How to use Batch API to do heavy processing in Drupal 8 & 9
The batch API in Drupal allows heavy and / or long processing to be carried out, without the risk of having an execution time exceeded on the part of its server.
in this article i want to do an example how to use the batch api.
So I have a route defined which calls the static "batchExample" method of my controller.
Function of who prepares the batch to be processed:
public function batchExample() {
$batch = array(
'title' => t('Import Data...'),
'operations' => [],
'init_message' => t('Commencing'),
'progress_message' => t('Processed @current out of @total.'),
'error_message' => t('An error occurred during processing'),
'finished' => 'import_data_finished',
);
for ($i = 0; $i < 100; $i++) {
$batch['operations'][] = ['import_data_test', [$i]];
}
batch_set($batch);
// Only needed if not inside a form _submit handler.
// Setting redirect in batch_process.
return batch_process('/admin/content');
}
here is an example if you want to use batch api inside form submit handler:
public function batchExample() {
$batch = array(
'title' => t('Import Data...'),
'operations' => [],
'init_message' => t('Commencing'),
'progress_message' => t('Processed @current out of @total.'),
'error_message' => t('An error occurred during processing'),
'finished' => 'import_data_finished',
);
for ($i = 0; $i < 100; $i++) {
$batch['operations'][] = ['import_data_test', [$i]];
}
batch_set($batch);
}
Here is the method called at the operations:
function import_data_test($nbre = 0, &$context)
{
$context['message'] = 'Import Data N° ' . $nbre;
$context['results'][] = $nbre;
usleep(50000);
}
Here is the method called at the end of the batch:
function import_data_finished($success, $results, $operations)
{
if ($success) {
$message = \Drupal::translation()->formatPlural(
count($results),
'One item processed.', '@count items processed.'
);
} else {
$message = t('Finished with an error.');
}
\Drupal::messenger()->addStatus($message);
}
screenshot for our example:
Nothing too complicated then, just add the import_data_test() and import_data_finished() methods in MODULENAME.module.
