* vicb/cfg_rebase:
[Config] Ability to add and override node types without having to subclass NodeBuilder
[DoctrineBundle] Fix some typos
[SwiftMailerBundle] Fix a merge issue in the configuration
Tweak PHPDocs in the extension configuration files
[Config] Component refactoring
The onCore* events are fired at some pre-defined points during the
handling of a request. At this is more important than the fact
that you can change things from the event.
The Config component API have changed and the extension configuration files must be updated accordingly:
1. Array nodes must enclosed their children definition in ->children() ... ->end() calls:
Before:
$treeBuilder->root('zend', 'array')
->arrayNode('logger')
->scalarNode('priority')->defaultValue('INFO')->end()
->booleanNode('log_errors')->defaultFalse()->end()
->end();
After:
$treeBuilder->root('zend', 'array')
->children()
->arrayNode('logger')
->children()
->scalarNode('priority')->defaultValue('INFO')->end()
->booleanNode('log_errors')->defaultFalse()->end()
->end()
->end()
->end();
2. The 'builder' method (in NodeBuilder) has been dropped in favor of an 'append' method (in ArrayNodeDefinition)
Before:
$treeBuilder->root('doctrine', 'array')
->arrayNode('dbal')
->builder($this->getDbalConnectionsNode())
->end();
After:
$treeBuilder->root('doctrine', 'array')
->children()
->arrayNode('dbal')
->append($this->getDbalConnectionsNode())
->end()
->end();
3. The root of a TreeBuilder is now an NodeDefinition (and most probably an ArrayNodeDefinition):
Before:
$root = $treeBuilder->root('doctrine', 'array');
$this->addDbalSection($root);
public function addDbalSection(NodeBuilder $node)
{
...
}
After:
$root = $treeBuilder->root('doctrine', 'array');
$this->addDbalSection($root);
public function addDbalSection(ArrayNodeDefinition $node)
{
...
}
4. The NodeBuilder API has changed (this is seldom used):
Before:
$node = new NodeBuilder('connections', 'array');
After:
The recommended way is to use a tree builder:
$treeBuilder = new TreeBuilder();
$node = $treeBuilder->root('connections', 'array');
An other way would be:
$builder = new NodeBuilder();
$node = $builder->node('connections', 'array');
Some notes:
- Tree root nodes should most always be array nodes, so this as been made the default:
$treeBuilder->root('doctrine', 'array') is equivalent to $treeBuilder->root('doctrine')
- There could be more than one ->children() ... ->end() sections. This could help with the readability:
$treeBuilder->root('doctrine')
->children()
->scalarNode('default_connection')->end()
->end()
->fixXmlConfig('type')
->children()
->arrayNode('types')
....
->end()
->end()
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(...));
