ahmedimraan

This plugin adds Custom Fields to WP REST API JSON output. Works with Advanced Custom Fields. 
Its as simple as Installing and Activating, once activated you can see an object named metadata.

WP REST API POST/ PAGE CUSTOM FIELDS

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

Frankie Jarrett

Did you find this plugin helpful? Please consider <a href="https://wordpress.org/support/view/plugin-reviews/json-rest-api-force-ssl" rel="ugc">leaving a 5-star review</a>.
Note: This plugin requires the <a href="https://wordpress.org/plugins/json-rest-api/" rel="ugc">WP REST API (WP API)</a> plugin.
For site owners who want the WP REST API served over SSL always and forever.
All HTTP requests to the WP REST API will be 301 redirected to their HTTPS equivalent.
Also, don’t use this plugin unless you have an SSL certificate as your endpoints will break! 🙂
Development of this plugin is done <a href="https://github.com/fjarrett/json-rest-api-force-ssl" rel="nofollow ugc">on GitHub</a>. Pull requests welcome. Please see <a href="https://github.com/fjarrett/json-rest-api-force-ssl/issues" rel="nofollow ugc">issues reported</a> there before going to the plugin forum.

WP REST API Force SSL

Force WP REST API endpoints to only be served over HTTPS.

WP REST API POST/ PAGE CUSTOM FIELDS vs WP REST API Force SSL