Hello

I’m possibly misunderstanding the complexity but what I normally do is that I inject things like modules dynamically dependent on the environment. For example, the code which uses the PubSub module to broadcast message to the topic, instead of the hardcoded PubSub module would have something like:

@pubsub_client Application.get_env(:naive, :pubsub_client)

and use it to broadcast:

@pubsub_client.broadcast(
  :ignore,
  topic,
  data
)

Option 2:

You could subscribe to the topic to figure out have you received the expected message back.

Option 3:

The broadcast function could be passed as an argument

I hope that helps somehow