Hello Walker, Thanks for the KIP! Overall it looks reasonable to me. Just a few minor comments for the wiki page itself:
1) Could you clarify the conditions when RUNNING / REBALANCING -> PENDING_ERROR will happen; and when PENDING_ERROR -> ERROR will happen. E.g. when I read "Streams will only reach ERROR state in the event of an exceptional failure in which the `StreamsUncaughtExceptionHandler` chose to either shutdown the application or the client." I thought the first transition would happen before the handler, and the second transition would happen immediately after the handler returns "shutdown client" or "shutdown application", until I read the last statement regarding "SHUTDOWN_CLIENT". 2) A compatibility issue: today it is possible that users would call Streams APIs like shutdown in the global state transition listener. And it's common to try shutting down the application automatically when transiting to ERROR (assuming it was not a terminating state). I think we could consider making this call a no-op and log a warning. 3) Could you link the following JIRAs in the "JIRA" field? https://issues.apache.org/jira/browse/KAFKA-10555 https://issues.apache.org/jira/browse/KAFKA-9638 https://issues.apache.org/jira/browse/KAFKA-6520 And maybe we can also left a comment on those tickets explaining what would happen to tackle the issues after this KIP. Guozhang On Tue, Dec 8, 2020 at 12:16 PM Walker Carlson <wcarl...@confluent.io> wrote: > Hello all, > > I'd like to propose KIP-696 to clarify the meaning of ERROR state in the > KafkaStreams Client State Machine. This will update the States to be > consistent with changes in KIP-671 and KIP-663. > > Here are the details: https://cwiki.apache.org/confluence/x/lCvZCQ > > Thanks, > Walker > -- -- Guozhang
