When metadata changes...

When metadata changes...

     what to do with cached docs?

1. Figure out what needs updating
2. Re-generate
3. Update stores

"...I'll just update right away!"

When metadata changes...

"...I'll just update right away!"

      meaning...

 When a Data Manager DID ANYTHING, they had to wait.

Drupal Queue API

Drupal Queue API

  1. Remember the relevant info

/**
 * Implements hook_entity_update().
 */
function mymodule_entity_update($entity, $entity_type) {

  ...

  // Remember relevant info.
  $item = array(
    'entity_type' => $entity_type,
    'entity' => $entity,
    'op' => 'update',
   
  );

  ...
}

Drupal Queue API

  2. Defer the work

...

// Create a queue to store items. 
// 'TRUE' means get a reliable queue type
//  - guarantees every item executes at least once
$queue = DrupalQueue::get('myWorkQueue', TRUE);

// Remember relevant info.
$item = array(
  'entity_type' => $entity_type,
    'entity' => $entity,
  'op' => 'update',
);

// Put an item into the queue.
$queue->createItem($item);

...

Drupal Queue API

  3. Ensure the work gets done

Drupal Queue API

  3. Ensure the work gets done:    DRUSH

// Get the queue. 
// 'TRUE' means get a reliable queue type.
$queue = DrupalQueue::get('myWorkQueue', TRUE);

// Iterate over the items.
while($item = $queue->claimItem()) {

  // Get the relevant information.
  $entity_type = $item['entity_type'];
  $entity = $item['entity'];
  $operation = $item['op'];

  $success = FALSE;
  // Do some work with the information you stored.
  // Specify if the task was successful $success = ???.

  // If successful, delete the item as it is no longer needed.
  if ($success) {
    $queue->deleteItem($item);
  }
}

Drupal Queue API

  3. Ensure the work gets done:    SUCCESS

// Iterate over the items.
while($item = $queue->claimItem()) {

...

  // If successful, delete the item as it is no longer needed.
  if ($success) {
    $queue->deleteItem($item);
  }
}