[
https://issues.apache.org/jira/browse/FLINK-8306?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16319816#comment-16319816
]
ASF GitHub Bot commented on FLINK-8306:
---------------------------------------
Github user tzulitai commented on the issue:
https://github.com/apache/flink/pull/5200
Regarding the race condition you mentioned:
hmm, I can't seem to exactly nail down the "and only first
`successfulCommits.inc()` can be omitted because of that" case you mentioned,
could you elaborate on that a bit more?
But yes, it seems like there certainly is a race condition here, and can
even cause an NPE on:
https://github.com/apache/flink/blob/master/flink-connectors/flink-connector-kafka-0.9/src/main/java/org/apache/flink/streaming/connectors/kafka/internal/KafkaConsumerThread.java#L496
Seems like the `nextOffsetsToCommit` and its callback instance should be
bundled as a single `AtomicReference` here ...
Would you like to open a PR for that? I wanted to ask because you
discovered it in the first place; if not I'll open a fix for it.
> FlinkKafkaConsumerBaseTest has invalid mocks on final methods
> -------------------------------------------------------------
>
> Key: FLINK-8306
> URL: https://issues.apache.org/jira/browse/FLINK-8306
> Project: Flink
> Issue Type: Bug
> Components: Kafka Connector, Tests
> Reporter: Tzu-Li (Gordon) Tai
> Assignee: Tzu-Li (Gordon) Tai
> Priority: Critical
> Fix For: 1.5.0, 1.4.1
>
>
> The {{FlinkKafkaConsumerBaseTest}} has invalid mocks on a final
> {{AbstractFetcher::commitInternalOffsetsToKafka(...)}} method. While an easy
> fix would be to simply make that method non-final, that is not ideal since it
> would be best that the method is left final to prevent overrides in
> subclasses.
> This suggests that offset committing functionality is too tightly coupled
> with the {{AbstractFetcher}}, making it hard to perform concise tests to
> verify offset committing.
> I suggest that we decouple record fetching and offset committing as separate
> services behind different interfaces. We should introduce a new interface,
> say {{KafkaOffsetCommitter}}, and test against that instead. Initially, we
> can simply let {{AbstractFetcher}} implement {{KafkaOffsetCommitter}}.
--
This message was sent by Atlassian JIRA
(v6.4.14#64029)
