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MEMBER_ID_REQUIRED(79, "Consumer needs to have a valid member id before actually entering group", MemeberIdRequiredException::new),

We shall also bump join group protocol version so that broker knows whether the consumer could safely handle this type of error. For example if we bump protocol version from m to m+1, all the request with version >= m+1 will be returned with MEMBER_ID_REQUIRED error, while version <= m will still be blindly accepted for backward compatibility.

Proposed Changes

When encountering MEMBER_ID_REQUIRED exception, the client will use the given member id in the join group response to retry the join, which is expected to be accepted by the broker if id matches. If we encounter UNKNOWN_MEMBER_ID exception with the second join attempt, client handling logic will be the same, which is reseting the generation and ask a new member id from broker by sending anonymous join group request.

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