WordPress REST API Tips

Why?

While developing our plugins we encounter the need of using the WordPress REST API more and more often, and we found that the new V2 API can be an enjoyable API to use.

If you ever used the wp.ajax JavaScript object or the WordPress wp_ajax_ PHP filters you should give a serious try to the new REST API since it covers all the flexibility you need.

From where?

We encourage you to read the full documentation of the V2 API to have the minimal understanding of this system.

The WordPress Codex also has a handbook about the REST API

The API Client

As a client(aka the entity which gets data from the API), you can always implement your own way of requesting data from API.

There are some recommendations based on the environment you want to use like:

Javascript

The wp-api script –– a Backbone collection of all endpoints supported in this API by default
There is also a npm client client
The old fashion jQuery.ajax(or maybe fetch if you feel modern) if you need a simply and very quick way of requesting a specific endpoint and process your response in a specific way

PHP

The first recommendation is the WordPress function wp_remote_post, learn this function well and make your own custom requests.
There is a PHP client example which you can use a starter.
Another PHP client example which has a full integration with the Oauth1

Custom endpoints

If you want to create your own custom routes, you need to make use of the rest_api_init action. The Handbook has an entire chapter about this.

The response callback

While creating your own callback, you need to be careful at returning value.

It may be tempting to use the wp_send_json_ since it is the standard way to end AJAX requests.But remember that this function ends in an exit statement so in this case, the API system will not have the chance to run any other actions after that.

A better way to respond in callback is the function rest_ensure_response

Authentication

For Admin dashboard features we recommend the use of the basic nonce authentication since it is simple to use.