Async.md

Async Jobs

All events are published in RabbitMQ through App\Infrastructure\Shared\Event\Publisher\AsyncEventPublisher. The reason of this is that others can consume this events in background.

How it works?

The AsyncEventPublisher implements 2 important interfaces.

• Broadway\EventHandling\EventListener
  • It binds this class to the EventBus and invoke method handle that collect the events in memory inside the class.
• Symfony\Component\EventDispatcher\EventSubscriberInterface
  • This binds the class to {KernelEvents,ConsoleEvents}::TERMINATE Symfony events and invoke method publish

By that way we're sending the messages to RabbitMQ after respond to the client so we don't lock the client for things not required to wait.

Consume this events

Create you own consumer:

<?php

declare(strict_types=1);

namespace App\Demo\Infrastructure\Event\Consumer;

use OldSound\RabbitMqBundle\RabbitMq\ConsumerInterface;
use PhpAmqpLib\Message\AMQPMessage;

class DemoEventsConsumer implements ConsumerInterface
{
    public function execute(AMQPMessage $msg): void
    {
        var_dump(unserialize($msg->body));
    }
}

Configure you consumer:

old_sound_rabbit_mq:
	...
    multiple_consumers:
        events:
            ....
            queues:
                 ....
+                var_dump_all_events:
+                    name: var_dump_all_events
+                    routing_keys:
+                        - 'App.Domain.#'
+                    callback: App\Demo\Infrastructure\Event\Consumer\DemoEventsConsumer

Running the Consumer

By default all consumers are invoked with container:

docker-compose.yml

  workers:
    image: jorge07/alpine-php:7.2-dev-sf
    volumes:
      - .:/app
    command: ['/app/bin/console', 'rabbitmq:multiple-consumer', 'events']

To run just our new consumer: Inside docker container: ./bin/console rabbitmq:consumer var_dump_all_events

Full doc with much better example here: https://github.com/php-amqplib/RabbitMqBundle

Routing keys

So simple, it replaces namespaces \ for ., example:

App\User\Domain\Event\UserWasCreated -> App.User.Domain.Event.UserWasCreated

You can bind you consumer to:

• All events: #
• All domain events: #.Domain.#
• All domain context boundary events: #.User.Domain.#
• A one particular event: App.User.Domain.Event.UserWasCreated
• Combination of keys:
  • App.User.Domain.#
  • App.Payments.Domain.#
  • App.Cart.Domain.Event.OrderWasCreated
  • App.Cart.Domain.Event.OrderWasCanceled

Much better explained in the official documentation: https://www.rabbitmq.com/tutorials/tutorial-five-python.html