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https://issues.apache.org/jira/browse/KAFKA-10357?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17174279#comment-17174279
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Bruno Cadonna commented on KAFKA-10357:
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I have a couple of questions regarding wild idea 1):
1) I guess you mean STARTING and not CREATED, don't you? There is no transition
from CREATED to PARTITION_REVOKED or PARTITION_ASSIGNED.
2) I suppose this check on the states of the stream threads is done in the
group leader. If a Streams client joined an existing group and a stream thread
of this newly added Streams client were elected as the group leader, then we
would have the situation where the stream thread is in STARTING but it would
not be the first-ever rebalance. Is this correct?
> Handle accidental deletion of repartition-topics as exceptional failure
> -----------------------------------------------------------------------
>
> Key: KAFKA-10357
> URL: https://issues.apache.org/jira/browse/KAFKA-10357
> Project: Kafka
> Issue Type: Improvement
> Components: streams
> Reporter: Guozhang Wang
> Assignee: Bruno Cadonna
> Priority: Major
>
> Repartition topics are both written by Stream's producer and read by Stream's
> consumer, so when they are accidentally deleted both clients may be notified.
> But in practice the consumer would react to it much quicker than producer
> since the latter has a delivery timeout expiration period (see
> https://issues.apache.org/jira/browse/KAFKA-10356). When consumer reacts to
> it, it will re-join the group since metadata changed and during the triggered
> rebalance it would auto-recreate the topic silently and continue, causing
> data lost silently.
> One idea, is to only create all repartition topics *once* in the first
> rebalance and not auto-create them any more in future rebalances, instead it
> would be treated similar as INCOMPLETE_SOURCE_TOPIC_METADATA error code
> (https://issues.apache.org/jira/browse/KAFKA-10355).
> The challenge part would be, how to determine if it is the first-ever
> rebalance, and there are several wild ideas I'd like to throw out here:
> 1) change the thread state transition diagram so that CREATED state would not
> transit to PARTITION_REVOKED but only to PARTITION_ASSIGNED, then in the
> assign function we can check if the state is still in CREATED and not RUNNING.
> 2) augment the subscriptionInfo to encode whether or not this is the first
> time ever rebalance.
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