Framework
The Zend_Queue is a proxy that hides the details
of the queue services. The queue services are represented by
Zend_Queue_Adapter_<service>. For example,
Zend_Queue_Adapter_Db is a queue that will use
database tables to store and retrieve messages.
Below is an example for using database tables for a queuing system:
'queue1',
'driverOptions' => array(
'host' => '127.0.0.1',
'port' => '3306',
'username' => 'queue',
'password' => 'queue',
'dbname' => 'queue',
'type' => 'pdo_mysql'
)
);
// Create a database queue.
// Zend_Queue will prepend Zend_Queue_Adapter_ to 'Db' for the class name.
$queue = new Zend_Queue('Db', $options);
]]>
The Zend_Queue constructor will create a
Zend_Queue_Adapter_Db and initialize the adapter
with the configuration settings.
The accepted configuration settings for each adapter are provided
in the adapter notes.
Zend_Queue returns messages using the class
Zend_Queue_Message_Iterator, which is an
implementation of SPL Iterator and
Countable.
Zend_Queue_Message_Iterator contains an array of
Zend_Queue_Message objects.
receive(5);
foreach ($messages as $i => $message) {
echo "$i) Message => ", $message->body, "\n";
}
]]>
Any exceptions thrown are of class
Zend_Queue_Exception.
IntroductionZend_Queue is a proxy class that represents
an adapter.
The send(),
count($queue), and
receive() methods are employed by each
adapter to interact with queues.
The createQueue(),
deleteQueue() methods are used to manage
queues.
Commonality among adapters
The queue services supported by Zend_Queue do
not all support the same functions. For example,
Zend_Queue_Adapter_Array,
Zend_Queue_Adapter_Db, support all functions,
while Zend_Queue_Adapter_Activemq does not
support queue listing, queue deletion, or counting of messages.
You can determine what functions are supported by using
Zend_Queue::isSupported() or
Zend_Queue::getCapabilities().
createQueue() - create a queue
deleteQueue() - delete a queue
send() - send a message
send() is not available in all adapters; the
Zend_Queue_Adapter_Null does not
support send().
receive() - receive messages
receive() is not available in all adapters;
the Zend_Queue_Adapter_Null does not
support receive().
deleteMessage() - delete a
message
count() - count the number of
messages in a queue
isExists() - checks the existence
of a queue
receive() methods are employed by each
adapter to interact with queues.
The createQueue() and
deleteQueue() methods are used to manage
queues.