/**
* Get messages in the queue
*
* @param integer $maxMessages Maximum number of messages to return
* @param integer $timeout Visibility timeout for these messages
* @param Zend_Queue $queue
* @return Zend_Queue_Message_Iterator
* @throws Zend_Queue_Exception - database error
*/
public function receive($maxMessages = null, $timeout = null, Zend_Queue $queue = null)
{
if ($maxMessages === null) {
$maxMessages = 1;
}
if ($timeout === null) {
$timeout = self::RECEIVE_TIMEOUT_DEFAULT;
}
if ($queue === null) {
$queue = $this->_queue;
}
$msgs = array();
$info = $this->_messageTable->info();
$microtime = microtime(true);
// cache microtime
$db = $this->_messageTable->getAdapter();
// start transaction handling
try {
if ($maxMessages > 0) {
// ZF-7666 LIMIT 0 clause not included.
$db->beginTransaction();
$query = $db->select();
if ($this->_options['options'][Zend_Db_Select::FOR_UPDATE]) {
// turn on forUpdate
$query->forUpdate();
}
$query->from($info['name'], array('*'))->where('queue_id=?', $this->getQueueId($queue->getName()))->where('handle IS NULL OR timeout+' . (int) $timeout . ' < ' . (int) $microtime)->limit($maxMessages);
foreach ($db->fetchAll($query) as $data) {
// setup our changes to the message
$data['handle'] = md5(uniqid(rand(), true));
$update = array('handle' => $data['handle'], 'timeout' => $microtime);
// update the database
$where = array();
$where[] = $db->quoteInto('message_id=?', $data['message_id']);
$where[] = 'handle IS NULL OR timeout+' . (int) $timeout . ' < ' . (int) $microtime;
$count = $db->update($info['name'], $update, $where);
// we check count to make sure no other thread has gotten
// the rows after our select, but before our update.
if ($count > 0) {
$msgs[] = $data;
}
}
$db->commit();
}
} catch (Exception $e) {
$db->rollBack();
// require_once 'Zend/Queue/Exception.php';
throw new Zend_Queue_Exception($e->getMessage(), $e->getCode(), $e);
}
$options = array('queue' => $queue, 'data' => $msgs, 'messageClass' => $queue->getMessageClass());
$classname = $queue->getMessageSetClass();
if (!class_exists($classname)) {
// require_once 'Zend/Loader.php';
Zend_Loader::loadClass($classname);
}
return new $classname($options);
}
/**
* Returns the length of the queue
*
* @return integer
*/
public function count()
{
$info = $this->_message->info();
$db = $this->_message->getAdapter();
$query = $db->select();
$query->from($info['name'], array(new Zend_Db_Expr('COUNT(*)')));
$query->where('queue_id=?', $this->getActiveQueue());
return $db->fetchOne($query);
}
