Differential D20980 Diff 49996 src/events/PhutilEventEngine.php

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src/events/PhutilEventEngine.php

This file was added.

				<?php

				final class PhutilEventEngine extends Phobject {

				private static $instance;

				private $listeners = array();

				private function __construct() {
				// <empty>
				}

				public static function getInstance() {
				if (!self::$instance) {
				self::$instance = new PhutilEventEngine();
				}
				return self::$instance;
				}

				public function addListener(PhutilEventListener $listener, $type) {
				$this->listeners[$type][] = $listener;
				return $this;
				}

				/**
				* Get all the objects currently listening to any event.
				*/
				public function getAllListeners() {
				$listeners = array_mergev($this->listeners);
				$listeners = mpull($listeners, null, 'getListenerID');
				return $listeners;
				}

				public static function dispatchEvent(PhutilEvent $event) {
				$instance = self::getInstance();

				$listeners = idx($instance->listeners, $event->getType(), array());
				$global_listeners = idx(
				$instance->listeners,
				PhutilEventType::TYPE_ALL,
				array());

				// Merge and deduplicate listeners (we want to send the event to each
				// listener only once, even if it satisfies multiple criteria for the
				// event).
				$listeners = array_merge($listeners, $global_listeners);
				$listeners = mpull($listeners, null, 'getListenerID');

				$profiler = PhutilServiceProfiler::getInstance();
				$profiler_id = $profiler->beginServiceCall(
				array(
				'type' => 'event',
				'kind' => $event->getType(),
				'count' => count($listeners),
				));

				$caught = null;
				try {
				foreach ($listeners as $listener) {
				if ($event->isStopped()) {
				// Do this first so if someone tries to dispatch a stopped event it
				// doesn't go anywhere. Silly but less surprising.
				break;
				}
				$listener->handleEvent($event);
				}
				} catch (Exception $ex) {
				$profiler->endServiceCall($profiler_id, array());
				throw $ex;
				}

				$profiler->endServiceCall($profiler_id, array());
				}

				}