Same filename in other branches
  1. 6.0.x src/EventSubscriber/ResponseSubscriber.php
  2. 8.x-3.x src/EventSubscriber/ResponseSubscriber.php
  3. 8.x-4.x src/EventSubscriber/ResponseSubscriber.php

Namespace

Drupal\advagg\EventSubscriber

File

src/EventSubscriber/ResponseSubscriber.php

View source 
<?php

namespace Drupal\advagg\EventSubscriber;

use Drupal\Core\Config\ConfigFactoryInterface;
use Drupal\Core\Render\HtmlResponse;
use Symfony\Component\HttpKernel\Event\ResponseEvent;
use Symfony\Component\HttpKernel\KernelEvents;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;

/**
 * Respond to event processes.
 */
class ResponseSubscriber implements EventSubscriberInterface {
    
    /**
     * A config object for the advagg configuration.
     *
     * @var \Drupal\Core\Config\Config
     */
    protected $config;
    
    /**
     * Constructs the Subscriber object.
     *
     * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
     *   A config factory for retrieving required config objects.
     */
    public function __construct(ConfigFactoryInterface $config_factory) {
        $this->config = $config_factory->get('advagg.settings');
    }
    
    /**
     * {@inheritdoc}
     */
    public static function getSubscribedEvents() {
        return [
            KernelEvents::RESPONSE => [
                [
                    'processResponse',
                    -9999,
                ],
                [
                    'forceAbsolutePaths',
                    0,
                ],
            ],
        ];
    }
    
    /**
     * Passes HtmlResponse responses on to other functions if enabled.
     *
     * @param \Symfony\Component\HttpKernel\Event\ResponseEvent $event
     *   The event to process.
     */
    public function processResponse(ResponseEvent $event) {
        // Only subscribe to the event if DNS prefetching is enabled.
        if ($this->config
            ->get('dns_prefetch')) {
            $response = $event->getResponse();
            // Ensure that it is an html response.
            if (stripos($response->headers
                ->get('Content-Type'), 'text/html') === FALSE) {
                return;
            }
            global $_advagg_prefetch;
            if (empty($_advagg_prefetch)) {
                return;
            }
            $_advagg_prefetch = array_unique($_advagg_prefetch);
            $domains = '<head>';
            foreach ($_advagg_prefetch as $domain) {
                $domains .= "<link rel='dns-prefetch' href='{$domain}'>";
            }
            $response->setContent(str_replace('<head>', $domains, $response->getContent()));
        }
    }
    
    /**
     * Force absolute paths.
     *
     * @param \Symfony\Component\HttpKernel\Event\ResponseEvent $event
     *   The response event object.
     */
    public function forceAbsolutePaths(ResponseEvent $event) {
        // Skip if not enabled.
        if (!$this->config
            ->get('path.convert.absolute')) {
            return;
        }
        $response = $event->getResponse();
        // Only process Html Responses.
        if (!$response instanceof HtmlResponse) {
            return;
        }
        $content = $response->getContent();
        $pattern = '/(<script src="|url\\("|rel="stylesheet" href=")(\\/[a-zA-Z0-0].*")/';
        $response->setContent(preg_replace_callback($pattern, [
            $this,
            'forceAbsolutePathsCallback',
        ], $content));
    }
    
    /**
     * Callback to replace individual stylesheet links.
     *
     * @param array $matches
     *   Array from matches from preg_replace_callback.
     *
     * @return string
     *   Updated html string.
     */
    public function forceAbsolutePathsCallback(array $matches) {
        global $base_root;
        return "{$matches[1]}{$base_root}{$matches[2]}";
    }

}

Classes

Title Deprecated Summary
ResponseSubscriber Respond to event processes.