1. 8.3.x core/lib/Drupal/Core/Entity/entity.api.php entity_api
  2. 8.0.x core/lib/Drupal/Core/Entity/entity.api.php entity_api
  3. 8.1.x core/lib/Drupal/Core/Entity/entity.api.php entity_api
  4. 8.2.x core/lib/Drupal/Core/Entity/entity.api.php entity_api
  5. 8.4.x core/lib/Drupal/Core/Entity/entity.api.php entity_api

Describes how to define and manipulate content and configuration entities.

Entities, in Drupal, are objects that are used for persistent storage of content and configuration information. See the Information types topic for an overview of the different types of information, and the Configuration API topic for more about the configuration API.

Each entity is an instance of a particular "entity type". Some content entity types have sub-types, which are known as "bundles", while for other entity types, there is only a single bundle. For example, the Node content entity type, which is used for the main content pages in Drupal, has bundles that are known as "content types", while the User content type, which is used for user accounts, has only one bundle.

The sections below have more information about entities and the Entity API; for more detailed information, see https://www.drupal.org/developing/api/entity.

Defining an entity type

Entity types are defined by modules, using Drupal's Plugin API (see the Plugin API topic for more information about plugins in general). Here are the steps to follow to define a new entity type:

  • Choose a unique machine name, or ID, for your entity type. This normally starts with (or is the same as) your module's machine name. It should be as short as possible, and may not exceed 32 characters.
  • Define an interface for your entity's get/set methods, usually extending either \Drupal\Core\Config\Entity\ConfigEntityInterface or \Drupal\Core\Entity\ContentEntityInterface.
  • Define a class for your entity, implementing your interface and extending either \Drupal\Core\Config\Entity\ConfigEntityBase or \Drupal\Core\Entity\ContentEntityBase, with annotation for @ConfigEntityType or @ContentEntityType in its documentation block.
  • The 'id' annotation gives the entity type ID, and the 'label' annotation gives the human-readable name of the entity type. If you are defining a content entity type that uses bundles, the 'bundle_label' annotation gives the human-readable name to use for a bundle of this entity type (for example, "Content type" for the Node entity).
  • The annotation will refer to several handler classes, which you will also need to define:

  • For content entities, the annotation will refer to a number of database tables and their fields. These annotation properties, such as 'base_table', 'data_table', 'entity_keys', etc., are documented on \Drupal\Core\Entity\EntityType.
  • For content entities that are displayed on their own pages, the annotation will refer to a 'uri_callback' function, which takes an object of the entity interface you have defined as its parameter, and returns routing information for the entity page; see node_uri() for an example. You will also need to add a corresponding route to your module's routing.yml file; see the entity.node.canonical route in node.routing.yml for an example, and see Entity routes below for some notes.
  • Optionally, instead of defining routes, routes can be auto generated by providing a route handler. See Entity routes. Otherwise, define routes and links for the various URLs associated with the entity. These go into the 'links' annotation, with the link type as the key, and the path of this link template as the value. The corresponding route requires the following route name: "entity.$entity_type_id.$link_template_type". See Entity routes below for some routing notes. Typical link types are:

    • canonical: Default link, either to view (if entities are viewed on their own pages) or edit the entity.
    • delete-form: Confirmation form to delete the entity.
    • edit-form: Editing form.
    • Other link types specific to your entity type can also be defined.
  • If your content entity is fieldable, provide 'field_ui_base_route' annotation, giving the name of the route that the Manage Fields, Manage Display, and Manage Form Display pages from the Field UI module will be attached to. This is usually the bundle settings edit page, or an entity type settings page if there are no bundles.
  • If your content entity has bundles, you will also need to define a second plugin to handle the bundles. This plugin is itself a configuration entity type, so follow the steps here to define it. The machine name ('id' annotation) of this configuration entity class goes into the 'bundle_entity_type' annotation on the entity type class. For example, for the Node entity, the bundle class is \Drupal\node\Entity\NodeType, whose machine name is 'node_type'. This is the annotation value for 'bundle_entity_type' on the \Drupal\node\Entity\Node class. Also, the bundle config entity type annotation must have a 'bundle_of' entry, giving the machine name of the entity type it is acting as a bundle for. These machine names are considered permanent, they may not be renamed.
  • Additional annotations can be seen on entity class examples such as \Drupal\node\Entity\Node (content) and \Drupal\user\Entity\Role (configuration). These annotations are documented on \Drupal\Core\Entity\EntityType.

Entity routes

Entity routes can be defined in *.routing.yml files, like any other route: see the Routing API topic for more information. Another option for entity routes is to use a route provider class, and reference it in the annotations on the entity class: see the end of this section for an example.

