class ComputingQueue in Drupal Computing 7.2

This file provides Queue support, an extra layer to handle computing records. The only benefit here is to provide an interface for Queue, perhaps people don't need it.

Hierarchy

• class \ComputingQueue implements DrupalReliableQueueInterface

File

./computing.queue.inc, line 8

class ComputingQueue implements DrupalReliableQueueInterface {
  protected $app_name;

  // singleton design pattern.
  private function __construct($app_name) {

    // we don't validate $app_name against "computing_application" entity.
    $this->app_name = $app_name;
  }

  /**
   * Factory method.
   * @param $app_name
   * @return object
   */
  public static function get($app_name) {
    static $queues;
    if (!isset($queues[$app_name])) {
      $object = new ComputingQueue($app_name);
      $queues[$app_name] = $object;
    }
    return $queues[$app_name];
  }

  ///////////////////////////// below are methods defined in DrupalReliableQueueInterface
  public function createItem($data) {
    if (is_object($data)) {
      $data = (array) $data;
    }
    $options = array_diff_key($data, array_flip(array(
      'application',
      'command',
      'label',
      'input',
    )));
    return (bool) computing_create($data['application'], $data['command'], $data['label'], $data['input'], $options);
  }
  public function numberOfItems() {
    return db_query("SELECT COUNT(id) FROM {computing_record} WHERE application = :name AND status = 'RDY'", array(
      ':name' => $this->app_name,
    ))
      ->fetchField();
  }
  public function claimItem($lease_time = 3600) {

    //$lease_time: not used.
    return computing_claim($this->app_name);
  }
  public function deleteItem($item) {

    // we'll not physically delete the item, but just mark the item as "ABD".
    if (!is_object($item)) {
      $item = (object) $item;
    }

    // this is to follow the definition in the interface.
    if (computing_update_field($item->id, 'status', 'ABD')) {
      return computing_load($item->id);
    }
    else {
      return FALSE;
    }
  }
  public function releaseItem($item) {
    if (!is_object($item)) {
      $item = (object) $item;
    }
    return computing_release($item->id);
  }
  public function createQueue() {

    // nothing to be done here as the 'computing' table/entity_type is created in installation.
  }
  public function deleteQueue() {

    // we won't delete any data here. keep everything for archival purpose.
  }

}

Members

Name	Modifiers	Type	Description	Overrides
ComputingQueue::$app_name	protected	property
ComputingQueue::claimItem	public	function	Claim an item in the queue for processing. Overrides DrupalQueueInterface::claimItem
ComputingQueue::createItem	public	function	Add a queue item and store it directly to the queue. Overrides DrupalQueueInterface::createItem
ComputingQueue::createQueue	public	function	Create a queue. Overrides DrupalQueueInterface::createQueue
ComputingQueue::deleteItem	public	function	Delete a finished item from the queue. Overrides DrupalQueueInterface::deleteItem
ComputingQueue::deleteQueue	public	function	Delete a queue and every item in the queue. Overrides DrupalQueueInterface::deleteQueue
ComputingQueue::get	public static	function	Factory method.
ComputingQueue::numberOfItems	public	function	Retrieve the number of items in the queue. Overrides DrupalQueueInterface::numberOfItems
ComputingQueue::releaseItem	public	function	Release an item that the worker could not process, so another worker can come in and process it before the timeout expires. Overrides DrupalQueueInterface::releaseItem
ComputingQueue::__construct	private	function