Producers¶

Producers add messages to a driver backed for the consumer to pick up and handle.

interface Producer¶

Namespace:	PMG\Queue

send(PMG\Queue\Message $message)¶

Send a message to a driver backend.

Parameters:	$message – The message to send into the queue
Throws:	PMG\Queue\Exception\QueueNotFound if the message can’t be routed to an appropriate queue.

The default producer implementation takes a driver and a router as its constructor arguments and uses the router (explained below) to send its messages into a drivers specific queue.

<?php

use PMG\Queue\DefaultProducer;
use PMG\Queue\Router\SimpleRouter;

$router = new SimpleRouter('queueName');

/** @var PMG\Queue\Driver $driver */
$producer = new DefaultProdicer($driver, $router);

Routers¶

pmg/queue is built with multi-queue support in in mind. To accomplish that on the producer side of things an implementation of PMG\Queue\Router is used.

interface Router¶

Namespace:	PMG\Queue

queueFor(PMG\Queue\Message $message)¶

Looks a queue name for a given message.

Parameters:	$message – the message to route
Returns:	A string queue name if found, `null` otherwise.
Return type:	string or null

Routing all Message to a Single Queue¶

Use PMG\Queue\SimpleRouter, which takes a queue name in the constructor and always returns it.

<?php
use PMG\Queue\Router\SimpleRouter;

// all message will go in the "queueName" queue
$router = new SimpleRouter('queueName');

Routing Messages Based on Their Name¶

Use PMG\Queue\MappingRouter, which takes a map of message name => queue name pairs to its constructor.

<?php

use PMG\Queue\Router\MappingRouter;

$router = new MappingRouter([
    // the `SendAlert` message will go into the `Alerts` queue
    'SendAlert' => 'Alerts',
]);

Falling Back to a Default Queue¶

To avoid QueueNotFound exceptions, it’s often a good idea to use PMG\Queue\Router\FallbackRouter.

<?php

use PMG\Queue\DefaultProducer;
use PMG\Queue\SimpleMessage;
use PMG\Queue\Router\FallbackRouter;
use PMG\Queue\Router\MappingRouter;

$router = new FallbackRouter(new MappingRouter([
    'SendAlert' => 'Alerts',
]), 'defaultQueue');

$producer = new DefaultProducer($driver, $router);

// goes into the `Alerts` queue
$producer->send(new SimpleMessage('SendAlert'));

// goes into `defaultQueue`
$producer->send(new SimpleMessage('OtherThing'));