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Discussion thread: TBD
JIRA: here
https://issues.apache.org/jira/browse/KAFKA-9638
https://issues.apache.org/jira/browse/KAFKA-6520
Please keep the discussion on the mailing list rather than commenting on the wiki (wiki discussions get unwieldy fast).
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In order to be consistent, SHUTDOWN_CLIENT will leave the client state in ERROR instead of NOT_RUNNING. ERROR should be the state that exceptional failures leave the application in, not NOT_RUNNING.
Close() called on ERROR or PENDING_ERROR will be idempotent and not throw an exception but we will log a warning.
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