It's possible to use both a YAML file and a provider class for entity routes, at the same time. Avoid duplicating route names between the two: if a duplicate route name is found in both locations, the one in the YAML file takes precedence; regardless, such duplication can be confusing.

Here's an example YAML route specification, for the block configure form:

entity.block.edit_form:
  path: '/admin/structure/block/manage/{block}'
  defaults:
    _entity_form: 'block.default'
    _title: 'Configure block'
  requirements:
    _entity_access: 'block.update'

Some notes on this example:

  • path: The {block} in the path is a placeholder, which (for an entity) must always take the form of {machine_name_of_entity_type}. In the URL, the placeholder value will be the ID of an entity item. When the route is used, the entity system will load the corresponding entity item and pass it in as an object to the controller for the route.
  • defaults: For entity form routes, use _entity_form rather than the generic _controller or _form. The value is composed of the entity type machine name and a form handler type from the entity annotation (see Defining an entity type above more more on handlers and annotation). So, in this example, block.default refers to the 'default' form handler on the block entity type, whose annotation contains:
  handlers = {
    "form" = {
      "default" = "Drupal\block\BlockForm",
  

If instead of YAML you want to use a route provider class:

To register any route provider class, add lines like the following to your entity class annotation:

handlers = {
  "route_provider" = {
    "html" = "Drupal\Core\Entity\Routing\DefaultHtmlRouteProvider",

Defining a content entity bundle

For entity types that use bundles, such as Node (bundles are content types) and Taxonomy (bundles are vocabularies), modules and install profiles can define bundles by supplying default configuration in their config/install directories. (See the Configuration API topic for general information about configuration.)

There are several good examples of this in Drupal Core:

Loading, querying, and rendering entities

To load entities, use the entity storage manager, which is an object implementing \Drupal\Core\Entity\EntityStorageInterface that you can retrieve with:

$storage = \Drupal::entityManager()->getStorage('your_entity_type');
// Or if you have a $container variable:
$storage = $container->get('entity.manager')->getStorage('your_entity_type');

Here, 'your_entity_type' is the machine name of your entity type ('id' annotation on the entity class), and note that you should use dependency injection to retrieve this object if possible. See the Services and Dependency Injection topic for more about how to properly retrieve services.

To query to find entities to load, use an entity query, which is a object implementing \Drupal\Core\Entity\Query\QueryInterface that you can retrieve with:

// Simple query:
$query = \Drupal::entityQuery('your_entity_type');
// Or, if you have a $container variable:
$storage = $container->get('entity_type.manager')->getStorage('your_entity_type');
$query = $storage->getQuery();

If you need aggregation, there is an aggregate query available, which implements \Drupal\Core\Entity\Query\QueryAggregateInterface:

$query \Drupal::entityQueryAggregate('your_entity_type');
// Or:
$query = $storage->getAggregateQuery('your_entity_type');

In either case, you can then add conditions to your query, using methods like condition(), exists(), etc. on $query; add sorting, pager, and range if needed, and execute the query to return a list of entity IDs that match the query.

Here is an example, using the core File entity:

$fids = Drupal::entityQuery('file')
  ->condition('status', FILE_STATUS_PERMANENT, '<>')
  ->condition('changed', REQUEST_TIME - $age, '<')
  ->range(0, 100)
  ->execute();
$files = $storage->loadMultiple($fids);

The normal way of viewing entities is by using a route, as described in the sections above. If for some reason you need to render an entity in code in a particular view mode, you can use an entity view builder, which is an object implementing \Drupal\Core\Entity\EntityViewBuilderInterface that you can retrieve with:

$view_builder = \Drupal::entityManager()->getViewBuilder('your_entity_type');
// Or if you have a $container variable:
$view_builder = $container->get('entity.manager')->getViewBuilder('your_entity_type');

Then, to build and render the entity:

// You can omit the language ID, by default the current content language will
// be used. If no translation is available for the current language, fallback
// rules will be used.
$build = $view_builder->view($entity, 'view_mode_name', $language->getId());
// $build is a render array.
$rendered = drupal_render($build);

Access checking on entities

Entity types define their access permission scheme in their annotation. Access permissions can be quite complex, so you should not assume any particular permission scheme. Instead, once you have an entity object loaded, you can check for permission for a particular operation (such as 'view') at the entity or field level by calling:

$entity->access($operation);
$entity->nameOfField->access($operation);

The interface related to access checking in entities and fields is \Drupal\Core\Access\AccessibleInterface.

The default entity access control handler invokes two hooks while checking access on a single entity: hook_entity_access() is invoked first, and then hook_ENTITY_TYPE_access() (where ENTITY_TYPE is the machine name of the entity type). If no module returns a TRUE or FALSE value from either of these hooks, then the entity's default access checking takes place. For create operations (creating a new entity), the hooks that are invoked are hook_entity_create_access() and hook_ENTITY_TYPE_create_access() instead.

