How do we set certain publish topics to be priority over other topics?

[russellgsystems]

We want the measurement data topic to have priority over other publish topics. We are using RabbitMQ as the MQTT broker. Maybe there is a way to set certain to higher priority in the RabbitMQ broker itself, but I haven't found it yet.

[francois-normandin]

There is no such priority queues defined in MQTT protocol. If RabbitMQ broker supports it, this is an added feature of that broker, and not part of the spec. You could extend the LV MQTT Server class to recognize certain messages as being priority messages, but I am unsure how deep you'd have to go.

Alternatively, you could setup a dual-port broker (two brokers running concurrently) where one port is prioritized for the execution in your aggregate application.

[russellgsystems]

Thanks @francois-normandin. I couldn't find a way to do with the RabbitMQ broker itself.