0:       Html::setIsAjax(TRUE);
Chris@0:     }
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Renders the ajax commands right before preparing the result.
Chris@0:    *
Chris@0:    * @param \Symfony\Component\HttpKernel\Event\FilterResponseEvent $event
Chris@0:    *   The response event, which contains the possible AjaxResponse object.
Chris@0:    */
Chris@0:   public function onResponse(FilterResponseEvent $event) {
Chris@0:     $response = $event->getResponse();
Chris@0:     if ($response instanceof AjaxResponse) {
Chris@0:       $this->ajaxResponseAttachmentsProcessor->processAttachments($response);
Chris@0: 
Chris@0:       // IE 9 does not support XHR 2 (http://caniuse.com/#feat=xhr2), so
Chris@0:       // for that browser, jquery.form submits requests containing a file upload
Chris@0:       // via an IFRAME rather than via XHR. Since the response is being sent to
Chris@0:       // an IFRAME, it must be formatted as HTML. Specifically:
Chris@0:       // - It must use the text/html content type or else the browser will
Chris@0:       //   present a download prompt. Note: This applies to both file uploads
Chris@0:       //   as well as any ajax request in a form with a file upload form.
Chris@0:       // - It must place the JSON data into a textarea to prevent browser
Chris@0:       //   extensions such as Linkification and Skype's Browser Highlighter
Chris@0:       //   from applying HTML transformations such as URL or phone number to
Chris@0:       //   link conversions on the data values.
Chris@0:       //
Chris@0:       // Since this affects the format of the output, it could be argued that
Chris@0:       // this should be implemented as a separate Accept MIME type. However,
Chris@0:       // that would require separate variants for each type of AJAX request
Chris@0:       // (e.g., drupal-ajax, drupal-dialog, drupal-modal), so for expediency,
Chris@0:       // this browser workaround is implemented via a GET or POST parameter.
Chris@0:       //
Chris@0:       // @see http://malsup.com/jquery/form/#file-upload
Chris@0:       // @see https://www.drupal.org/node/1009382
Chris@0:       // @see https://www.drupal.org/node/2339491
Chris@0:       // @see Drupal.ajax.prototype.beforeSend()
Chris@0:       $accept = $event->getRequest()->headers->get('accept');
Chris@0: 
Chris@0:       if (strpos($accept, 'text/html') !== FALSE) {
Chris@0:         $response->headers->set('Content-Type', 'text/html; charset=utf-8');
Chris@0: 
Chris@0:         // Browser IFRAMEs expect HTML. Browser extensions, such as Linkification
Chris@0:         // and Skype's Browser Highlighter, convert URLs, phone numbers, etc.
Chris@0:         // into links. This corrupts the JSON response. Protect the integrity of
Chris@0:         // the JSON data by making it the value of a textarea.
Chris@0:         // @see http://malsup.com/jquery/form/#file-upload
Chris@0:         // @see https://www.drupal.org/node/1009382
Chris@0:         $response->setContent('<textarea>' . $response->getContent() . '</textarea>');
Chris@0:       }
Chris@0: 
Chris@0:       // User-uploaded files cannot set any response headers, so a custom header
Chris@0:       // is used to indicate to ajax.js that this response is safe. Note that
Chris@0:       // most Ajax requests bound using the Form API will be protected by having
Chris@0:       // the URL flagged as trusted in Drupal.settings, so this header is used
Chris@0:       // only for things like custom markup that gets Ajax behaviors attached.
Chris@0:       $response->headers->set('X-Drupal-Ajax-Token', 1);
Chris@0:     }
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public static function getSubscribedEvents() {
Chris@0:     $events[KernelEvents::RESPONSE][] = ['onResponse', -100];
Chris@0:     $events[KernelEvents::REQUEST][] = ['onRequest', 50];
Chris@0: 
Chris@0:     return $events;
Chris@0:   }
Chris@0: 
Chris@0: }