Module Development

Using Entity Metadata Wrappers for Drupal 7

This page is archived

We're keeping this page up as a courtesy to folks who may need to refer to old instructions. We don't plan to update this page.

Alternate resources

Sprout Video

If you've done any module development, you're probably familiar with hook_node_view and Drupal's arrays of doom. In this lesson we'll show you how to get easier access to the same information using entity metadata wrappers. We will use the entity_metadata_wrapper function to retrieve a new EntityMetaDataWrapper object that provides an interface for easily accessing an entities property and field values. We'll use the getPropertyInfo method to expose information about individual properties, and the getIterator method to access fields that contain multiple values, such as tags. You'll see that by using meta data wrappers you can also access properties on referenced entities, such as the email address of the author of a node, without having to load that information independently.

Metadata wrappers also provide a consistent way to access properties common to all entities. For example, every entity in Drupal has a unique ID property or a human readable label, but these properties often have different names. User name vs. node title. Metadata wrappers allow you to access this information in a consistent way.

Additional resources

Entity metadata wrappers