Messaging Client

This is a simple client to publish and consumes messages from a Message Queue server.

Features

• Low code to publish and consume messages
• Messages, Queues and Connector objects are decoupled
• Easy to implement new connectors

┌─────────────────┐                  ┌────────────────────────┐
│                 │                  │  Envelope              │
│                 │                  │                        │
│                 │                  │                        │
│                 │                  │   ┌─────────────────┐  │
│                 │   publish()      │   │      Pipe       │  │
│                 ├─────────────────▶│   └─────────────────┘  │
│                 │                  │   ┌─────────────────┐  │
│                 │                  │   │     Message     │  │
│                 │                  │   └─────────────────┘  │
│                 │                  │                        │
│                 │                  └────────────────────────┘
│    Connector    │
│                 │
│                 │
│                 │       consume()     ┌─────────────────┐
│                 │◀────────────────────│      Pipe       │
│                 │                     └─────────────────┘
│                 │
│                 │
│                 │
└─────────────────┘

Implemented Connectors

Connector	URL / Documentation	Composer Package
Mock	docs/mock-connector.md	-
RabbitMQ	https://github.com/byjg/rabbitmq-client	byjg/rabbitmq-client
Redis	https://github.com/byjg/redis-queue-client	byjg/redis-queue-client

Usage

Publish

<?php
// Register the connector and associate with a scheme
ConnectorFactory::registerConnector(MockConnector::class);

// Create a connector
$connector = ConnectorFactory::create(new Uri("mock://local"));

// Create a queue
$pipe = new Pipe("test");
$pipe->withDeadLetter(new Pipe("dlq_test"));

// Create a message
$message = new Message("Hello World");

// Publish the message into the queue
$connector->publish(new Envelope($pipe, $message));

Consume

<?php
// Register the connector and associate with a scheme
ConnectorFactory::registerConnector(MockConnector::class);

// Create a connector
$connector = ConnectorFactory::create(new Uri("mock://local"));

// Create a queue
$pipe = new Pipe("test");
$pipe->withDeadLetter(new Pipe("dlq_test"));

// Connect to the queue and wait to consume the message
$connector->consume(
    $pipe,                                 // Queue name
    function (Envelope $envelope) {         // Callback function to process the message
        echo "Process the message";
        echo $envelope->getMessage()->getBody();
        return Message::ACK;
    },
    function (Envelope $envelope, $ex) {    // Callback function to process the failed message
        echo "Process the failed message";
        echo $ex->getMessage();
        return Message::REQUEUE;
    }
);

The consume method will wait for a message and call the callback function to process the message. If there is no message in the queue, the method will wait until a message arrives.

If you want to exit the consume method, just return Message::ACK | Message::EXIT from the callback function.

Possible return values from the callback function:

• Message::ACK - Acknowledge the message and remove from the queue
• Message::NACK - Not acknowledge the message and remove from the queue. If the queue has a dead letter queue, the message will be sent to the dead letter queue.
• Message::REQUEUE - Requeue the message
• Message::EXIT - Exit the consume method

Consumer Client

You can simplify the consume method by using the ConsumerClientTrait. See more details in the docs/consumer-client-trait.md.

Connectors

The connectors are the classes responsible to connect to the message queue server and send/receive messages.

All connector have the following interface:

<?php
interface ConnectorInterface
{
    public function setUp(Uri $uri);

    public function getDriver();

    public function publish(Envelope $envelope);

    public function consume(Pipe $pipe, \Closure $onReceive, \Closure $onError, $identification = null);
}

There is no necessary call the method getDriver() because the method publish() and consume() will call it automatically. Use the method getDriver() only if you need to access the connection directly.

Dependencies

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Open source ByJG