Add operations (event handlers) to entities [#890220]

function hook_entity_info() {
  $return = array(
    'node_type' => array(
      'label' => t('Node type'),
      'base table' => 'node_type',
      'operations' => array(
        'delete' => array(
          'node' => 'delete',
        ),
      ),
    ),
  ),
}

This piece of code basically means entity API will automatically delete nodes related to a node type that is being deleted. It allows you to specify which operation needs to be performed on related entities if a certain operation is being applied to the defined entity. Valid operations are "load" and "update"/"delete" (currently not yet supported by the API).

Use cases:
- No more ghost nodes after a node type has been deleted.
- Nodes will be updated after the text format they use has been changed.

This idea came forward after a discussion between webchick, beeradb and me. Fago explained that this can also be done using hooks, which is true, but this extension to hook_entity_info() means less code in the end. Although this might not be a good enough argument to actually implement it, I do want to explore the possibilities such a new feature may offer us.

Comments

Comment #1

ctmattice1 CreditAttribution: ctmattice1 commented 22 August 2010 at 18:56

This would probably have to be the last part of the deletion process though, the comment module is looking for the type as well.

function comment_node_type_delete($info) {
  field_attach_delete_bundle('comment', 'comment_node_' . $info->type);
  $settings = array(
    'comment',
    'comment_default_mode',
    'comment_default_per_page',
    'comment_anonymous',
    'comment_subject_field',
    'comment_preview',
    'comment_form_location',
  );
  foreach ($settings as $setting) {
    variable_del($setting . '_' . $info->type);
  }

Either that or $info->type will have to be set in some variable before it's run so other entities will have it available for their part in the process.