node_scheduler.module

<?php

/**
 * Implements hook_cron().
 */
function node_scheduler_cron() {
  $queue = DrupalQueue::get('node_scheduler_queue');

  // Select all scheduled actions that were scheduled to happen by now
  $now = time();
  $query = db_select('node_scheduler', 'ns');
  $query->fields('ns')
    ->condition('scheduled_time', $now, '<')
    ->condition('queued_time', 0);
  $result = $query->execute();

  // Put each scheduled action in the queue to run
  while ($item = $result->fetch()) {
    $queue->createItem($item);

    // Set queued time on this item so that we know it was added to the queue
    $query = db_update('node_scheduler');
    $query->fields(array('queued_time' => $now))
      ->condition('nid', $item->nid)
      ->condition('schedule_key', $item->schedule_key)
      ->execute();
  }

  // Delete old rows from the table, if they were executed more than 30 days ago
  // TODO: Could use a variable to set how long to keep rows in the table
  $one_month_ago = $now - (3600 * 24 * 30);
  db_delete('node_scheduler')
    ->condition('executed_time', $one_month_ago, '<')
    ->condition('executed_time', 0, '>')
    ->execute();
}

/**
 * Implements hook_cron_queue_info().
 */
function node_scheduler_cron_queue_info() {
  $queues = array();
  $queues['node_scheduler_queue'] = array(
    //function to call for each item
    'worker callback' => 'node_scheduler_queue_callback',
    // seconds to spend working on the queue
    // TODO: This should ideally be a variable
    'time' => 10,
  );
  return $queues;
}

/**
 * Implements hook_hook_info().
 */
function node_scheduler_hook_info() {
  return array(
    'node_scheduler_action' => array(
      'group' => 'node_scheduler',
    ),
  );
}

/**
 * Callback function for queue node_scheduler_queue
 *
 * This function invokes the hook for other modules to run operations on this queue item.
 */
function node_scheduler_queue_callback($item) {
  try {
    module_invoke_all('node_scheduler_action', $item->nid, $item->schedule_key);

    // Set executed time on this item so that we know it was successfully run
    $now = time();
    $query = db_update('node_scheduler');
    $query->fields(array('executed_time' => $now))
      ->condition('nid', $item->nid)
      ->condition('schedule_key', $item->schedule_key)
      ->execute();
  }
  catch (Exception $e) {
    watchdog(
      'node_scheduler',
      'The scheduled action !schedule_key on the node !nid could not be executed.',
      array(
        '!nid' => $item->nid,
        '!schedule_key' => $item->schedule_key,
      ),
      WATCHDOG_ERROR
    );
  }
}


/**
 * Public function node_scheduler_clear_actions()
 *
 * Remove all unqueued, scheduled actions matching a schedule_key
 */
function node_scheduler_clear_actions($schedule_key, $keep_queued_actions = TRUE) {
  $query = db_delete('node_scheduler');
  $query->condition('schedule_key', $schedule_key);
  if ($keep_queued_actions) {
    $query->condition('queued_time', 0);
  }
  $query->execute();
}

/**
 * Public function node_scheduler_schedule_action()
 *
 * Schedule an action to fire on a node at some point in the future (requires cron)
 */
function node_scheduler_schedule_action($nid, $schedule_key, $scheduled_time, $reschedule = TRUE) {
  // If reschedule flag is set then remove any unqueued actions matching nid/key
  if ($reschedule) {
    node_scheduler_remove_action($nid, $schedule_key);
  }

  $now = time();
  if ($scheduled_time < $now) {
    $scheduled_time = $now;
  }

  // Insert this action into the node_scheduler table
  $query = db_insert('node_scheduler')
    ->fields(array(
      'nid' => $nid,
      'schedule_key' => $schedule_key,
      'scheduled_time' => $scheduled_time
    ))
    ->execute();
}

/**
 * Public function node_scheduler_remove_action()
 *
 * Remove any unqueued, scheduled actions possibly matching nid/schedule_key
 */
function node_scheduler_remove_action($nid = 'all', $schedule_key = 'all') {
  $query = db_delete('node_scheduler');
  if ($schedule_key <> 'all' ) {
    $query->condition('schedule_key', $schedule_key);
  }
  if ($nid <> 'all') {
    $query->condition('nid', $nid);
  }
  $query->condition('queued_time', 0);
  $query->execute();
}