Part-DB.Part-DB-server/src/EventSubscriber/SymfonyDebugToolbarSubscriber.php

<?php
/**
 *
 * part-db version 0.1
 * Copyright (C) 2005 Christoph Lechner
 * http://www.cl-projects.de/
 *
 * part-db version 0.2+
 * Copyright (C) 2009 K. Jacobs and others (see authors.php)
 * http://code.google.com/p/part-db/
 *
 * Part-DB Version 0.4+
 * Copyright (C) 2016 - 2019 Jan Böhmer
 * https://github.com/jbtronics
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
 *
 */

namespace App\EventSubscriber;

use Symfony\Component\DependencyInjection\ContainerInterface;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;
use Symfony\Component\EventDispatcher\Tests\Debug\EventSubscriber;
use Symfony\Component\HttpKernel\Event\FilterResponseEvent;

class SymfonyDebugToolbarSubscriber implements EventSubscriberInterface
{

    protected $kernel;

    public function __construct(ContainerInterface $kernel)
    {
        $this->kernel = $kernel;
    }

    /**
     * Returns an array of event names this subscriber wants to listen to.
     *
     * The array keys are event names and the value can be:
     *
     *  * The method name to call (priority defaults to 0)
     *  * An array composed of the method name to call and the priority
     *  * An array of arrays composed of the method names to call and respective
     *    priorities, or 0 if unset
     *
     * For instance:
     *
     *  * ['eventName' => 'methodName']
     *  * ['eventName' => ['methodName', $priority]]
     *  * ['eventName' => [['methodName1', $priority], ['methodName2']]]
     *
     * @return array The event names to listen to
     */
    public static function getSubscribedEvents()
    {
        return ['kernel.response' => 'onKernelResponse'];
    }


    public function onKernelResponse(FilterResponseEvent $event)
    {
        if (!$this->kernel->getParameter('kernel.debug')) {
            return;
        }

        $response = $event->getResponse();
        $response->headers->set('Symfony-Debug-Toolbar-Replace', 1);
    }

}