AsynchronousBundle

This bundle integrates async component with the Symfony framework

Install with

1
composer require simple-bus/asynchronous-bundle
 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
class AppKernel extends Kernel
{
    public function registerBundles()
    {
        $bundles = array(
            ...
            new SimpleBus\AsynchronousBundle\SimpleBusAsynchronousBundle(),
            ...
        );
    }
}

Configuration

@TODO Show the standard config

Public services

@TODO What services exists when the bundle is enabled.

Getting started

Introduction

This bundle defines a new command and event bus, to be used for processing asynchronous commands and events. It also adds middleware to existing the command and event buses which publishes messages to be processed asynchronously. See also the documentation of SimpleBus/Asynchronous.

First, enable the SimpleBusAsynchronousBundle in your AppKernel class.

Provide an object serializer

The first thing you need to do is to provide a service that is able to serialize any object. This service needs to implement SimpleBus\Serialization\ObjectSerializer.

1
2
3
# in config.yml
simple_bus_asynchronous:
    object_serializer_service_id: your_object_serializer

Note

Use an existing object serializer

Instead of creating your own object serializer, you should install the SimpleBus/JMSSerializerBundle. Once you register this bundle in your AppKernel as well, it will automatically register itself as the preferred object serializer. So if you do, don’t forget to remove the key simple_bus_asynchronous.object_serializer_service_id from your config file.

Provide message publishers

Next, you need to define services that are able to publish commands and events, for example to some message queue. These services should both implement SimpleBus\Asynchronous\Publisher\Publisher. When you have defined them as services, mention their service id in the configuration:

1
2
3
4
5
6
# in config.yml
simple_bus_asynchronous:
    commands:
        publisher_service_id: your_command_publisher
    events:
        publisher_service_id: your_event_publisher

Note

Use existing publishers

Instead of writing your own publishers, you can use existing publisher implementations.

As part of SimpleBus a RabbitMQBundle has been provided which automatically registers command and event publishers to publish serialized messages to a RabbitMQ exchange.

Logging

To get some insight into what goes on in the consumer process, enable logging:

1
2
3
4
5
6
7
8
# in config.yml
simple_bus_asynchronous:
    commands:
        ...
        logging: ~
    events:
        ...
        logging: ~

This will log consumed messages to the asynchronous_command_bus and asynchronous_event_bus channels respectively.

Choose event strategy

When handling events you have two predefined strategies to choose from. Either you publish all events to the message queue (always strategy) or you only publish the events that have a registered asynchronous subscriber (predefined strategy). If your application is the only one that is consuming messages you should consider using the predefined strategy. This will reduce the message overhead on the message queue.

1
2
3
simple_bus_asynchronous:
    events:
        strategy: 'predefined' # default: 'always'

You can also use Your own strategy by defining custom strategy_service_id

1
2
3
4
simple_bus_asynchronous:
    events:
        strategy:
            strategy_service_id: your_strategy_service

Using Autowiring

This bundle can be used with Symfony’s Autowiring out of the box.

Simply inject SimpleBus\AsynchronousBundle\Bus\AsynchronousCommandBus or SimpleBus\AsynchronousBundle\Bus\AsynchronousEventBus in your service.