class TraceableEventDispatcher in Zircon Profile 8

Collects some data about event listeners.

This event dispatcher delegates the dispatching to another one.

@author Fabien Potencier <[e-mail]>

Hierarchy

• class \Symfony\Component\EventDispatcher\Debug\TraceableEventDispatcher implements TraceableEventDispatcherInterface

2 files declare their use of TraceableEventDispatcher

TraceableEventDispatcher.php in vendor/symfony/http-kernel/Debug/TraceableEventDispatcher.php

TraceableEventDispatcherTest.php in vendor/symfony/event-dispatcher/Tests/Debug/TraceableEventDispatcherTest.php

File

vendor/symfony/event-dispatcher/Debug/TraceableEventDispatcher.php, line 27

Namespace

Symfony\Component\EventDispatcher\Debug

class TraceableEventDispatcher implements TraceableEventDispatcherInterface {
  protected $logger;
  protected $stopwatch;
  private $called;
  private $dispatcher;
  private $wrappedListeners;

  /**
   * Constructor.
   *
   * @param EventDispatcherInterface $dispatcher An EventDispatcherInterface instance
   * @param Stopwatch                $stopwatch  A Stopwatch instance
   * @param LoggerInterface          $logger     A LoggerInterface instance
   */
  public function __construct(EventDispatcherInterface $dispatcher, Stopwatch $stopwatch, LoggerInterface $logger = null) {
    $this->dispatcher = $dispatcher;
    $this->stopwatch = $stopwatch;
    $this->logger = $logger;
    $this->called = array();
    $this->wrappedListeners = array();
  }

  /**
   * {@inheritdoc}
   */
  public function addListener($eventName, $listener, $priority = 0) {
    $this->dispatcher
      ->addListener($eventName, $listener, $priority);
  }

  /**
   * {@inheritdoc}
   */
  public function addSubscriber(EventSubscriberInterface $subscriber) {
    $this->dispatcher
      ->addSubscriber($subscriber);
  }

  /**
   * {@inheritdoc}
   */
  public function removeListener($eventName, $listener) {
    if (isset($this->wrappedListeners[$eventName])) {
      foreach ($this->wrappedListeners[$eventName] as $index => $wrappedListener) {
        if ($wrappedListener
          ->getWrappedListener() === $listener) {
          $listener = $wrappedListener;
          unset($this->wrappedListeners[$eventName][$index]);
          break;
        }
      }
    }
    return $this->dispatcher
      ->removeListener($eventName, $listener);
  }

  /**
   * {@inheritdoc}
   */
  public function removeSubscriber(EventSubscriberInterface $subscriber) {
    return $this->dispatcher
      ->removeSubscriber($subscriber);
  }

  /**
   * {@inheritdoc}
   */
  public function getListeners($eventName = null) {
    return $this->dispatcher
      ->getListeners($eventName);
  }

  /**
   * {@inheritdoc}
   */
  public function hasListeners($eventName = null) {
    return $this->dispatcher
      ->hasListeners($eventName);
  }

  /**
   * {@inheritdoc}
   */
  public function dispatch($eventName, Event $event = null) {
    if (null === $event) {
      $event = new Event();
    }
    $this
      ->preProcess($eventName);
    $this
      ->preDispatch($eventName, $event);
    $e = $this->stopwatch
      ->start($eventName, 'section');
    $this->dispatcher
      ->dispatch($eventName, $event);
    if ($e
      ->isStarted()) {
      $e
        ->stop();
    }
    $this
      ->postDispatch($eventName, $event);
    $this
      ->postProcess($eventName);
    return $event;
  }

  /**
   * {@inheritdoc}
   */
  public function getCalledListeners() {
    $called = array();
    foreach ($this->called as $eventName => $listeners) {
      foreach ($listeners as $listener) {
        $info = $this
          ->getListenerInfo($listener
          ->getWrappedListener(), $eventName);
        $called[$eventName . '.' . $info['pretty']] = $info;
      }
    }
    return $called;
  }

  /**
   * {@inheritdoc}
   */
  public function getNotCalledListeners() {
    try {
      $allListeners = $this
        ->getListeners();
    } catch (\Exception $e) {
      if (null !== $this->logger) {
        $this->logger
          ->info('An exception was thrown while getting the uncalled listeners.', array(
          'exception' => $e,
        ));
      }

      // unable to retrieve the uncalled listeners
      return array();
    }
    $notCalled = array();
    foreach ($allListeners as $eventName => $listeners) {
      foreach ($listeners as $listener) {
        $called = false;
        if (isset($this->called[$eventName])) {
          foreach ($this->called[$eventName] as $l) {
            if ($l
              ->getWrappedListener() === $listener) {
              $called = true;
              break;
            }
          }
        }
        if (!$called) {
          $info = $this
            ->getListenerInfo($listener, $eventName);
          $notCalled[$eventName . '.' . $info['pretty']] = $info;
        }
      }
    }
    return $notCalled;
  }

  /**
   * Proxies all method calls to the original event dispatcher.
   *
   * @param string $method    The method name
   * @param array  $arguments The method arguments
   *
   * @return mixed
   */
  public function __call($method, $arguments) {
    return call_user_func_array(array(
      $this->dispatcher,
      $method,
    ), $arguments);
  }

  /**
   * Called before dispatching the event.
   *
   * @param string $eventName The event name
   * @param Event  $event     The event
   */
  protected function preDispatch($eventName, Event $event) {
  }

