Does Drupal 8 entities have any events I can listen to?

Question

I know we can use hook_entity_update() hook to do something when an entity is updated. But is there an event to listen for node updates/deletes, or other entities such for that matter?

Answer 1

You can't listen to an event. You can either use a hook or implement a method like postSave() in your custom entity.

Here is the order of hooks and other events that happen during an entity save:

• Entity::preSave() is called on entity objects, and FieldItemListInterface::preSave() on field objects.
• hook_ENTITY_TYPE_presave()
• hook_entity_presave()
• Entity is saved to storage.
• Entity::postSave() is called on the entity object.
• hook_ENTITY_TYPE_insert() (new) or hook_ENTITY_TYPE_update() (update)
• hook_entity_insert() (new) or hook_entity_update() (update)

Answer 2

Ideally you would listen for entity related events but these aren't ready yet. See "Add events for matching entity hooks".

For now, if you're wanting to stay away from hooks, you can use a contrib module: Hook Event Dispatcher

Answer 3

A node is an entity type, so hook_ENTITY_TYPE_update(.. is the same as hook_node_update(..,

function hook_node_update(Drupal\Core\Entity\EntityInterface $entity) {
    //$entity->bundle()  - 'article' 'page'
}

or

function hook_customentity_update(Drupal\Core\Entity\EntityInterface $entity{
    //$entity->bundle()  - 'awesome_entity_bundle'
}

https://api.drupal.org/api/drupal/core!lib!Drupal!Core!Entity!entity.api.php/function/hook_ENTITY_TYPE_update/8.2.x