[FLINK-16262] Class loader problem with FlinkKafkaProducer.Semantic.EXACTLY_ONCE and usrlib directory

• Type: Bug
• Status: Closed
• Priority: Blocker
• Resolution: Fixed
• Affects Version/s: 1.10.0
• Fix Version/s: 1.10.1, 1.11.0
• Component/s: Connectors / Kafka
• Labels: pull-request-available

Environment

openjdk:11-jre with a slightly modified Flink 1.10.0 build (nothing changed regarding Kafka and/or class loading).

• Assignee: Guowei Ma
• Reporter: Jürgen Kreileder
• Created: 24/Feb/20 18:38
• Updated: 02/Apr/20 10:37
• Resolved: 28/Mar/20 13:43

Description

We're using Docker images modeled after https://github.com/apache/flink/blob/master/flink-container/docker/Dockerfile (using Java 11)

When I try to switch a Kafka producer from AT_LEAST_ONCE to EXACTLY_ONCE, the taskmanager startup fails with:

2020-02-24 18:25:16.389 INFO  o.a.f.r.t.Task                           Create Case Fixer -> Sink: Findings local-krei04-kba-digitalweb-uc1 (1/1) (72f7764c6f6c614e5355562ed3d27209) switched from RUNNING to FAILED.
org.apache.kafka.common.config.ConfigException: Invalid value org.apache.kafka.common.serialization.ByteArraySerializer for configuration key.serializer: Class org.apache.kafka.common.serialization.ByteArraySerializer could not be found.
 at org.apache.kafka.common.config.ConfigDef.parseType(ConfigDef.java:718)
 at org.apache.kafka.common.config.ConfigDef.parseValue(ConfigDef.java:471)
 at org.apache.kafka.common.config.ConfigDef.parse(ConfigDef.java:464)
 at org.apache.kafka.common.config.AbstractConfig.<init>(AbstractConfig.java:62)
 at org.apache.kafka.common.config.AbstractConfig.<init>(AbstractConfig.java:75)
 at org.apache.kafka.clients.producer.ProducerConfig.<init>(ProducerConfig.java:396)
 at org.apache.kafka.clients.producer.KafkaProducer.<init>(KafkaProducer.java:326)
 at org.apache.kafka.clients.producer.KafkaProducer.<init>(KafkaProducer.java:298)
 at org.apache.flink.streaming.connectors.kafka.internal.FlinkKafkaInternalProducer.<init>(FlinkKafkaInternalProducer.java:76)
 at org.apache.flink.streaming.connectors.kafka.FlinkKafkaProducer.lambda$abortTransactions$2(FlinkKafkaProducer.java:1107)
 at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.accept(Unknown Source)
 at java.base/java.util.HashMap$KeySpliterator.forEachRemaining(Unknown Source)
 at java.base/java.util.stream.AbstractPipeline.copyInto(Unknown Source)
 at java.base/java.util.stream.ForEachOps$ForEachTask.compute(Unknown Source)
 at java.base/java.util.concurrent.CountedCompleter.exec(Unknown Source)
 at java.base/java.util.concurrent.ForkJoinTask.doExec(Unknown Source)
 at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(Unknown Source)
 at java.base/java.util.concurrent.ForkJoinPool.scan(Unknown Source)
 at java.base/java.util.concurrent.ForkJoinPool.runWorker(Unknown Source)
 at java.base/java.util.concurrent.ForkJoinWorkerThread.run(Unknown Source)

This looks like a class loading issue: If I copy our JAR to FLINK_LIB_DIR instead of FLINK_USR_LIB_DIR, everything works fine.

(AT_LEAST_ONCE producers works fine with the JAR in FLINK_USR_LIB_DIR)

 

Issue Links

• is caused by: FLINK-13498 Reduce Kafka producer startup time by aborting transactions in parallel
• links to: GitHub Pull Request #11247
• links to: GitHub Pull Request #11497