Created by Jurian Sluiman and Michaël Gallego

• Zend Framework 2
• SlmQueue
• Pda Pheanstalk

First, install SlmQueue (instructions here). Then, add the following line into your composer.json file:

"require": {
	"slm/queue-beanstalkd": "0.4.*"
}

Then, enable the module by adding SlmQueueBeanstalkd in your application.config.php file. You may also want to configure the module: just copy the slm_queue_beanstalkd.local.php.dist (you can find this file in the config folder of SlmQueueBeanstalkd) into your config/autoload folder, and override what you want.

Before reading SlmQueueBeanstalkd documentation, please read SlmQueue documentation.

(Don't forget to first install Beanstalkd, and to run the daemon program on the server)

Copy the slm_queue_beanstalkd.local.php.dist file to your config/autoload folder, and follow the instructions.

SlmQueueBeanstalkd provides an interface for a queue that implements SlmQueue\Queue\QueueInterface and provides in addition the following methods:

• release(JobInterface $job, array $options = array()): when a job fails, you can add the job again to the queue by releasing it, so that it can have another chance to be executed.
• bury(JobInterface $job, array $options = array()): when a job fails and that it has not been manually released, it is automatically buried.
• kick($max): when this method is called, it will move a maximum of $max buried jobs back to the queue.

A concrete class that implements this interface is included: SlmQueueBeanstalkd\Queue\BeanstalkdQueue and a factory is available to create the queue. Therefore, if you want to have a queue called "email", just add the following line in your module.config.php file:

return array(
    'slm_queue' => array(
        'queue_manager' => array(
            'factories' => array(
                'email' => 'SlmQueueBeanstalkd\Factory\BeanstalkdQueueFactory'
            )
        )
    )
);

This queue can therefore be pulled from the QueuePluginManager class.

Valid options are:

• priority: the lower the priority is, the sooner the job get popped from the queue (default to 1024)
• delay: the delay in seconds before a job become available to be popped (default to 0 - no delay -)
• ttr: in seconds, how much time a job can be reserved for (default to 60)

Example:

$queue->push($job, array(
    'priority' => 20,
    'delay'    => 23,
    'ttr'      => 50
));

Valid option is:

• timeout: by default, when we ask for a job, it will block until a job is found (possibly forever if new jobs never come). If you set a timeout (in seconds), it will return after the timeout is expired, even if no jobs were found

Valid options are:

• priority: the lower the priority is, the sooner the job get popped from the queue (default to 1024)
• delay: the delay in seconds before a job become available to be popped (default to 0 - no delay -)

Valid option is:

• priority: the lower the priority is, the sooner the job get kicked

Beanstalkd offers a nice bury/kick/release mechanism, so that jobs that fail can have a second chance to be executed. SlmQueueBeanstalkd provides a nice way to easily bury/release a job. In fact, you just need to throw either the SlmQueueBeanstalkd\Job\Exception\BuryableException or SlmQueueBeanstalkd\Job\Exception\ReleasableException in the execute method of your job:

use SlmQueue\Job\AbstractJob;
use SlmQueueBeanstalkd\Job\Exception;

class SimpleJob extends AbstractJob
{
    public function execute()
    {
        // Bury the job, with a priority of 10
        throw new Exception\BuryableException(array('priority' => 10));

        // Release the job, with a priority of 10 and delay of 5 seconds
        throw new Exception\ReleasableException(array('priority' => 10, 'delay' => 5));
    }
}

SlmQueueBeanstalkd provides a command-line tool that can be used to pop and execute jobs. You can type the following command within the public folder of your Zend Framework 2 application:

php index.php queue beanstalkd <queue> [--timeout=]

The queue is a mandatory parameter, while the timeout is an optional flag that specifies the duration in seconds for which the call will wait for a job to arrive in the queue before returning (because the script can wait forever if no job come).