How to Expose REST APIs in Drupal 10: A Practical Guide

Specbee recently published a tutorial authored by Sahana N. titled "Exposing your API in Drupal - A brief tutorial", focusing on how to configure and expose RESTful APIs using Drupal 10. The post offers a concise overview of the architectural shift that started with Drupal 8, which introduced REST API capabilities in core, allowing developers to build modern applications that communicate over HTTP using GET, POST, PATCH, and DELETE methods.

The guide walks readers through the core and contributed Drupal modules essential for API exposure. These include HTTP Basic Authentication for secured access, RESTful Web Services to manage resource routes, Serialisation for handling request and response data, and REST UI, which simplifies endpoint configuration through the admin interface. Sahana also explains how the REST request-response pipeline works internally, detailing how data is deserialised, routed to resource plugins, processed, and finally serialised into a response.

The tutorial concludes with step-by-step instructions to set up REST endpoints, including enabling required modules and configuring endpoints via the admin UI or Postman. The post also notes that JSON:API, introduced in Drupal 8.5, is now the preferred method for exposing entity-based APIs, with JSON:API Extras offering customisation options. REST modules remain useful for operations like user authentication. This post serves as a practical entry point for Drupal developers seeking to expose or manage APIs in Drupal 10 projects.