Manual Control

To manually manage domain events, you can use DomainEventAwareEntityManagerInterface in place of the regular EntityManagerInterface. It adds several methods to the Entity Manager that you can use to manage domain event dispatching.

Manual Dispatching

You can disable automatic dispatching on flush() by calling setAutoDispatchDomainEvents(false).

use Rekalogika\DomainEvent\DomainEventAwareEntityManagerInterface;

/** @var DomainEventAwareEntityManagerInterface $entityManager */

$entityManager->setAutoDispatchDomainEvents(false);

// ...

$entityManager->dispatchPreFlushDomainEvents();
$entityManager->flush();
$entityManager->dispatchPostFlushDomainEvents();

note

Immediate dispatching is dispatched outside DomainEventAwareEntityManager, and therefore unaffected by setAutoDispatchDomainEvents().

Clearing the Events

If the domain event queues are not empty at the end of the request, DomainEventEntityManager will throw UndispatchedEventsException. To prevent that from happening, if you disable auto-dispatch, you need to make sure that you dispatch both pre-flush and post-flush events as above. Alternatively, you can clear the events if you don't want them dispatched:

use Rekalogika\DomainEvent\DomainEventAwareEntityManagerInterface;

/** @var DomainEventAwareEntityManagerInterface $entityManager */

$entityManager->setAutoDispatchDomainEvents(false);

// ...

$entityManager->flush();
$entityManager->clearDomainEvents();

note

In the event of an uncaught error, the framework will automatically clear undispatched events using the kernel.exception and console.error events, so in such cases, you don't have to handle that manually. But if you catch an exception that previously caused pending events not to be dispatched, you need to manually clear the events.

Getting the Events From the Queue and Dispatching Them Elsewhere

You can get the undispatched events in the queue by calling popDomainEvents().

use Rekalogika\DomainEvent\DomainEventAwareEntityManagerInterface;

/** @var DomainEventAwareEntityManagerInterface $entityManager */

$events = $entityManager->popDomainEvents();

note

As it suggests, popDomainEvents() also removes the events from the queue.

Then, you can dispatch them in another place, for example, in another process, or at the end of a batch process.

use Rekalogika\DomainEvent\DomainEventAwareEntityManagerInterface;

/** @var DomainEventAwareEntityManagerInterface $entityManager */

$entityManager->recordDomainEvent($events);

$entityManager->dispatchPreFlushDomainEvents();
$entityManager->flush();
$entityManager->dispatchPostFlushDomainEvents();

You might find the DomainEventStore object useful. You can use it to store the events in transit. It handles EquatableDomainEventInterface and will automatically discard duplicate events.

use Rekalogika\DomainEvent\DomainEventAwareEntityManagerInterface;
use Rekalogika\DomainEvent\Model\DomainEventStore;

/** @var DomainEventAwareEntityManagerInterface $entityManager */

$domainEventStore = new DomainEventStore();

// a batch process
foreach (...) {
    // ...
    $domainEventStore->add($entityManager->popDomainEvents());
}

// ...

// now at the end of the batch process

$entityManager->recordDomainEvent($domainEventStore);
$entityManager->dispatchPreFlushDomainEvents();
$entityManager->flush();
$entityManager->dispatchPostFlushDomainEvents();

Multiple Entity Managers

When working with multiple entity managers, usually the ManagerRegistry is used to get the correct entity manager. This method still works with domain events without any change.

However, if you need the domain-event-specific methods, you can use DomainEventAwareManagerRegistry in place of ManagerRegistry. It adds several methods to the registry that you can use to manage domain event dispatching:

• getDomainEventAwareManager()
• getDomainEventAwareManagers()
• getDomainEventAwareManagerForClass()

These are basically the same as their counterparts in ManagerRegistry, only return DomainEventAwareObjectManager instead of ObjectManager.