Previously, one had to be careful to check if the debug.stopwatch
service was available before using it. Otherwise, the application
would break in the prod environment.
* 2.2:
Fix some annotates
[FrameworkBundle] made sure that the debug event dispatcher is used everywhere
[HttpKernel] remove unneeded strtoupper
updated the composer install command to reflect changes in Composer
Conflicts:
src/Symfony/Component/Console/Application.php
src/Symfony/Component/Console/Command/Command.php
src/Symfony/Component/Console/Input/InputDefinition.php
src/Symfony/Component/CssSelector/Node/CombinedSelectorNode.php
src/Symfony/Component/Form/Form.php
src/Symfony/Component/HttpKernel/Debug/ErrorHandler.php
src/Symfony/Component/HttpKernel/DependencyInjection/RegisterListenersPass.php
src/Symfony/Component/HttpKernel/Tests/DependencyInjection/RegisterListenersPassTest.php
src/Symfony/Component/Locale/Locale.php
src/Symfony/Component/Locale/README.md
src/Symfony/Component/Locale/Stub/DateFormat/FullTransformer.php
The ContainerAwareTraceableEventDispatcher class was tied to both the
Symfony container and the HttpKernel profiler. It made it non reusable
in another context.
The new TraceableEventDispatcher only keeps the HttpKernel profiler
integration and is able to wrap any other event dispatcher. It makes it
reusable in frameworks using the Symfony HttpKernel component like
Silex.
The only drawback is that we don't have access to the listener
priorities in the collected data anymore (but the listeners are still
ordered correctly). The change is still worth it I think.
Doctrine's EventManager implementation has several advantages over the
EventDispatcher implementation of Symfony2. Therefore I suggest that we
use their implementation.
Advantages:
* Event Listeners are objects, not callbacks. These objects have handler
methods that have the same name as the event. This helps a lot when
reading the code and makes the code for adding an event listener shorter.
* You can create Event Subscribers, which are event listeners with an
additional getSubscribedEvents() method. The benefit here is that the
code that registers the subscriber doesn't need to know about its
implementation.
* All events are defined in static Events classes, so users of IDEs benefit
of code completion
* The communication between the dispatching class of an event and all
listeners is done through a subclass of EventArgs. This subclass can be
tailored to the type of event. A constructor, setters and getters can be
implemented that verify the validity of the data set into the object.
See examples below.
* Because each event type corresponds to an EventArgs implementation,
developers of event listeners can look up the available EventArgs methods
and benefit of code completion.
* EventArgs::stopPropagation() is more flexible and (IMO) clearer to use
than notifyUntil(). Also, it is a concept that is also used in other
event implementations
Before:
class EventListener
{
public function handle(EventInterface $event, $data) { ... }
}
$dispatcher->connect('core.request', array($listener, 'handle'));
$dispatcher->notify('core.request', new Event(...));
After (with listeners):
final class Events
{
const onCoreRequest = 'onCoreRequest';
}
class EventListener
{
public function onCoreRequest(RequestEventArgs $eventArgs) { ... }
}
$evm->addEventListener(Events::onCoreRequest, $listener);
$evm->dispatchEvent(Events::onCoreRequest, new RequestEventArgs(...));
After (with subscribers):
class EventSubscriber
{
public function onCoreRequest(RequestEventArgs $eventArgs) { ... }
public function getSubscribedEvents()
{
return Events::onCoreRequest;
}
}
$evm->addEventSubscriber($subscriber);
$evm->dispatchEvent(Events::onCoreRequest, new RequestEventArgs(...));
* The register() method on all listeners has been removed
* Instead, the information is now put directly in the DIC tag
For instance, a listener on core.request had this method:
public function register(EventDispatcher $dispatcher, $priority = 0)
{
$dispatcher->connect('core.response', array($this, 'filter'), $priority);
}
And this tag in the DIC configuration:
<tag name="kernel.listener" />
Now, it only has the following configuration:
<tag name="kernel.listener" event="core.response" method="filter" priority="0" />
The event and method attributes are now mandatory.
