Zilla MQTT authentication via REST endpoint

[wlaw868]

I have a use case where the MQTT server needs to authenticate users via a REST endpoint during the CONNECT phase and authorize their permission to subscribe to specific topics, also using the same REST endpoint. While I found examples using JWT, I haven't been able to set up external authentication similar to the webhook functionality provided by VerneMQ. Could someone assist me with creating a Zilla configuration file for this setup?