function batch_example_op_2 in Examples for Developers 7

Same name and namespace in other branches

1. 8 batch_example/batch_example.module \batch_example_op_2()
2. 6 batch_example/batch_example.module \batch_example_op_2()
3. 3.x modules/batch_example/batch_example.module \batch_example_op_2()

Batch operation for batch 2 : load all nodes, 5 by five.

After each group of 5 control is returned to the batch API for later continuation.

Related topics

1 string reference to 'batch_example_op_2'

batch_example_batch_2 in batch_example/batch_example.module

Batch 2 : Prepare a batch definition that will load all nodes 20 times.

File

batch_example/batch_example.module, line 208

Outlines how a module can use the Batch API.

Code

function batch_example_op_2($operation_details, &$context) {

  // Use the $context['sandbox'] at your convenience to store the
  // information needed to track progression between successive calls.
  if (empty($context['sandbox'])) {
    $context['sandbox'] = array();
    $context['sandbox']['progress'] = 0;
    $context['sandbox']['current_node'] = 0;

    // Save node count for the termination message.
    $context['sandbox']['max'] = db_query('SELECT COUNT(DISTINCT nid) FROM {node}')
      ->fetchField();
  }

  // Process nodes by groups of 5 (arbitrary value).
  // When a group of five is processed, the batch update engine determines
  // whether it should continue processing in the same request or provide
  // progress feedback to the user and wait for the next request.
  // That way even though we're already processing at the operation level
  // the operation itself is interruptible.
  $limit = 5;

  // Retrieve the next group of nids.
  $result = db_select('node', 'n')
    ->fields('n', array(
    'nid',
  ))
    ->orderBy('n.nid', 'ASC')
    ->where('n.nid > :nid', array(
    ':nid' => $context['sandbox']['current_node'],
  ))
    ->extend('PagerDefault')
    ->limit($limit)
    ->execute();
  foreach ($result as $row) {

    // Here we actually perform our dummy 'processing' on the current node.
    $node = node_load($row->nid, NULL, TRUE);

    // Store some results for post-processing in the 'finished' callback.
    // The contents of 'results' will be available as $results in the
    // 'finished' function (in this example, batch_example_finished()).
    $context['results'][] = $node->nid . ' : ' . check_plain($node->title) . ' ' . $operation_details;

    // Update our progress information.
    $context['sandbox']['progress']++;
    $context['sandbox']['current_node'] = $node->nid;
    $context['message'] = check_plain($node->title);
  }

  // Inform the batch engine that we are not finished,
  // and provide an estimation of the completion level we reached.
  if ($context['sandbox']['progress'] != $context['sandbox']['max']) {
    $context['finished'] = $context['sandbox']['progress'] >= $context['sandbox']['max'];
  }
  _batch_example_update_http_requests();
}