Usage

Here you will find some examples of how to use the bundle. But we provide only examples for specific symfo

Info

You can find out more about event sourcing in the library documentation. This documentation is limited to bundle integration and configuration.

Repository

You can access the specific repositories using the RepositoryManager::get. Or inject directly the right repository via argument name injection. For our aggregate Hotel it would be $hotelRepository.

namespace App\Hotel\Infrastructure\Controller;

use Patchlevel\EventSourcing\Aggregate\Uuid;
use Patchlevel\EventSourcing\Repository\Repository;
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\HttpKernel\Attribute\AsController;

#[AsController]
final class HotelController
{
    public function __construct(
        /** @var Repository<Hotel> */
        private readonly Repository $hotelRepository,
    ) {
    }

    public function doStuffAction(Uuid $hotelId): Response
    {
        $hotel = $this->hotelRepository->load($hotelId);

        $hotel->doStuff();

        $hotelRepository->save($hotel);

        return new Response();
    }
}

Subscriber

A subscriber can be used to send an email when a guest is checked in:

namespace App\Hotel\Application\Subscriber;

use Patchlevel\EventSourcing\Attribute\Subscriber;
use Patchlevel\EventSourcing\Subscription\RunMode;

#[Subscriber('send_check_in_email', RunMode::FromNow)]
class SendCheckInEmailSubscriber
{
    // ...
}

If you have the symfony default service setting with autowireand autoconfiger enabled, the subscriber is automatically recognized and registered at the Subscriber attribute. Otherwise you have to define the subscriber in the symfony service file:

services:
    App\Hotel\Application\Subscriber\SendCheckInEmailSubscriber:
      tags:
        - event_sourcing.subscriber

Event Bus Listener

A process can be for example used to send an email when a guest is checked in:

namespace App\Hotel\Application\Listener;

use App\Hotel\Domain\Event\GuestIsCheckedIn;
use Patchlevel\EventSourcing\Attribute\Subscribe;
use Patchlevel\EventSourcing\Message\Message;
use Patchlevel\EventSourcingBundle\Attribute\AsListener;
use Symfony\Component\Mailer\MailerInterface;
use Symfony\Component\Mime\Email;

use function sprintf;

#[AsListener]
final class SendCheckInEmailListener
{
    private function __construct(private MailerInterface $mailer)
    {
    }

    #[Subscribe(GuestIsCheckedIn::class)]
    public function __invoke(Message $message): void
    {
        $event = $message->event();

        $email = (new Email())
            ->from('[email protected]')
            ->to('[email protected]')
            ->subject('Guest is checked in')
            ->text(sprintf('A new guest named "%s" is checked in', $event->guestName()));

        $this->mailer->send($email);
    }
}

If you have the symfony default service setting with autowireand autoconfiger enabled, the listener is automatically recognized and registered at the AsListener attribute. Otherwise you have to define the listener in the symfony service file:

services:
    App\Hotel\Application\Listener\SendCheckInEmailListener:
      tags:
        - event_sourcing.listener

Priority

You can also determine the priority in which the listeners are executed. The higher the priority, the earlier the listener is executed. You have to add the tag manually and specify the priority.

namespace App\Hotel\Application\Listener;

#[AsListener(priority: 16)]
final class SendCheckInEmailListener
{
    // ...
}

services:
    App\Hotel\Application\Listener\SendCheckInEmailListener:
      autoconfigure: false
      tags:
        - name: event_sourcing.listener
          priority: 16

Warning

You have to deactivate the autoconfigure for this service, otherwise the service will be added twice.

Normalizer

This bundle adds more Symfony specific normalizers in addition to the existing built-in normalizers.

Note

You can find the other build-in normalizers here

Uuid

With the Uuid Normalizer, as the name suggests, you can convert Symfony Uuid objects to a string and back again.

use Patchlevel\EventSourcingBundle\Normalizer\SymfonyUuidNormalizer;
use Symfony\Component\Uid\Uuid;

final class DTO
{
    #[SymfonyUuidNormalizer]
    public Uuid $id;
}

Warning

The symfony uuid don't implement the AggregateId interface, so it can be used as aggregate id.

Tip

Use the Uuid implementation and IdNormalizer from the library to use it as an aggregate id.

Upcasting

use Patchlevel\EventSourcing\Serializer\Upcast\Upcast;
use Patchlevel\EventSourcing\Serializer\Upcast\Upcaster;

final class ProfileCreatedEmailLowerCastUpcaster implements Upcaster
{
    public function __invoke(Upcast $upcast): Upcast
    {
        // ignore if other event is processed
        if ($upcast->eventName !== 'profile_created') {
            return $upcast;
        }

        return $upcast->replacePayloadByKey('email', strtolower($upcast->payload['email']));
    }
}

If you have the symfony default service setting with autowireand autoconfigure enabled, the upcaster is automatically recognized and registered at the Upcaster interface. Otherwise you have to define the upcaster in the symfony service file:

services:
    App\Upcaster\ProfileCreatedEmailLowerCastUpcaster:
      tags:
        - event_sourcing.upcaster

Message Decorator

We want to add the header information which user was logged in when this event was generated.

use Patchlevel\EventSourcing\Message\Message;
use Patchlevel\EventSourcing\Repository\MessageDecorator\MessageDecorator;
use Symfony\Component\Security\Core\Authentication\Token\Storage\TokenStorageInterface;

final class LoggedUserDecorator implements MessageDecorator
{
    public function __construct(
        private readonly TokenStorageInterface $tokenStorage,
    ) {
    }

    public function __invoke(Message $message): Message
    {
        $token = $this->tokenStorage->getToken();

        if (!$token) {
            return $message;
        }

        return $message->withHeader(new UserHeader($token->getUsername()));
    }
}

If you have the symfony default service setting with autowireand autoconfigure enabled, the message decorator is automatically recognized and registered at the MessageDecorator interface. Otherwise you have to define the message decorator in the symfony service file:

services:
  App\Message\Decorator\LoggedUserDecorator:
    tags:
      - event_sourcing.message_decorator