<?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\EventDispatcher\Debug;
use Psr\EventDispatcher\StoppableEventInterface;
use Psr\Log\LoggerInterface;
use Symfony\Component\EventDispatcher\EventDispatcher;
use Symfony\Component\EventDispatcher\EventDispatcherInterface;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\RequestStack;
use Symfony\Component\Stopwatch\Stopwatch;
use Symfony\Contracts\Service\ResetInterface;
/**
* Collects some data about event listeners.
*
* This event dispatcher delegates the dispatching to another one.
*
* @author Fabien Potencier <fabien@symfony.com>
*/
class TraceableEventDispatcher implements EventDispatcherInterface, ResetInterface
{
protected $logger;
protected $stopwatch;
/**
* @var \SplObjectStorage<WrappedListener, array{string, string}>|null
*/
private ?\SplObjectStorage $callStack = null;
private EventDispatcherInterface $dispatcher;
private array $wrappedListeners = [];
private array $orphanedEvents = [];
private ?RequestStack $requestStack;
private string $currentRequestHash = '';
public function __construct(EventDispatcherInterface $dispatcher, Stopwatch $stopwatch, LoggerInterface $logger = null, RequestStack $requestStack = null)
{
$this->dispatcher = $dispatcher;
$this->stopwatch = $stopwatch;
$this->logger = $logger;
$this->requestStack = $requestStack;
}
public function addListener(string $eventName, callable|array $listener, int $priority = 0)
{
$this->dispatcher->addListener($eventName, $listener, $priority);
}
public function addSubscriber(EventSubscriberInterface $subscriber)
{
$this->dispatcher->addSubscriber($subscriber);
}
public function removeListener(string $eventName, callable|array $listener)
{
if (isset($this->wrappedListeners[$eventName])) {
foreach ($this->wrappedListeners[$eventName] as $index => $wrappedListener) {
if ($wrappedListener->getWrappedListener() === $listener || ($listener instanceof \Closure && $wrappedListener->getWrappedListener() == $listener)) {
$listener = $wrappedListener;
unset($this->wrappedListeners[$eventName][$index]);
break;
}
}
}
return $this->dispatcher->removeListener($eventName, $listener);
}
public function removeSubscriber(EventSubscriberInterface $subscriber)
{
return $this->dispatcher->removeSubscriber($subscriber);
}
public function getListeners(string $eventName = null): array
{
return $this->dispatcher->getListeners($eventName);
}
public function getListenerPriority(string $eventName, callable|array $listener): ?int
{
// we might have wrapped listeners for the event (if called while dispatching)
// in that case get the priority by wrapper
if (isset($this->wrappedListeners[$eventName])) {
foreach ($this->wrappedListeners[$eventName] as $wrappedListener) {
if ($wrappedListener->getWrappedListener() === $listener || ($listener instanceof \Closure && $wrappedListener->getWrappedListener() == $listener)) {
return $this->dispatcher->getListenerPriority($eventName, $wrappedListener);
}
}
}
return $this->dispatcher->getListenerPriority($eventName, $listener);
}
public function hasListeners(string $eventName = null): bool
{
return $this->dispatcher->hasListeners($eventName);
}
public function dispatch(object $event, string $eventName = null): object
{
$eventName ??= $event::class;
$this->callStack ??= new \SplObjectStorage();
$currentRequestHash = $this->currentRequestHash = $this->requestStack && ($request = $this->requestStack->getCurrentRequest()) ? spl_object_hash($request) : '';
if (null !== $this->logger && $event instanceof StoppableEventInterface && $event->isPropagationStopped()) {
$this->logger->debug(sprintf('The "%s" event is already stopped. No listeners have been called.', $eventName));
}
$this->preProcess($eventName);
try {
$this->beforeDispatch($eventName, $event);
try {
$e = $this->stopwatch->start($eventName, 'section');
try {
$this->dispatcher->dispatch($event, $eventName);
} finally {
if ($e->isStarted()) {
$e->stop();
}
}
} finally {
$this->afterDispatch($eventName, $event);
}
} finally {
$this->currentRequestHash = $currentRequestHash;
$this->postProcess($eventName);
}
return $event;
}
public function getCalledListeners(Request $request = null): array
{
if (null === $this->callStack) {
return [];
}
$hash = $request ? spl_object_hash($request) : null;
$called = [];
foreach ($this->callStack as $listener) {
[$eventName, $requestHash] = $this->callStack->getInfo();
if (null === $hash || $hash === $requestHash) {
$called[] = $listener->getInfo($eventName);
}
}
return $called;
}
public function getNotCalledListeners(Request $request = null): array
{
try {
$allListeners = $this->dispatcher instanceof EventDispatcher ? $this->getListenersWithPriority() : $this->getListenersWithoutPriority();
} catch (\Exception $e) {
$this->logger?->info('An exception was thrown while getting the uncalled listeners.', ['exception' => $e]);
// unable to retrieve the uncalled listeners
return [];
}
$hash = $request ? spl_object_hash($request) : null;
$calledListeners = [];
if (null !== $this->callStack) {
foreach ($this->callStack as $calledListener) {
[, $requestHash] = $this->callStack->getInfo();
if (null === $hash || $hash === $requestHash) {
$calledListeners[] = $calledListener->getWrappedListener();
}
}
}
$notCalled = [];
foreach ($allListeners as $eventName => $listeners) {
foreach ($listeners as [$listener, $priority]) {
if (!\in_array($listener, $calledListeners, true)) {
if (!$listener instanceof WrappedListener) {
$listener = new WrappedListener($listener, null, $this->stopwatch, $this, $priority);
}
$notCalled[] = $listener->getInfo($eventName);
}
}
}
uasort($notCalled, $this->sortNotCalledListeners(...));
return $notCalled;
}
public function getOrphanedEvents(Request $request = null): array
{
if ($request) {
return $this->orphanedEvents[spl_object_hash($request)] ?? [];
}
if (!$this->orphanedEvents) {
return [];
}
return array_merge(...array_values($this->orphanedEvents));
}
public function reset()
{
$this->callStack = null;
$this->orphanedEvents = [];
$this->currentRequestHash = '';
}
/**
* Proxies all method calls to the original event dispatcher.
