ProfilerListener.php

<?php


/*
 * This file is part of the Symfony package.
 *
 * (c) Fabien Potencier <fabien@symfony.com>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */
namespace Symfony\Component\HttpKernel\EventListener;

use Symfony\Component\EventDispatcher\EventSubscriberInterface;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\RequestMatcherInterface;
use Symfony\Component\HttpFoundation\RequestStack;
use Symfony\Component\HttpFoundation\Session\Session;
use Symfony\Component\HttpKernel\Event\ExceptionEvent;
use Symfony\Component\HttpKernel\Event\ResponseEvent;
use Symfony\Component\HttpKernel\Event\TerminateEvent;
use Symfony\Component\HttpKernel\KernelEvents;
use Symfony\Component\HttpKernel\Profiler\Profile;
use Symfony\Component\HttpKernel\Profiler\Profiler;

/**
 * ProfilerListener collects data for the current request by listening to the kernel events.
 *
 * @author Fabien Potencier <fabien@symfony.com>
 *
 * @final
 */
class ProfilerListener implements EventSubscriberInterface {
    private ?\Throwable $exception = null;
    
    /** @var \SplObjectStorage<Request, Profile> */
    private \SplObjectStorage $profiles;
    
    /** @var \SplObjectStorage<Request, Request|null> */
    private \SplObjectStorage $parents;
    
    /**
     * @param bool $onlyException    True if the profiler only collects data when an exception occurs, false otherwise
     * @param bool $onlyMainRequests True if the profiler only collects data when the request is the main request, false otherwise
     */
    public function __construct(Profiler $profiler, RequestStack $requestStack, ?RequestMatcherInterface $matcher = null, bool $onlyException = false, bool $onlyMainRequests = false, ?string $collectParameter = null) {
        $this->profiles = new \SplObjectStorage();
        $this->parents = new \SplObjectStorage();
    }
    
    /**
     * Handles the onKernelException event.
     */
    public function onKernelException(ExceptionEvent $event) : void {
        if ($this->onlyMainRequests && !$event->isMainRequest()) {
            return;
        }
        $this->exception = $event->getThrowable();
    }
    
    /**
     * Handles the onKernelResponse event.
     */
    public function onKernelResponse(ResponseEvent $event) : void {
        if ($this->onlyMainRequests && !$event->isMainRequest()) {
            return;
        }
        if ($this->onlyException && null === $this->exception) {
            return;
        }
        $request = $event->getRequest();
        if (null !== $this->collectParameter && null !== ($collectParameterValue = $request->get($this->collectParameter))) {
            true === $collectParameterValue || filter_var($collectParameterValue, \FILTER_VALIDATE_BOOL) ? $this->profiler
                ->enable() : $this->profiler
                ->disable();
        }
        $exception = $this->exception;
        $this->exception = null;
        if (null !== $this->matcher && !$this->matcher
            ->matches($request)) {
            return;
        }
        $session = !$request->attributes
            ->getBoolean('_stateless') && $request->hasPreviousSession() ? $request->getSession() : null;
        if ($session instanceof Session) {
            $usageIndexValue = $usageIndexReference =& $session->getUsageIndex();
            $usageIndexReference = \PHP_INT_MIN;
        }
        try {
            if (!($profile = $this->profiler
                ->collect($request, $event->getResponse(), $exception))) {
                return;
            }
        } finally {
            if ($session instanceof Session) {
                $usageIndexReference = $usageIndexValue;
            }
        }
        $this->profiles[$request] = $profile;
        $this->parents[$request] = $this->requestStack
            ->getParentRequest();
    }
    public function onKernelTerminate(TerminateEvent $event) : void {
        // attach children to parents
        foreach ($this->profiles as $request) {
            if (null !== ($parentRequest = $this->parents[$request])) {
                if (isset($this->profiles[$parentRequest])) {
                    $this->profiles[$parentRequest]
                        ->addChild($this->profiles[$request]);
                }
            }
        }
        // save profiles
        foreach ($this->profiles as $request) {
            $this->profiler
                ->saveProfile($this->profiles[$request]);
        }
        $this->profiles = new \SplObjectStorage();
        $this->parents = new \SplObjectStorage();
    }
    public static function getSubscribedEvents() : array {
        return [
            KernelEvents::RESPONSE => [
                'onKernelResponse',
                -100,
            ],
            KernelEvents::EXCEPTION => [
                'onKernelException',
                0,
            ],
            KernelEvents::TERMINATE => [
                'onKernelTerminate',
                -1024,
            ],
        ];
    }

}