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Kafka, mail # user - ways to exit the blocking iterator


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Re: ways to exit the blocking iterator
Joe Stein 2012-02-28, 14:08
Milind, if you are using the ZookeeperConsumerConnector then you can just
call shutdown() on it.

This will internally call sendShutdownToAllQueues which will pass the
"poison pill " of ZookeeperConsumerConnector.shutdownCommand to all queues.

On Tue, Feb 28, 2012 at 8:29 AM, Milind Parikh <[EMAIL PROTECTED]>wrote:

> I need to exit the blocking consumer iterator on certain conditions ; do
> some other processing and then resume the blocking iterartor. All of the
> work is dependent on the "other processing".
>
> Upon looking at the code, it seems that
>
> https://svn.apache.org/repos/asf/incubator/kafka/trunk/core/src/main/scala/kafka/consumer/ConsumerIterator.scala
> can take a shutdown command that will trigger the iterator to come out of
> the blocking state.
>
> Two Questions....
> (a) Is there some sample code  that will issue this shutdown command?
> (b) Is there any implication to the semantics of the queue that this
> iterator is blocking on ?
>
> (for example)
>
> Message_1
> Message_2
> SHUTDOWN
> Message_3
> Message_4
>
> should ideally deliver a unblock message to  the iterator and then continue
> delivering the messages to the queue ; and by implication; to the consumer
> iterator (of course, in 0.7, also recreating the MessageStream due to the
> timeout issue)
>
> Regards
> Milind
>

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Joe Stein
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