function farm_constraint_restws_request_alter in farmOS 7

Implements hook_restws_request_alter().

File

modules/farm/farm_constraint/farm_constraint.module, line 321

Farm constraint module.

Code

function farm_constraint_restws_request_alter(array &$request) {

  // Prevent deletion of entities that are referenced by other entities.
  // This works by altering the "operation" in the request object that is built
  // in restws_handle_request() before the access check is called. We replace
  // the "delete" operation with "noop" so that the access check fails.
  // This is a heavy-handed approach, and doesn't provide more nuanced options
  // for dealing with referenced data, but it works to stop the deletion from
  // occurring.

  /**
   * @todo
   * This is a very hacky way to do this, and doesn't provide any feedback to
   * the API user as to why their request fails.
   */

  // If an operation, resource, and ID are not available, bail.
  if (empty($request['op']) || empty($request['resource']) || empty($request['id'])) {
    return;
  }

  // We only care about delete operations.
  if ($request['op'] != 'delete') {
    return;
  }

  // Get the entity type.
  $type = $request['resource']
    ->resource();

  // Get the entity ID.
  $id = $request['id'];

  // Get the entity.
  $entity = $request['resource']
    ->read($id);

  // If the entity doesn't exist it cannot have constraints.
  if (empty($entity)) {
    return;
  }

  // Get the entity bundle.
  list($entity_id, $revision_id, $bundle) = entity_extract_ids($type, $entity);

  // If constraints exist on the entity, change the operation to 'noop' so the
  // access check in restws_handle_request() fails.
  if (farm_constraint_exists($type, $bundle, $id)) {
    $request['op'] = 'noop';
  }
}