ContainerAwareEventDispatcher.php
Same filename in other branches
Namespace
Drupal\Component\EventDispatcherFile
-
core/
lib/ Drupal/ Component/ EventDispatcher/ ContainerAwareEventDispatcher.php
View source
<?php
namespace Drupal\Component\EventDispatcher;
use Symfony\Component\DependencyInjection\ContainerInterface;
use Symfony\Component\EventDispatcher\Event;
use Symfony\Component\EventDispatcher\EventDispatcherInterface;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;
use Symfony\Contracts\EventDispatcher\Event as ContractsEvent;
use Symfony\Contracts\EventDispatcher\EventDispatcherInterface as ContractsEventDispatcherInterface;
/**
* A performance optimized container aware event dispatcher.
*
* This version of the event dispatcher contains the following optimizations
* in comparison to the Symfony event dispatcher component:
*
* <dl>
* <dt>Faster instantiation of the event dispatcher service</dt>
* <dd>
* Instead of calling <code>addSubscriberService</code> once for each
* subscriber, a precompiled array of listener definitions is passed
* directly to the constructor. This is faster by roughly an order of
* magnitude. The listeners are collected and prepared using a compiler
* pass.
* </dd>
* <dt>Lazy instantiation of listeners</dt>
* <dd>
* Services are only retrieved from the container just before invocation.
* Especially when dispatching the KernelEvents::REQUEST event, this leads
* to a more timely invocation of the first listener. Overall dispatch
* runtime is not affected by this change though.
* </dd>
* </dl>
*/
class ContainerAwareEventDispatcher implements EventDispatcherInterface {
/**
* The service container.
*
* @var \Symfony\Component\DependencyInjection\ContainerInterface
*/
protected $container;
/**
* Listener definitions.
*
* A nested array of listener definitions keyed by event name and priority.
* A listener definition is an associative array with one of the following key
* value pairs:
* - callable: A callable listener
* - service: An array of the form [service id, method]
*
* A service entry will be resolved to a callable only just before its
* invocation.
*
* @var array
*/
protected $listeners;
/**
* Whether listeners need to be sorted prior to dispatch, keyed by event name.
*
* @var TRUE[]
*/
protected $unsorted;
/**
* Constructs a container aware event dispatcher.
*
* @param \Symfony\Component\DependencyInjection\ContainerInterface $container
* The service container.
* @param array $listeners
* A nested array of listener definitions keyed by event name and priority.
* The array is expected to be ordered by priority. A listener definition is
* an associative array with one of the following key value pairs:
* - callable: A callable listener
* - service: An array of the form [service id, method]
* A service entry will be resolved to a callable only just before its
* invocation.
*/
public function __construct(ContainerInterface $container, array $listeners = []) {
$this->container = $container;
$this->listeners = $listeners;
$this->unsorted = [];
}
/**
* {@inheritdoc}
*/
public function dispatch($event) {
$event_name = 1 < \func_num_args() ? func_get_arg(1) : NULL;
if (\is_object($event)) {
$class_name = get_class($event);
$event_name = $event_name ?? $class_name;
$deprecation_message = 'Symfony\\Component\\EventDispatcher\\Event is deprecated in drupal:9.1.0 and will be replaced by Symfony\\Contracts\\EventDispatcher\\Event in drupal:10.0.0. A new Drupal\\Component\\EventDispatcher\\Event class is available to bridge the two versions of the class. See https://www.drupal.org/node/3159012';
// Trigger a deprecation error if the deprecated Event class is used
// directly.
if ($class_name === 'Symfony\\Component\\EventDispatcher\\Event') {
@trigger_error($deprecation_message, E_USER_DEPRECATED);
}
elseif ($class_name !== 'Drupal\\Component\\EventDispatcher\\Event' && strpos($class_name, 'Drupal') !== FALSE) {
if (get_parent_class($event) === 'Symfony\\Component\\EventDispatcher\\Event') {
@trigger_error($deprecation_message, E_USER_DEPRECATED);
}
}
}
elseif (\is_string($event) && (NULL === $event_name || $event_name instanceof ContractsEvent || $event_name instanceof Event)) {
@trigger_error('Calling the Symfony\\Component\\EventDispatcher\\EventDispatcherInterface::dispatch() method with a string event name as the first argument is deprecated in drupal:9.1.0, an Event object will be required instead in drupal:10.0.0. See https://www.drupal.org/node/3154407', E_USER_DEPRECATED);
$swap = $event;
$event = $event_name ?? new Event();
$event_name = $swap;
}
else {
throw new \TypeError(sprintf('Argument 1 passed to "%s::dispatch()" must be an object, %s given.', ContractsEventDispatcherInterface::class, \gettype($event)));
}
if (isset($this->listeners[$event_name])) {
// Sort listeners if necessary.
if (isset($this->unsorted[$event_name])) {
krsort($this->listeners[$event_name]);
unset($this->unsorted[$event_name]);
}
// Invoke listeners and resolve callables if necessary.
