Object-Oriented PHP for Drupal 8, 9, 10, and 11

PHP attributes are a native PHP language feature, introduced in PHP 8.0, that provide a way to add metadata to classes, methods, properties, and functions in PHP code.

In Drupal, this metadata is used by the plugin system to aid in the discovery and configuration of plugin instances. As a Drupal developer, it's important to understand how to recognize, read, and write PHP attributes, as you'll encounter them when working with plugins.

In this tutorial we'll look at:

• What PHP attributes are
• The use case for attributes in Drupal
• An overview of the attribute syntax

By the end of this tutorial, you should understand how attributes are used in Drupal and how to write them in your own code.

This reference document contains a detailed list of available properties for the #[ContentEntityType] attribute in Drupal 11. The current documentation in the Drupal 11 code base lists, but doesn't always describe, each of these properties. Or, in many cases, the property is an associative array where the nested key/value pairs are important, but what they should be isn't well documented. So we've created this helpful reference. Most of the properties listed here will also apply to #[ConfigEntityType] attributes. These properties define the metadata and behavior of custom entity types.

In this tutorial, we'll:

• Look at an example of how to use #[ContentEntityType] attributes.
• Provide a comprehensive list of available properties and a description of each.
• Show detailed examples of using nested array properties like handlers[].

By the end of this tutorial, you should be able to understand how and when to use any of the properties of a #[ContentEntityType] attribute in order to modify the behavior of a custom entity type.