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  1. Kafka
  2. KAFKA-379

TopicCount.constructTopicCount isn't thread-safe

    Details

    • Type: Bug
    • Status: Closed
    • Priority: Major
    • Resolution: Fixed
    • Affects Version/s: 0.7, 0.8.0
    • Fix Version/s: 0.7, 0.8.0
    • Component/s: clients
    • Labels:

      Description

      TopicCount uses scala.util.parsing.json.JSON, which isn't thread-safe https://issues.scala-lang.org/browse/SI-4929

      If you have multiple consumers within the same JVM, and they all rebalance at the same time, you can get errors like the following:

      [...] kafka.consumer.TopicCount$.constructTopicCount:39] ERROR: error parsing consumer json string [...]
      java.lang.NullPointerException
      at scala.util.parsing.combinator.Parsers$NoSuccess.<init>(Parsers.scala:131)
      at scala.util.parsing.combinator.Parsers$Failure.<init>(Parsers.scala:158)
      at scala.util.parsing.combinator.Parsers$$anonfun$acceptIf$1.apply(Parsers.scala:489)
      ...
      at scala.util.parsing.combinator.Parsers$$anon$2.apply(Parsers.scala:742)
      at scala.util.parsing.json.JSON$.parseRaw(JSON.scala:71)
      at scala.util.parsing.json.JSON$.parseFull(JSON.scala:85)
      at kafka.consumer.TopicCount$.constructTopicCount(TopicCount.scala:32)
      at kafka.consumer.ZookeeperConsumerConnector$ZKRebalancerListener.kafka$consumer$ZookeeperConsumerConnector$ZKRebalancerListener$$getTopicCount(ZookeeperConsumerConnector.scala:422)
      at kafka.consumer.ZookeeperConsumerConnector$ZKRebalancerListener.kafka$consumer$ZookeeperConsumerConnector$ZKRebalancerListener$$rebalance(ZookeeperConsumerConnector.scala:460)
      at kafka.consumer.ZookeeperConsumerConnector$ZKRebalancerListener$$anonfun$syncedRebalance$1.apply$mcVI$sp(ZookeeperConsumerConnector.scala:437)
      at scala.collection.immutable.Range$ByOne$class.foreach$mVc$sp(Range.scala:282)
      at scala.collection.immutable.Range$$anon$2.foreach$mVc$sp(Range.scala:265)
      at kafka.consumer.ZookeeperConsumerConnector$ZKRebalancerListener.syncedRebalance(ZookeeperConsumerConnector.scala:433)
      at kafka.consumer.ZookeeperConsumerConnector$ZKRebalancerListener.handleChildChange(ZookeeperConsumerConnector.scala:375)
      at org.I0Itec.zkclient.ZkClient$7.run(ZkClient.java:568)
      at org.I0Itec.zkclient.ZkEventThread.run(ZkEventThread.java:71)

      I ran into this on 0.7.0, but the code in trunk appears to be vulnerable to the same issue.

        Attachments

        1. TopicCount.scala.diff
          2 kB
          Nick Howard
        2. kafka-379_0.8_v1.patch
          8 kB
          Jun Rao

          Activity

            People

            • Assignee:
              junrao Jun Rao
              Reporter:
              baroquebobcat Nick Howard
            • Votes:
              1 Vote for this issue
              Watchers:
              5 Start watching this issue

              Dates

              • Created:
                Updated:
                Resolved: