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https://issues.apache.org/jira/browse/KAFKA-2350?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14637753#comment-14637753
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Jason Gustafson commented on KAFKA-2350:
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[~jkreps] This is a little unrelated to this jira, but one nice consequence of
moving group management into configuration is that it opens the door to using
subscribe(topic) as a shortcut to subscribing to all of a topic's partitions
for users who do not want to use group management (which does have a little
overhead). Currently the user would have to get all the partitions for that
topic and then subscribe to them individually. Not that bad, but a tad
annoying, especially if you have to poll for changes in the number of
partitions.
Anyway, I tend to agree with [~yasuhiro.matsuda] and [~gwenshap] that trying to
mix partition and topic subscriptions in order to do pausing seems problematic.
The explicit pause/unpause methods might not be as elegant, but I think they
are easier for users to understand and are much easier for us to implement.
> Add KafkaConsumer pause capability
> ----------------------------------
>
> Key: KAFKA-2350
> URL: https://issues.apache.org/jira/browse/KAFKA-2350
> Project: Kafka
> Issue Type: Improvement
> Reporter: Jason Gustafson
> Assignee: Jason Gustafson
>
> There are some use cases in stream processing where it is helpful to be able
> to pause consumption of a topic. For example, when joining two topics, you
> may need to delay processing of one topic while you wait for the consumer of
> the other topic to catch up. The new consumer currently doesn't provide a
> nice way to do this. If you skip poll() or if you unsubscribe, then a
> rebalance will be triggered and your partitions will be reassigned.
> One way to achieve this would be to add two new methods to KafkaConsumer:
> {code}
> void pause(String... topics);
> void unpause(String... topics);
> {code}
> When a topic is paused, a call to KafkaConsumer.poll will not initiate any
> new fetches for that topic. After it is unpaused, fetches will begin again.
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