The Node entity type has a complex system for determining access, which developers can interact with. This is described in the Node access topic.

See also

Internationalization

Entity CRUD, editing, and view hooks

\Drupal\Core\Entity\EntityManagerInterface::getTranslationFromContext()

File

core/lib/Drupal/Core/Entity/entity.api.php, line 237
Hooks and documentation related to entities.

Functions

Namesort descending Location Description
hook_entity_access core/lib/Drupal/Core/Entity/entity.api.php Control entity operation access.
hook_entity_create_access core/lib/Drupal/Core/Entity/entity.api.php Control entity create access.
hook_ENTITY_TYPE_access core/lib/Drupal/Core/Entity/entity.api.php Control entity operation access for a specific entity type.
hook_ENTITY_TYPE_create_access core/lib/Drupal/Core/Entity/entity.api.php Control entity create access for a specific entity type.

Classes

Namesort descending Location Description
ConfigEntityBase core/lib/Drupal/Core/Config/Entity/ConfigEntityBase.php Defines a base configuration entity class.
ConfigEntityListBuilder core/lib/Drupal/Core/Config/Entity/ConfigEntityListBuilder.php Defines the default class to build a listing of configuration entities.
ConfigEntityStorage core/lib/Drupal/Core/Config/Entity/ConfigEntityStorage.php Defines the storage class for configuration entities.
ConfigEntityType core/lib/Drupal/Core/Entity/Annotation/ConfigEntityType.php Defines a config entity type annotation object.
ContentEntityBase core/lib/Drupal/Core/Entity/ContentEntityBase.php Implements Entity Field API specific enhancements to the Entity class.
ContentEntityType core/lib/Drupal/Core/Entity/Annotation/ContentEntityType.php Defines a content entity type annotation object.
ContentTranslationHandler core/modules/content_translation/src/ContentTranslationHandler.php Base class for content translation handlers.
EntityConfirmFormBase core/lib/Drupal/Core/Entity/EntityConfirmFormBase.php Provides a generic base class for an entity-based confirmation form.
EntityDeleteForm core/lib/Drupal/Core/Entity/EntityDeleteForm.php Provides a generic base class for an entity deletion form.
EntityForm core/lib/Drupal/Core/Entity/EntityForm.php Base class for entity forms.
EntityHandlerBase Deprecated core/lib/Drupal/Core/Entity/EntityHandlerBase.php Provides a base class for entity handlers.
EntityListBuilder core/lib/Drupal/Core/Entity/EntityListBuilder.php Defines a generic implementation to build a listing of entities.
EntityType core/lib/Drupal/Core/Entity/Annotation/EntityType.php Defines an Entity type annotation object.
EntityType core/lib/Drupal/Core/Entity/EntityType.php Provides an implementation of an entity type and its metadata.
EntityViewBuilder core/lib/Drupal/Core/Entity/EntityViewBuilder.php Base class for entity view builders.
RevisionableContentEntityBase core/lib/Drupal/Core/Entity/RevisionableContentEntityBase.php Provides a content entity with extended support for revisions.
SqlContentEntityStorage core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php A content entity database storage implementation.

Interfaces

Namesort descending Location Description
AccessibleInterface core/lib/Drupal/Core/Access/AccessibleInterface.php Interface for checking access.
ConfigEntityInterface core/lib/Drupal/Core/Config/Entity/ConfigEntityInterface.php Defines a common interface for configuration entities.
ContentEntityInterface core/lib/Drupal/Core/Entity/ContentEntityInterface.php Defines a common interface for all content entity objects.
EntityHandlerInterface core/lib/Drupal/Core/Entity/EntityHandlerInterface.php Defines an interface for entity handlers.
EntityInterface core/lib/Drupal/Core/Entity/EntityInterface.php Defines a common interface for all entity objects.
EntityStorageInterface core/lib/Drupal/Core/Entity/EntityStorageInterface.php Defines the interface for entity storage classes.
EntityViewBuilderInterface core/lib/Drupal/Core/Entity/EntityViewBuilderInterface.php Defines an interface for entity view builders.
FieldableEntityInterface core/lib/Drupal/Core/Entity/FieldableEntityInterface.php Interface for entities having fields.

Traits

Namesort descending Location Description
EntityDeleteFormTrait core/lib/Drupal/Core/Entity/EntityDeleteFormTrait.php Provides a trait for an entity deletion form.
RevisionLogEntityTrait core/lib/Drupal/Core/Entity/RevisionLogEntityTrait.php Provides a trait for accessing revision logging and ownership information.