The plugin provides drag’n’drop file uploads and uses the wp rest api to upload the file.
This version adds a custom endpoint, has code for handling the upload and uploads the file to uploads/yyyy/mm without adding the file to the media library.  If you need to upload the file to the media library, see  DropzoneJS & WordPress REST API.

dropzonejs-wp-rest-api-custom-endpoint.php

dropzonejs-wp-rest-api-custom-endpoint.js

Installation

Save dropzonejs-wp-rest-api-custom-endpoint.php in wp-content/plugins/dropzonejs-wp-rest-api-custom-endpoint/
Save dropzonejs-wp-rest-api-custom-endpoint.js in wp-content/plugins/dropzonejs-wp-rest-api-custom-endpoint/js/

Use

After activating the plugin, add the [dropzonerest] shortcode to a post

Credits

https://www.dropzonejs.com/
https://github.com/WP-API/WP-API, I learned a lot reading the wp-api source

Copyright

The plugin is copyright Per Soderlind - per@soderlind.no

License

GPL, please feel free to modify the plugin as long as you make it GPL