Drest comes shipped with an event manager that wraps around the \Doctrine\Common\EventManager. It has the facility to register listeners for a specific event, or create and register a subscriber with a declaration of all events they’re subscribed to.

To use the event system with drest you simply have to register an event manager object when constructing your drest manager.

$evm = new Drest\Event\Manager();
// .. attach listeners / subscribers ..
$drestManager = \Drest\Manager::create(
    \Drest\EntityManagerRegistry::getSimpleManagerRegistry($em),
    $drestConfig,
    $evm
);

For further information about how to use the doctrine event system click here

Lifecycle Event Listeners

There are a number of hooks during the life cycle of a dispatched drest request see event types that you can register listeners to. All listeners will be injected with a corresponding arguments object, which typically provides access to the service action object (although this may not always be the case).

// Once a request has been successfully serviced, send a log message
class MyEventListener
{
    // see \Drest\Event\PostDispatchArgs for info on available arguments
    public function postDispatch(\Drest\Event\PostDispatchArgs $args)
    {
        MyLogger::log('Request was completed', $args->getService()->getRequest());
    }
}

$evm = new Drest\Event\Manager();
$evm->addListener(array(\Drest\Event\Events::POST_DISPATCH), new MyEventListener());

Subscribers

As the Doctrine event system also has the concept of event subscribers, you can also leverage this with Drest. These must extend \Drest\Event\Subscriber and implement a getSubscribedEvents() method that return an array of events to be subscribed to.

// Log each request as it comes in
class MyEventSubscriber extends \Drest\Event\Subscriber
{
    // see \Drest\Event\PostDispatchArgs for info on available arguments
    public function preDispatch(\Drest\Event\PostDispatchArgs $args)
    {
        MyLogger::log('Request was started', $args->getService()->getRequest());
    }

    public function getSubscribedEvents()
    {
        return array(\Drest\Event\Events::POST_DISPATCH);
    }
}

$evm = new Drest\Event\Manager();
$evm->addSubscriber(new MyEventSubscriber());

Event Types

The following events are available (and triggered in their respective order) to register listeners / subscribers to.

PreDispatch

Event is triggered before anything else occurs on dispatch of the drest manager (before a routing lookup). This event will ALWAYS trigger.

PreRouting

This event is triggered before any routing occurs on the request object provided. This will be triggered regardless of whether a named route has been used.

PostRouting

This event is triggered after a routing lookup has occurred on the request object provided. This will be triggered regardless of whether a named route has been used.

PreServiceAction

This event is triggered before the service action call is executed. If the request has failed on route look up this event WILL NOT be triggered.

PostServiceAction

This event is triggered after the service action call is executed. If the request has failed on route look up this event WILL NOT be triggered.

PostDispatch

Once a request has successfully dispatched through the drest manager, this event will be triggered. This event will ALWAYS trigger. Even in the event of an error.