WordPress Rest API Boilerplate

rest-api-boilerplate.php

<?php
/**
 * Prefix Rest API
 *
 * @package Prefix Rest API
 * @since 1.0.0
 */

if ( ! class_exists( 'Prefix_Rest_API' ) ) :

	/**
	 * Prefix_Rest_API
	 *
	 * @since 1.0.0
	 */
	class Prefix_Rest_API {

		/**
		 * Instance
		 *
		 * @since 1.0.0
		 *
		 * @access private
		 * @var object Class object.
		 */
		private static $instance;

		/**
		 * Initiator
		 *
		 * @since 1.0.0
		 *
		 * @return object initialized object of class.
		 */
		public static function get_instance() {
			if ( ! isset( self::$instance ) ) {
				self::$instance = new self;
			}
			return self::$instance;
		}

		/**
		 * Constructor
		 *
		 * @since 1.0.0
		 */
		public function __construct() {
			add_action( 'rest_api_init', array( $this, 'api_actions' ) );
		}

		/**
		 * Register Route's
		 *
		 * @since 1.0.0
		 * @return void
		 */
		function api_actions() {
			register_rest_route(
				'prefix/v1', '/info',
				array(
					array(
						'methods'  => 'GET',
						'callback' => array( $this, 'info_callback' ),
					),
				)
			);
		}

		/**
		 * Retrieves all products.
		 *
		 * @since 1.0.0
		 * @access public
		 *
		 * @param WP_REST_Request $request Full details about the request.
		 * @return WP_Error|WP_REST_Response Response object on success, or WP_Error object on failure.
		 */
		public function info_callback( $request ) {
			return rest_ensure_response( 'Hello World' );
		}

	}

	/**
	 * Initialize class object with 'get_instance()' method
	 */
	Prefix_Rest_API::get_instance();

endif;