*
* @param string $method The method name
* @param array $arguments The method arguments
*/
public function __call(string $method, array $arguments): mixed
{
return $this->dispatcher->{$method}(...$arguments);
}
/**
* Called before dispatching the event.
*/
protected function beforeDispatch(string $eventName, object $event)
{
}
/**
* Called after dispatching the event.
*/
protected function afterDispatch(string $eventName, object $event)
{
}
private function preProcess(string $eventName): void
{
if (!$this->dispatcher->hasListeners($eventName)) {
$this->orphanedEvents[$this->currentRequestHash][] = $eventName;
return;
}
foreach ($this->dispatcher->getListeners($eventName) as $listener) {
$priority = $this->getListenerPriority($eventName, $listener);
$wrappedListener = new WrappedListener($listener instanceof WrappedListener ? $listener->getWrappedListener() : $listener, null, $this->stopwatch, $this);
$this->wrappedListeners[$eventName][] = $wrappedListener;
$this->dispatcher->removeListener($eventName, $listener);
$this->dispatcher->addListener($eventName, $wrappedListener, $priority);
$this->callStack->attach($wrappedListener, [$eventName, $this->currentRequestHash]);
}
}
private function postProcess(string $eventName): void
{
unset($this->wrappedListeners[$eventName]);
$skipped = false;
foreach ($this->dispatcher->getListeners($eventName) as $listener) {
if (!$listener instanceof WrappedListener) { // #12845: a new listener was added during dispatch.
continue;
}
// Unwrap listener
$priority = $this->getListenerPriority($eventName, $listener);
$this->dispatcher->removeListener($eventName, $listener);
$this->dispatcher->addListener($eventName, $listener->getWrappedListener(), $priority);
if (null !== $this->logger) {
$context = ['event' => $eventName, 'listener' => $listener->getPretty()];
}
if ($listener->wasCalled()) {
$this->logger?->debug('Notified event "{event}" to listener "{listener}".', $context);
} else {
$this->callStack->detach($listener);
}
if (null !== $this->logger && $skipped) {
$this->logger->debug('Listener "{listener}" was not called for event "{event}".', $context);
}
if ($listener->stoppedPropagation()) {
$this->logger?->debug('Listener "{listener}" stopped propagation of the event "{event}".', $context);
$skipped = true;
}
}
}
private function sortNotCalledListeners(array $a, array $b): int
{
if (0 !== $cmp = strcmp($a['event'], $b['event'])) {
return $cmp;
}
if (\is_int($a['priority']) && !\is_int($b['priority'])) {
return 1;
}
if (!\is_int($a['priority']) && \is_int($b['priority'])) {
return -1;
}
if ($a['priority'] === $b['priority']) {
return 0;
}
if ($a['priority'] > $b['priority']) {
return -1;
}
return 1;
}
private function getListenersWithPriority(): array
{
$result = [];
$allListeners = new \ReflectionProperty(EventDispatcher::class, 'listeners');
$allListeners->setAccessible(true);
foreach ($allListeners->getValue($this->dispatcher) as $eventName => $listenersByPriority) {
foreach ($listenersByPriority as $priority => $listeners) {
foreach ($listeners as $listener) {
$result[$eventName][] = [$listener, $priority];
}
}
}
return $result;
}
private function getListenersWithoutPriority(): array
{
$result = [];
foreach ($this->getListeners() as $eventName => $listeners) {
foreach ($listeners as $listener) {
$result[$eventName][] = [$listener, null];
}
}
return $result;
}
}