batch.queue.inc

<?php

/**
 * @file
 * Queue handlers used by the Batch API.
 *
 * These implementations:
 * - Ensure FIFO ordering.
 * - Allow an item to be repeatedly claimed until it is actually deleted (no
 * notion of lease time or 'expire' date), to allow multipass operations.
 */


/**
 * Defines a batch queue.
 *
 * Stale items from failed batches are cleaned from the {queue} table on cron
 * using the 'created' date.
 */
class BatchQueue  extends SystemQueue {
 
 /**
 * Overrides SystemQueue::claimItem().
 *
 * Unlike SystemQueue::claimItem(), this method provides a default lease
 * time of 0 (no expiration) instead of 30. This allows the item to be
 * claimed repeatedly until it is deleted.
 */
 public function claimItem($lease_time = 0) {
 $item = db_query_range ('SELECT data, item_id FROM {queue} q WHERE name = :name ORDER BY item_id ASC', 0, 1, array(
 ':name' => $this->name,
 ))
 ->fetchObject ();
 if ($item) {
 $item->data  = unserialize ($item->data );
 return $item;
 }
 return FALSE;
 }
 
 /**
 * Retrieves all remaining items in the queue.
 *
 * This is specific to Batch API and is not part of the DrupalQueueInterface.
 */
 public function getAllItems() {
 $result = array();
 $items = db_query ('SELECT data FROM {queue} q WHERE name = :name ORDER BY item_id ASC', array(
 ':name' => $this->name,
 ))
 ->fetchAll ();
 foreach ($items as $item) {
 $result[] = unserialize ($item->data );
 }
 return $result;
 }
}

/**
 * Defines a batch queue for non-progressive batches.
 */
class BatchMemoryQueue  extends MemoryQueue {
 
 /**
 * Overrides MemoryQueue::claimItem().
 *
 * Unlike MemoryQueue::claimItem(), this method provides a default lease
 * time of 0 (no expiration) instead of 30. This allows the item to be
 * claimed repeatedly until it is deleted.
 */
 public function claimItem($lease_time = 0) {
 if (!empty($this->queue)) {
 reset ($this->queue);
 return current ($this->queue);
 }
 return FALSE;
 }
 
 /**
 * Retrieves all remaining items in the queue.
 *
 * This is specific to Batch API and is not part of the DrupalQueueInterface.
 */
 public function getAllItems() {
 $result = array();
 foreach ($this->queue as $item) {
 $result[] = $item->data ;
 }
 return $result;
 }
}