Customizing ZendQueue

Creating your own adapter

ZendQueue\Queue will accept any adapter that implements Zend\Queue\Adapter\AdapterAbstract. You can create your own adapter by extending one of the existing adapters, or the abstract class Zend\Queue\Adapter\AdapterAbstract. I suggest reviewing Zend\Queue\Adapter\Array as this adapter is the easiest to conceptualize.

class Custom_DbForUpdate extends Zend\Queue\Adapter\Db
{
    /**
     * @see code in tests/Zend/Queue/Custom/DbForUpdate.php
     *
     * Custom_DbForUpdate uses the SELECT ... FOR UPDATE to find it's rows.
     * this is more likely to produce the wanted rows than the existing code.
     *
     * However, not all databases have SELECT ... FOR UPDATE as a feature.
     *
     * Note: this was later converted to be an option for Zend\Queue\Adapter\Db
     *
     * This code still serves as a good example.
     */
}

$options = array(
    'name'          => 'queue1',
    'driverOptions' => array(
        'host'      => '127.0.0.1',
        'port'      => '3306',
        'username'  => 'queue',
        'password'  => 'queue',
        'dbname'    => 'queue',
        'type'      => 'pdo_mysql'
    )
);

$adapter = new Custom_DbForUpdate($options);
$queue = new Zend\Queue\Queue($adapter, $options);

You can also change the adapter on the fly as well.

$adapter = new MyCustom_Adapter($options);
$queue   = new Zend\Queue\Queue($options);
$queue->setAdapter($adapter);
echo "Adapter: ", get_class($queue->getAdapter()), "\n";

or

$options = array(
    'name'           => 'queue1',
    'namespace'      => 'Custom',
    'driverOptions'  => array(
        'host'       => '127.0.0.1',
        'port'       => '3306',
        'username'   => 'queue',
        'password'   => 'queue',
        'dbname'     => 'queue',
        'type'       => 'pdo_mysql'
    )
);
$queue = new Zend\Queue\Queue('DbForUpdate', $config); // loads Custom_DbForUpdate

Creating your own message class

ZendQueue\Queue will also accept your own message class. Our variables start with an underscore. For example:

class Zend\Queue\Message
{
    protected $_data = array();
}

You can extend the existing messaging class. See the example code in tests/Zend/Queue/Custom/Message.php.

Creating your own message iterator class

ZendQueue\Queue will also accept your own message iterator class. The message iterator class is used to return messages from Zend\Queue\Adapter\Abstract::receive(). Zend\Queue\Abstract::receive() should always return a container class like Zend\Queue\Message\Iterator, even if there is only one message.

See the example filename in tests/Zend/Queue/Custom/Messages.php.

Creating your own queue class

ZendQueue\Queue can also be overloaded easily.

See the example filename in tests/Zend/Queue/Custom/Queue.php.