README

Small Subscriber/Publisher messaging system.

Package implements One-way Message Exchange Pattern and Request-Reply Message Exchange Pattern.

Requirement

This library package requires PHP 5.4 or later.

Installation

$ composer require gigi/event-request-response

Usage

Create Messenger instance (singleton)

use gigi\events\classes\Messenger;

$handler = Messenger::getInstance();

Subscribe to messages

$handler->subscribe('message.test', function ($message) {
    // do something with message
    // stops further message processing
    $message->setIsHandled(true);

    // optionally return mixed response
    // Will be accessible in reply object (Message::getData())
    return 'Data to return';
});

Create message

use gigi\events\classes\Message;

$message = new Message('message.test', 'Mixed data to send');

Use one of three methods to publish $message

// one-way notifier
$handler->request($message);

// request-response notifier
// Returns array of Messages
$result = $handler->requestReply($message);

// request-response notifier
// Returns only first reply (Message object)
// Use if Your don't care of who can return an answer
// for example if you want to get list of all users ('users.get.all')
// or you know for sure that only one subscriber listening

$result = $handler->requestFirstReply($message);

For detailed usage see examples/singleton.php.

If singleton makes you cry or your project has own dependency injection container inject gigi\classes\MessageHandler to new instances of gigi\classes\Publisher and gigi\classes\Subscriber. See examples/di.php

Usage with Yii2 Framework

Add Publisher and Subscriber components to config (config/web.php)

return [
    ...
    'components' => [
        ...
        'subscriber' => 'gigi\events\classes\Subscriber',
        'publisher'  => 'gigi\events\classes\Publisher',
        ...

Add gigi\events\classes\MessageHandlerInterface to DI container. For more information about Yii2 DI container see http://www.yiiframework.com/doc-2.0/guide-concept-di-container.html

\Yii::$container->setSingleton(
    'gigi\events\interfaces\MessageHandlerInterface',
    'gigi\events\classes\MessageHandler'
);

Subscribing for event:

\Yii::$app->get('subscriber')->subscribe($event, $handler);

Publishing:

...
use gigi\events\classes\Message;
...

/** @var \gigi\events\interfaces\MessageInterface $message */
$message = new Message($messageName, $data);

// async
\Yii::$app->get('publisher')->request($message);

// all replies
\Yii::$app->get('publisher')->requestReply($message);

// first reply
\Yii::$app->get('publisher')->requestFirstReply($message);

Or implement you own classes for interfaces...

Enjoy :)