[jira] [Updated] (KAFKA-3854) Subsequent regex subscription calls fail

["Vahid Hashemian (JIRA)" <ji...@apache.org>]

     [ https://issues.apache.org/jira/browse/KAFKA-3854?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Vahid Hashemian updated KAFKA-3854:
-----------------------------------
    Summary: Subsequent regex subscription calls fail  (was: Consecutive regex subscription calls fail)

> Subsequent regex subscription calls fail
> ----------------------------------------
>
>                 Key: KAFKA-3854
>                 URL: https://issues.apache.org/jira/browse/KAFKA-3854
>             Project: Kafka
>          Issue Type: Bug
>          Components: consumer
>            Reporter: Vahid Hashemian
>            Assignee: Vahid Hashemian
>
> There are a couple of issues with regex subscription in the new consumer:
> h6. Subsequent Subscriptions Fail
> When consecutive calls are made to new consumer's [regex subscription|https://github.com/apache/kafka/blob/trunk/clients/src/main/java/org/apache/kafka/clients/consumer/KafkaConsumer.java#L850], like below: 
> {code}
> consumer.subscribe(Pattern.compile("..."), listener);
> consumer.poll(0);
> consumer.subscribe(Pattern.compile("f.."), listener);
> consumer.poll(0);
> {code}
> the second call fails with the following error:
> {code}
> Exception in thread "main" java.lang.IllegalStateException: Subscription to topics, partitions and pattern are mutually exclusive
> 	at org.apache.kafka.clients.consumer.internals.SubscriptionState.subscribe(SubscriptionState.java:175)
> 	at org.apache.kafka.clients.consumer.KafkaConsumer.subscribe(KafkaConsumer.java:854)
> 	...
> {code}
> h6. Subsequent Subscriptions Fail to Trigger a Rebalance
> Even after the code is tweaked to get around the above issue, only the first call to regex subscription triggers the subscription's rebalance listener. The reason is the regex {{subscription}} / {{poll}} does not directly call {{changeSubscription(...)}} in which {{needsPartitionAssignment}} is set and causes a rebalance. This method is called only during the first regex {{subscription}} / {{poll}} when coordinator is unknown and [a {{client.poll}} call|https://github.com/apache/kafka/blob/trunk/clients/src/main/java/org/apache/kafka/clients/consumer/internals/AbstractCoordinator.java#L179] is made which eventually leads to [a {{changeSubscription}} call|https://github.com/apache/kafka/blob/trunk/clients/src/main/java/org/apache/kafka/clients/consumer/internals/ConsumerCoordinator.java#L161]. The subsequent call does not reach this point because the coordinator is already known.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)