Yes, this makes sense. I think you can implement as a system test. Harsh Vasava (Jira) <[email protected]> schrieb am Fr., 4. Sept. 2026, 19:01:
> > [ > https://urldefense.com/v3/__https://issues.apache.org/jira/browse/KAFKA-20971?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=18111633*comment-18111633__;Iw!!Ayb5sqE7!oYBboUbHdK6Opm0uk8ECeP0WDRf1g_Z9dmjdmmZQztVjZLKc6UOizt5dLq1h3kEcAiiPevITE71wzNPQpA$ > ] > > Harsh Vasava commented on KAFKA-20971: > -------------------------------------- > > That's helpful, thanks. On the negative case: the interesting part isn't > just that it fails, but _how_ it fails — the 4.4+ client sends a real > {{STREAMS_GROUP_HEARTBEAT}} to the old broker, which correctly rejects it > with {{INVALID_REQUEST}} ("Static membership is not yet supported"), and > the client then shuts itself down cleanly to {{ERROR}} state rather than > hanging or retrying indefinitely. > > That's genuine cross-version protocol behavior that a unit test can't > exercise (it needs an actual old-broker binary + real network round-trip), > so I think it's worth keeping as a regression test. I already have this > test written and verified passing against both 4.2.1 and 4.3.1 brokers — > happy to scope the PR down to just this test if that direction makes sense. > > > Add cross version system test for "streams" static group membership > > ------------------------------------------------------------------- > > > > Key: KAFKA-20971 > > URL: > https://urldefense.com/v3/__https://issues.apache.org/jira/browse/KAFKA-20971__;!!Ayb5sqE7!oYBboUbHdK6Opm0uk8ECeP0WDRf1g_Z9dmjdmmZQztVjZLKc6UOizt5dLq1h3kEcAiiPevITE701VCbrRg$ > > Project: Kafka > > Issue Type: Test > > Components: streams, system tests > > Affects Versions: 4.4.0 > > Reporter: Matthias J. Sax > > Assignee: Harsh Vasava > > Priority: Minor > > > > We added support for static group membership on the "streams" protocol. > This is a broker side fix, and thus Kafka Streams client 4.3 and 4.2 should > also be able to use static membership against a 4.4+ broker. But we do not > have a system test for this. > > We should also have a negative test, that a 4.4+ Kafka Streams client, > agains an older broker 4.3/4.2 get a clear error message that static > membership is not supported. > > > > -- > This message was sent by Atlassian Jira > (v8.20.10#820010) >
