Hi Whiskers. I've submitted a PR [1] to move the ack implementations to the common package.
The ack logic that responds to kafka messages to the controller can be used by other components in the downstream. However, because it's currently included in InvokerReactive, it's not available to other components, so I moved that logic to the common package. [1] https://github.com/apache/openwhisk/pull/4837 Any feedback is welcome. Thanks! KoenHee