  /**
   * Called after dispatching the event.
   *
   * @param string $eventName The event name
   * @param Event  $event     The event
   */
  protected function postDispatch($eventName, Event $event) {
  }
  private function preProcess($eventName) {
    foreach ($this->dispatcher
      ->getListeners($eventName) as $listener) {
      $this->dispatcher
        ->removeListener($eventName, $listener);
      $info = $this
        ->getListenerInfo($listener, $eventName);
      $name = isset($info['class']) ? $info['class'] : $info['type'];
      $wrappedListener = new WrappedListener($listener, $name, $this->stopwatch, $this);
      $this->wrappedListeners[$eventName][] = $wrappedListener;
      $this->dispatcher
        ->addListener($eventName, $wrappedListener);
    }
  }
  private function postProcess($eventName) {
    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
      $this->dispatcher
        ->removeListener($eventName, $listener);
      $this->dispatcher
        ->addListener($eventName, $listener
        ->getWrappedListener());
      $info = $this
        ->getListenerInfo($listener
        ->getWrappedListener(), $eventName);
      if ($listener
        ->wasCalled()) {
        if (null !== $this->logger) {
          $this->logger
            ->debug(sprintf('Notified event "%s" to listener "%s".', $eventName, $info['pretty']));
        }
        if (!isset($this->called[$eventName])) {
          $this->called[$eventName] = new \SplObjectStorage();
        }
        $this->called[$eventName]
          ->attach($listener);
      }
      if (null !== $this->logger && $skipped) {
        $this->logger
          ->debug(sprintf('Listener "%s" was not called for event "%s".', $info['pretty'], $eventName));
      }
      if ($listener
        ->stoppedPropagation()) {
        if (null !== $this->logger) {
          $this->logger
            ->debug(sprintf('Listener "%s" stopped propagation of the event "%s".', $info['pretty'], $eventName));
        }
        $skipped = true;
      }
    }
  }

  /**
   * Returns information about the listener.
   *
   * @param object $listener  The listener
   * @param string $eventName The event name
   *
   * @return array Information about the listener
   */
  private function getListenerInfo($listener, $eventName) {
    $info = array(
      'event' => $eventName,
    );
    if ($listener instanceof \Closure) {
      $info += array(
        'type' => 'Closure',
        'pretty' => 'closure',
      );
    }
    elseif (is_string($listener)) {
      try {
        $r = new \ReflectionFunction($listener);
        $file = $r
          ->getFileName();
        $line = $r
          ->getStartLine();
      } catch (\ReflectionException $e) {
        $file = null;
        $line = null;
      }
      $info += array(
        'type' => 'Function',
        'function' => $listener,
        'file' => $file,
        'line' => $line,
        'pretty' => $listener,
      );
    }
    elseif (is_array($listener) || is_object($listener) && is_callable($listener)) {
      if (!is_array($listener)) {
        $listener = array(
          $listener,
          '__invoke',
        );
      }
      $class = is_object($listener[0]) ? get_class($listener[0]) : $listener[0];
      try {
        $r = new \ReflectionMethod($class, $listener[1]);
        $file = $r
          ->getFileName();
        $line = $r
          ->getStartLine();
      } catch (\ReflectionException $e) {
        $file = null;
        $line = null;
      }
      $info += array(
        'type' => 'Method',
        'class' => $class,
        'method' => $listener[1],
        'file' => $file,
        'line' => $line,
        'pretty' => $class . '::' . $listener[1],
      );
    }
    return $info;
  }

}

Members

Name	Modifiers	Type	Description	Overrides
TraceableEventDispatcher::$called	private	property
TraceableEventDispatcher::$dispatcher	private	property
TraceableEventDispatcher::$logger	protected	property
TraceableEventDispatcher::$stopwatch	protected	property
TraceableEventDispatcher::$wrappedListeners	private	property
TraceableEventDispatcher::addListener	public	function	Adds an event listener that listens on the specified events. Overrides EventDispatcherInterface::addListener
TraceableEventDispatcher::addSubscriber	public	function	Adds an event subscriber. Overrides EventDispatcherInterface::addSubscriber
TraceableEventDispatcher::dispatch	public	function	Dispatches an event to all registered listeners. Overrides EventDispatcherInterface::dispatch
TraceableEventDispatcher::getCalledListeners	public	function	Gets the called listeners. Overrides TraceableEventDispatcherInterface::getCalledListeners
TraceableEventDispatcher::getListenerInfo	private	function	Returns information about the listener.
TraceableEventDispatcher::getListeners	public	function	Gets the listeners of a specific event or all listeners sorted by descending priority. Overrides EventDispatcherInterface::getListeners
TraceableEventDispatcher::getNotCalledListeners	public	function	Gets the not called listeners. Overrides TraceableEventDispatcherInterface::getNotCalledListeners
TraceableEventDispatcher::hasListeners	public	function	Checks whether an event has any registered listeners. Overrides EventDispatcherInterface::hasListeners
TraceableEventDispatcher::postDispatch	protected	function	Called after dispatching the event.	1
TraceableEventDispatcher::postProcess	private	function
TraceableEventDispatcher::preDispatch	protected	function	Called before dispatching the event.	1
TraceableEventDispatcher::preProcess	private	function
TraceableEventDispatcher::removeListener	public	function	Removes an event listener from the specified events. Overrides EventDispatcherInterface::removeListener
TraceableEventDispatcher::removeSubscriber	public	function	Removes an event subscriber. Overrides EventDispatcherInterface::removeSubscriber
TraceableEventDispatcher::__call	public	function	Proxies all method calls to the original event dispatcher.
TraceableEventDispatcher::__construct	public	function	Constructor.