Unable to unsubscribe from multiple topics at once

[ctron]

Describe the feature

Currently there is an unsubscribe method, which only allows to unsubscribe from a single topic. However, with MQTT you can unsubscribe from multiple topic filters at the same time.

Use cases

Unsubscribe from multiple topics, in a single message.

[chenzhiguo]

Yeah, MQTT topic filters are a very important feature, look at the source implementation, it doesn't seem to do this specifically, right?

[tsegismont]

@ctron would you like to contribute?

[ctron]

I could draft up a PR. However I am not sure I can find the time to follow up on this to get it merged. I think this should come from the project.