[KAFKA-4349] Consumer group describe exception when group state is PreparingRebalance

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.10.2.0
• Assignee: Vahid Hashemian
• Reporter: Vahid Hashemian
• Created: 26/Oct/16 19:58
• Updated: 28/Oct/16 01:58
• Resolved: 28/Oct/16 01:58

Description

When the group state is PreparingRebalance the consumer group describe raises the following exception:

Error: Executing consumer group command failed due to Error reading field 'version': java.nio.BufferUnderflowException
org.apache.kafka.common.protocol.types.Schema.read(Schema.java:73)
org.apache.kafka.clients.consumer.internals.ConsumerProtocol.deserializeAssignment(ConsumerProtocol.java:106)
kafka.admin.AdminClient$$anonfun$1.apply(AdminClient.scala:155)
kafka.admin.AdminClient$$anonfun$1.apply(AdminClient.scala:154)
scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:244)
scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:244)
scala.collection.Iterator$class.foreach(Iterator.scala:727)
scala.collection.AbstractIterator.foreach(Iterator.scala:1157)
scala.collection.IterableLike$class.foreach(IterableLike.scala:72)
scala.collection.AbstractIterable.foreach(Iterable.scala:54)
scala.collection.TraversableLike$class.map(TraversableLike.scala:244)
scala.collection.AbstractTraversable.map(Traversable.scala:105)
kafka.admin.AdminClient.describeConsumerGroup(AdminClient.scala:154)
kafka.admin.ConsumerGroupCommand$KafkaConsumerGroupService.collectGroupAssignment(ConsumerGroupCommand.scala:391)
kafka.admin.ConsumerGroupCommand$ConsumerGroupService$class.describeGroup(ConsumerGroupCommand.scala:139)
kafka.admin.ConsumerGroupCommand$KafkaConsumerGroupService.describeGroup(ConsumerGroupCommand.scala:379)
kafka.admin.ConsumerGroupCommand$.main(ConsumerGroupCommand.scala:70)
kafka.admin.ConsumerGroupCommand.main(ConsumerGroupCommand.scala)

The exception is a side-effect of the fix for KAFKA-3144 that misses handling this edge case.

Issue Links

• is related to: KAFKA-3144 report members with no assigned partitions in ConsumerGroupCommand
• links to: GitHub Pull Request #2070