运行 Spark 示例：ClassNotFoundException: org.apache.kafka.common.serialization.StringDeserializer

Question

I'm new to spark, and yet to write my first spark application and still investigating whether that would be a good fit for our purpose. Currently just trying to run the sample example that come with spark that access kafka

I tried to run kafka examples coming out of the box using two ways without success with same error.

1. from spark using helm/kubernetes
2. from manual local build

I search existing post but don't quite understand why the out of box don't seem to be working.

Spark fails with NoClassDefFoundError for org.apache.kafka.common.serialization.StringDeserializer

Apache Kafka: ...StringDeserializer is not an instance of...Deserializer

Why does Spark application fail with "Exception in thread "main" java.lang.NoClassDefFoundError: ...StringDeserializer"?

HELM/Kubernetes

Clone https://github.com/bitnami/charts.git bitnami/spark
using
registry: docker.io
  repository: bitnami/spark
  tag: 2.4.5-debian-10-r87
  tag: 2.4.5-debian-10-r94
Got success with ./bin/run-example SparkPi 10
But got error with ./bin/run-example streaming.JavaDirectKafkaWordCount myBroker myConsumerGroup myTopic

    INFO StreamingExamples: Setting log level to [WARN] for streaming example. To override add a custom log4j.properties to the classpath.
    Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/kafka/common/serialization/StringDeserializer
        at org.apache.spark.examples.streaming.JavaDirectKafkaWordCount.main(JavaDirectKafkaWordCount.java:78)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)
        at org.apache.spark.deploy.JavaMainApplication.start(SparkApplication.scala:52)
        at org.apache.spark.deploy.SparkSubmit.org$apache$spark$deploy$SparkSubmit$$runMain(SparkSubmit.scala:845)
        at org.apache.spark.deploy.SparkSubmit.doRunMain$1(SparkSubmit.scala:161)
        at org.apache.spark.deploy.SparkSubmit.submit(SparkSubmit.scala:184)
        at org.apache.spark.deploy.SparkSubmit.doSubmit(SparkSubmit.scala:86)
        at org.apache.spark.deploy.SparkSubmit$$anon$2.doSubmit(SparkSubmit.scala:920)
        at org.apache.spark.deploy.SparkSubmit$.main(SparkSubmit.scala:929)
        at org.apache.spark.deploy.SparkSubmit.main(SparkSubmit.scala)
    Caused by: java.lang.ClassNotFoundException: org.apache.kafka.common.serialization.StringDeserializer
        at java.net.URLClassLoader.findClass(URLClassLoader.java:382)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:418)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:351)
        ... 13 more

MANUAL LOCAL BUILD

Clone https://github.com/apache/spark.git
./build/mvn -DskipTests clean package
[INFO] BUILD SUCCESS

RAN EXAMPLE SUCCESSFULLY
./bin/run-example SparkPi 10
Pi is roughly 3.1424111424111425

RAN KAFKA EXAMPLE WITH ClassNotFoundException
./bin/run-example streaming.JavaDirectKafkaWordCount myBroker myConsumerGroup myTopic

    INFO StreamingExamples: Setting log level to [WARN] for streaming example. To override add a custom log4j.properties to the classpath.
    Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/kafka/common/serialization/StringDeserializer
        at org.apache.spark.examples.streaming.JavaDirectKafkaWordCount.main(JavaDirectKafkaWordCount.java:78)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)
        at org.apache.spark.deploy.JavaMainApplication.start(SparkApplication.scala:52)
        at org.apache.spark.deploy.SparkSubmit.org$apache$spark$deploy$SparkSubmit$$runMain(SparkSubmit.scala:934)
        at org.apache.spark.deploy.SparkSubmit.doRunMain$1(SparkSubmit.scala:180)
        at org.apache.spark.deploy.SparkSubmit.submit(SparkSubmit.scala:203)
        at org.apache.spark.deploy.SparkSubmit.doSubmit(SparkSubmit.scala:90)
        at org.apache.spark.deploy.SparkSubmit$$anon$2.doSubmit(SparkSubmit.scala:1013)
        at org.apache.spark.deploy.SparkSubmit$.main(SparkSubmit.scala:1022)
        at org.apache.spark.deploy.SparkSubmit.main(SparkSubmit.scala)
    Caused by: java.lang.ClassNotFoundException: org.apache.kafka.common.serialization.StringDeserializer
        at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
        ... 13 more

Answer 1

You need kafka-clients on the classpath (which should be included as part of spark-sql-kafka-0-10 , which is not provided by Spark by default, so you must download it, and add it to the Spark libs directory)

Note: Spark "Streaming" is deprecated. You want Structured Streaming