[Evidlo]

I remember one of the annoying things I found about actually using MQTT was that many clients didn't implement any sort of connect/disconnect callback and expected you to handle reconnection logic (e.g. exponential backoff) yourself. Also it didn't support RPC style requests for some reason.

Also since MQTT is TCP-based you can't natively speak the protocol from a webbrowser without the broker also listening on a websocket.

Ended up switching to WAMP-proto [0], which checked all my boxes and just did everything over websockets by default.

0: https://wamp-proto.org/

[pjbk]

MQTTv5 now has RPC. You can specify a response topic in the request message, and also add 'correlation' data to track the context of the call.