Example: Plugin Types

Example of how to define a plugin type.

Our example defines a Sandwich plugin type. Sandwich's come in many flavors, each having their unique qualities, but also sharing things in common. Our Sandwich plugins will be very simple, each providing a unique description of themselves. In addition to the id property required by all plugin types, sandwich plugins have description, and calories properties.

Defining a new plugin type requires the following steps:

• Define an annotation class for your plugin type used to provide documentation about the meta-data needed by your plugin type.
• Define an interface for plugins of your new type to implement.
• Define a new plugin manager.
• Provide an optional base class that implements your plugin type's interface as a starting point for other plugin implementations.

Start at the class \Drupal\plugin_type_example\SandwichPluginManager, which defines our plugin manager. Our plugin manager is exposed to Drupal as a service in the plugin_type_example.services.yml file, and is used to glue our Drupal\plugin_type_example\SandwichInterface, and \Drupal\plugin_type_example\Annotation\Sandwich annotation definition together into a new plugin type.

We've also defined two implementations of our plugin type, \Drupal\plugin_type_example\Plugin\Sandwich\ExampleHamSandwich and \Drupal\plugin_type_example\Plugin\Sandwich\ExampleMeatballSandwich. Take a look at each. These plugins use annotated plugin discovery, and as such have an annotation block in the doc block for the class. Other than that, they implement the \Drupal\plugin_type_example\SandwichInterface, which is required, since we've set that interface for the plugin type in \Drupal\plugin_type_example\SandwichPluginManager::__construct.

In plugin_type_example_sandwich_info_alter() we'll demonstrate how you can alter a plugin definition using an alter hook.

To see the plugins in action visit /examples/plugin_type_example. The output is rendered in Drupal\plugin_type_example\Controller\PluginTypeExampleController::description(). Read through that method to see how to make use of plugins using the plugin.manager.sandwich service.

Parent topics

File

plugin_type_example/plugin_type_example.module, line 8

Demonstrates how to define a new plugin type.

Functions

Name	Location	Description
plugin_type_example_sandwich_info_alter	plugin_type_example/plugin_type_example.module	Implements hook_sandwich_info_alter().

Classes

Name	Location	Description
PluginTypeExampleTest	plugin_type_example/tests/src/Functional/PluginTypeExampleTest.php	Test the functionality of the Plugin Type Example module.