public function attemptUpdatingRowAsProcessing(Dunagan_ProcessQueue_Model_Task_Interface $taskObject)
{
$task_id = $taskObject->getId();
if (empty($task_id)) {
// $taskObject must be an existing/loaded object in order to lock it
return false;
}
// Status here can be PENDING or ERROR
$current_status = $taskObject->getStatus();
if (Dunagan_ProcessQueue_Model_Task::STATUS_PROCESSING == $current_status) {
// Assume another execution thread is actively processing this task
return false;
}
$current_gmt_datetime = Mage::getSingleton('core/date')->gmtDate();
// First, attempt to update the row based on id and status. If no rows are updated, another thread has already
// begun processing this row. Also we want to do this outside of any transactions so that we know other mysql
// connections will see that this row is already processing
$update_bind_array = array('status' => Dunagan_ProcessQueue_Model_Task::STATUS_PROCESSING, 'status_message' => null, 'last_executed_at' => $current_gmt_datetime);
$where_conditions_array = array('task_id=?' => $task_id, 'status=?' => $current_status, 'status<>?', Dunagan_ProcessQueue_Model_Task::STATUS_PROCESSING);
$rows_updated = $this->_getWriteAdapter()->update($this->getMainTable(), $update_bind_array, $where_conditions_array);
return $rows_updated;
}
