Consuming multiple topics while using States

[markuspinter]

Is your feature request related to a problem? Please describe.
I would like to build an application that consumes from two different topics.
It's kind of a syncing problem:
I have one producer early on in the pipeline that creates a "Batch" message to a topic which includes
a batch start and end time together with a batch id.
When the pipeline is processed (mainly data sanitization) the last application produces another message to another topic
which indicates "batch processed" (including the batch id).

Now I would like to store the Batch info into a state and do some processing when this "batch processed" event arrives in the other topic.

This essentially means that I have to use a Consumer rather the data_frame since I need to subscribe to multiple topics.

However I can't find an easy way with quixstreams of using States without a DataFrame.
Do you have a clean solution to this problem? I tried to reuse code from the _as_stateful() function from the Application class, but this is quite cumbersume due to the process_context that is required.

Is this an anti pattern? I'm pretty new to kafka streams and I'm learning along the way.

Thanks for the help!

[tim-quix]

Heya @markuspinter !

QuixStreams 3.0 was just released and it allows you to consume from multiple topics at once with a StreamingDataFrame, so take a look and let us know if this solves your issue or not, as it sounds like it might!