foreach ($this->listeners[$event_name] as &$definitions) {
foreach ($definitions as &$definition) {
if (!isset($definition['callable'])) {
$definition['callable'] = [
$this->container
->get($definition['service'][0]),
$definition['service'][1],
];
}
if (is_array($definition['callable']) && isset($definition['callable'][0]) && $definition['callable'][0] instanceof \Closure) {
$definition['callable'][0] = $definition['callable'][0]();
}
call_user_func($definition['callable'], $event, $event_name, $this);
if ($event->isPropagationStopped()) {
return $event;
}
}
}
}
return $event;
}
/**
* {@inheritdoc}
*/
public function getListeners($event_name = NULL) : array {
$result = [];
if ($event_name === NULL) {
// If event name was omitted, collect all listeners of all events.
foreach (array_keys($this->listeners) as $event_name) {
$listeners = $this->getListeners($event_name);
if (!empty($listeners)) {
$result[$event_name] = $listeners;
}
}
}
elseif (isset($this->listeners[$event_name])) {
// Sort listeners if necessary.
if (isset($this->unsorted[$event_name])) {
krsort($this->listeners[$event_name]);
unset($this->unsorted[$event_name]);
}
// Collect listeners and resolve callables if necessary.
foreach ($this->listeners[$event_name] as &$definitions) {
foreach ($definitions as &$definition) {
if (!isset($definition['callable'])) {
$definition['callable'] = [
$this->container
->get($definition['service'][0]),
$definition['service'][1],
];
}
if (is_array($definition['callable']) && isset($definition['callable'][0]) && $definition['callable'][0] instanceof \Closure) {
$definition['callable'][0] = $definition['callable'][0]();
}
$result[] = $definition['callable'];
}
}
}
return $result;
}
/**
* {@inheritdoc}
*/
public function getListenerPriority($event_name, $listener) : ?int {
if (!isset($this->listeners[$event_name])) {
return NULL;
}
if (is_array($listener) && isset($listener[0]) && $listener[0] instanceof \Closure) {
$listener[0] = $listener[0]();
}
// Resolve service definitions if the listener has not been found so far.
foreach ($this->listeners[$event_name] as $priority => &$definitions) {
foreach ($definitions as &$definition) {
if (!isset($definition['callable'])) {
// Once the callable is retrieved we keep it for subsequent method
// invocations on this class.
$definition['callable'] = [
$this->container
->get($definition['service'][0]),
$definition['service'][1],
];
}
if (is_array($definition['callable']) && isset($definition['callable'][0]) && $definition['callable'][0] instanceof \Closure) {
$definition['callable'][0] = $definition['callable'][0]();
}
if ($definition['callable'] === $listener) {
return $priority;
}
}
}
return NULL;
}
/**
* {@inheritdoc}
*/
public function hasListeners($event_name = NULL) : bool {
if ($event_name !== NULL) {
return !empty($this->listeners[$event_name]);
}
foreach ($this->listeners as $event_listeners) {
if ($event_listeners) {
return TRUE;
}
}
return FALSE;
}
/**
* {@inheritdoc}
*/
public function addListener($event_name, $listener, $priority = 0) {
$this->listeners[$event_name][$priority][] = [
'callable' => $listener,
];
$this->unsorted[$event_name] = TRUE;
}
/**
* {@inheritdoc}
*/
public function removeListener($event_name, $listener) {
if (!isset($this->listeners[$event_name])) {
return;
}
foreach ($this->listeners[$event_name] as $priority => $definitions) {
foreach ($definitions as $key => $definition) {
if (!isset($definition['callable'])) {
if (!$this->container
->initialized($definition['service'][0])) {
continue;
}
$definition['callable'] = [
$this->container
->get($definition['service'][0]),
$definition['service'][1],
];
}
if (is_array($definition['callable']) && isset($definition['callable'][0]) && $definition['callable'][0] instanceof \Closure && !$listener instanceof \Closure) {
$definition['callable'][0] = $definition['callable'][0]();
}
if (is_array($definition['callable']) && isset($definition['callable'][0]) && !$definition['callable'][0] instanceof \Closure && is_array($listener) && isset($listener[0]) && $listener[0] instanceof \Closure) {
$listener[0] = $listener[0]();
}
if ($definition['callable'] === $listener) {
unset($definitions[$key]);
}
}
if ($definitions) {
$this->listeners[$event_name][$priority] = $definitions;
}
else {
unset($this->listeners[$event_name][$priority]);
}
}
}
/**
* {@inheritdoc}
*/
public function addSubscriber(EventSubscriberInterface $subscriber) {
foreach ($subscriber->getSubscribedEvents() as $event_name => $params) {
if (is_string($params)) {
$this->addListener($event_name, [
$subscriber,
$params,
]);
}
elseif (is_string($params[0])) {
$this->addListener($event_name, [
$subscriber,
$params[0],
], $params[1] ?? 0);
}
else {
foreach ($params as $listener) {
$this->addListener($event_name, [
$subscriber,
$listener[0],
], $listener[1] ?? 0);
}
}
}
}
/**
* {@inheritdoc}
*/
public function removeSubscriber(EventSubscriberInterface $subscriber) {
foreach ($subscriber->getSubscribedEvents() as $event_name => $params) {
if (is_array($params) && is_array($params[0])) {
foreach ($params as $listener) {
$this->removeListener($event_name, [
$subscriber,
$listener[0],
]);
}
}
else {
$this->removeListener($event_name, [
$subscriber,
is_string($params) ? $params : $params[0],
]);
}
}
}
}
Classes
Title | Deprecated | Summary |
---|---|---|
ContainerAwareEventDispatcher | A performance optimized container aware event dispatcher. |
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