Andr&eacute; Boekhorst

This plugin combines the two of the best WordPress plugins: <a href="https://wordpress.org/plugins/advanced-custom-fields/" title="Advanced Custom Fields" rel="ugc">Advanced Custom Fields</a> and <a href="https://wordpress.org/plugins/json-rest-api/" title="WP REST API" rel="ugc">WP REST API</a>.
This plugin is based on the work from<a href="https://github.com/PanManAms/WP-JSON-API-ACF" title="Panman on Github" rel="nofollow ugc">Panman on Github</a>. He was right when he said it would be better as plugin, but it would be even better if it would be available through the WordPress Plugin Repository.
An addition made to this plugin is that each ACF Field van be filtered throug the hook: JSON_META_ACFFIELDNAME (where ACFFIELDNAME depends on the fieldname you’ve added in the Advanced Custom Fields backend.)

WP REST API Custom Fields

The plugin is installed but nothing is in the output of API

JUst does not work

Shows Advanced Custom Field output to the WP REST API for posts, pages, taxonomies and users.

ksym04

Turn off JSON REST API on your website to anonymous users and prevent unauthorized requests from using the REST API to get information from your website.
Since the release of WordPress 4.0 came out, there have been a lot of hackers exploiting the vulnerabilities of the REST API. By installing this plugin, you will effectively prevent and disable the use of REST API from unauthorized users and protect the information on your website from being accessible. If someone tries to access the REST API on your site, the plugin will return an authentication error on the API endpoints, for any unauthorized users trying to access it.
While WordPress REST API vulnerability exploits continue this plugin effectively prevent and disable the used of REST API from accessing information from your website, this plugin return authentication error and disable all endpoints for any user not logged in on your website.
<h3>Translations</h3>
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<li>English (en_US)</li>
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Turn Off REST API

Prevents unauthorized requests from using the WP REST API.

WP REST API Custom Fields vs Turn Off REST API