TNC EventDispatcher

tnc-event-dispatcher is a alternative of symfony-event-dispatcher for supporting asynchronous and unified structured events, It works as same as symfony-event-dispatcher, has same user interface with a few more options, can replace symfony-event-dispatcher seamlessly.
For more details can check the Document.

User cases of tnc-event-dispatcher:

• Heavy Listeners
• Distrubuted Listeners
• Shared Events across multiple systems
• Structred data collecting
• ...

tnc-event-dispatcher includes following core components: Dispatcher, Serializer, EndPoint, Receiver.
It is highly inspired by symfony-event-dispatcher, But not limited on that, symfony-event-dispatcher is one of the Dispatcher implementations of tnc-event-dispatcher, It intends to support other Event Dispatcher implementations as well.

How to install?

Requirements

• PHP 5.6+

Install From Composer

Since the vendor namespace "tnc" was occupied by someone else, We can not publish to Packagist, You need to add this git repository url to "repository" of your composer.json first.

"repositories": [
    {
        "type": "vcs",
        "url":  "[email protected]:thenetcircle/tnc-event-dispatcher.git"
    }
]

Then run install command.

> composer require tnc/event-dispatcher

How to use?

<?php
namespace TNC\EventDispatcher;

try {
    /**
     * 1. Initialize Serializer
     * 
     * Serializer is using to serialize your event to be a string.
     * It includes a couple of Normalizers and a Formatter.
     */     
    # Specify Normalizers
    $supportedNormalizers = [
        new Serialization\Normalizers\ActivityStreams\ActivityStreamsWrappedEventNormalizer(),
        new Serialization\Normalizers\ActivityStreams\ActivityStreamsNormalizer()
    ];
    # Specify Serialization Format
    $formatter  = new Serialization\Formatters\JsonFormatter();
    # Initialize Serializer
    $serializer = new Serializer($supportedNormalizers, $formatter);


    /**
     * 2. Initialize EndPoint
     * 
     * If you are going to dispatch a async event, which needs a EndPoint to hold the request and send back to Receiver.
     * Mostly the EndPoint is a Queue, such as Redis, Rabbitmq, Kafka or EventBus (https://github .com/thenetcircle/event-bus)
     */
    $endPoint = new EndPoints\EventBusEndPoint('http://localhost:8000');


    /**
     * 3. Initialize tnc-event-dispatcher, And add some Listeners
     */
    $dispatcher = new Dispatchers\SymfonyImpl\EventDispatcher($serializer, $endPoint);
    # Suppose we have a Symfony Event Listener and a Event Subscriber here
    $dispatcher->addListener('message.send', new SymfonyEventListener());
    $dispatcher->addSubscriber(new SymfonyEventSubscriber());

    /**
     * 4. Dispatch Events
     */
    $dispatcher->dispatch(
        'message.send',
        new AsyncEvent(
            [
                'messageId'   => '1',
                'messageBody' => 'abc'
            ]
        )
    );
}
catch (\Exception $e) {
    // Handling Exception
}

/**
 * 5. Receiving and handling the AsyncEvent
 * 
 * After the Event dispatched to the EndPoint, It will be delivered to the Receiver asynchronously.
 * Following are Receiver part, Which could be running on another PHP process
 */
try {
    # Initialize a Receiver(use EventBusReceiver as a example here, could be RabbitMQReceiver, RedisReceiver, ...)
    $receiver = new Receivers\EventBusReceiver();
    # Set Dispatcher we defined before
    $receiver->withDispatcher($dispatcher);
    # Dispatch the serliazed-event we received from the EndPoint
    $receiver->dispatch($serliazedEvent);
}
catch (\Exception $e) {
    // Handling Exception
}

Contributing

Feedbacks and pull requests are welcome and appreciative. You can contact me by mail or slack or open a issue.
For major changes, please open an issue first to discuss what you would like to change.

Change Logs

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