Status

Current state:  DraftDiscussion

Discussion thread:  here https://lists.apache.org/thread/7xn8bd6obobnr1j284d13r993cb4nlt8

Vote thread:  here

JIRA: https://issues.apache.org/jira/browse/KAFKA-20402

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• A list of fully qualified class names implementing ConsumerGroupRebalanceListener.
• Classes are instantiated and configured by the broker at startup.
• Empty value means callback feature is disabled

Note:  Dynamic updatesDynamic updates are not planed in this scope out for now so that we can keep the KIP small, low-risk, and validate real usage first.

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Refer to the PR example:

Note:  Cover all non-classic consume group due to the classic consume group will be deprecated soon.

Compatibility, Deprecation, and Migration Plan 

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