Like many other modules in Drupal, the RESTful Web Services module (see Chapter 7) can be extended with additional resource plug-ins that add new resources to the Drupal core REST API. Because the RESTful Web Services module is part of Drupal core, and because we should not modify Drupal core code under any circumstances, we can add resource plug-ins via a custom module.
For Drupal developers familiar with PHP, the process of creating a custom module, detailed in the first section, will be familiar and can be safely skipped in favor of the subsequent section. For those who are interested ...
