WordPress Create custom REST endpoint

WordPress, as a powerful content management system (CMS), allows developers to create custom REST endpoints. These endpoints enable communication between external applications and your WordPress site, making it possible to retrieve or manipulate data programmatically. WordPress gives various functions to work on REST API. Let's take a look at how you can easily create your custom endpoint.

In this article, we will see how to create a custom REST endpoint in WordPress. WordPress is not only used for blogging and simple site platforms. Now it's used for large-scale enterprise projects and even a headless CMS. So if you are using WordPress as a headless CMS, you must know how to work with the REST APIs.

We will use a rest_api_init action hook, and register_rest_route() inbuild function to create our custom endpoint.

Steps to Create a custom REST endpoint

You need to add this code to the theme's functions.php file.

Step 1: Create a function that registers the REST route with the register_rest_route() function.

<?php
function create_custon_endpoint(){
    register_rest_route(
        'wp/v2',
        '/custom-ep',
        array(
            'methods' => 'GET',
            'callback' => 'get_response',
        )
    );
}
?>

This function's first parameter is namespace 'wp/v2', the second parameter is endpoint name '/custom-ep' and the third parameter is an array where you can add methods like GET, POST, DELETE, etc., and a callback function. You can customize these values according to your need.

For more details, you can check the document.

Step 2: Create callback function get_response().

<?php
function get_response() {
    // Your code...
    return 'This is your data!';
}
?>

In this function, you can do whatever you want to add to your endpoint.

Step 3: Add action hook rest_api_init which will run our function create_custon_endpoint on initialization of REST API on WordPress.

<?php
add_action( 'rest_api_init', 'create_custon_endpoint');
?>

Complete Code: Below given the whole steps in one frame.

/* Create Custom Endpoint */
add_action( 'rest_api_init', 'create_custon_endpoint' );

function create_custon_endpoint(){
    register_rest_route(
        'wp/v2',
        '/custom-ep',
        array(
            'methods' => 'GET',
            'callback' => 'get_response',
        )
    );
}

function get_response() {
    // your code
    return 'This is your data!';
}

Output: