测试用例参考原文：https://blog.csdn.net/Mathieu66/article/details/110389575

Hudi社区已经正式发布了hudi-0.7.0版本。hudi on flink 最早在0.6.1本版出现，当时还是在master分支，最终切换到了0.7.0分支并经过0.7.0-rc1和0.7.0-rc2两个版本的迭代后毕业。无疑hudi on flink 的支持，使得flink cdc+hudi实时数仓方案得到落实，为此对hudi on flink的开始使用调研及遇到的问题做以下分享。

一、环境介绍

这里以下环境版本示例：
1、hadoop-2.7.2
2、kafka_2.11-2.1.0
3、flink-1.11.2
4、hudi-0.7.0

二、官方源码编译

官方地址：https://hudi.apache.org/
gihub地址：https://github.com/apache/hudi

2.1、 源码下载

git clone https://github.com/apache/hudi.git && cd hudi

2.2、 源码编译

修改hudi/pom.xml
1> 切换release-0.7.0分支，修改pom.xml中hadoop对应集群版本
2> window环境下注释掉<module>hudi-integ-test</module>和<module>packaging/hudi-integ-test-bundle</module>
3> flink-1.11.2对应parquet版本为1.11.1，可修改pom.xml到对应版本（若flink/lib下存在其他本版以该版本保持一致），本次测试不修改保留1.10.1版本

mvn clean package -DskipTests

三、创建测试用例

3.1、创建hudi-conf.properties配置文件

hoodie.datasource.write.recordkey.field=uuid
hoodie.datasource.write.partitionpath.field=ts
bootstrap.servers=hadoop01:9092,hadoop02:9092,hadoop03:9092
hoodie.deltastreamer.keygen.timebased.timestamp.type=EPOCHMILLISECONDS
hoodie.deltastreamer.keygen.timebased.output.dateformat=yyyy/MM/dd
hoodie.datasource.write.keygenerator.class=org.apache.hudi.keygen.TimestampBasedAvroKeyGenerator
hoodie.embed.timeline.server=false
hoodie.deltastreamer.schemaprovider.source.schema.file=hdfs:///tmpdir/hudi/test/config/flink/schema.avsc
hoodie.deltastreamer.schemaprovider.target.schema.file=hdfs:///tmpdir/hudi/test/config/flink/schema.avsc

3.2、创建schema.avsc文件

{
  "type":"record",
  "name":"stock_ticks",
  "fields":[{
     "name": "uuid",
     "type": "string"
  }, {
     "name": "ts",
     "type": "long"
  }, {
     "name": "symbol",
     "type": "string"
  },{
     "name": "year",
     "type": "int"
  },{
     "name": "month",
     "type": "int"
  },{
     "name": "high",
     "type": "double"
  },{
     "name": "low",
     "type": "double"
  },{
     "name": "key",
     "type": "string"
  },{
     "name": "close",
     "type": "double"
  }, {
     "name": "open",
     "type": "double"
  }, {
     "name": "day",
     "type":"string"
  }
]}

3.3、上传到hdfs文件系统

sudo -u hdfs hadoop fs -mkdir -p /tmpdir/hudi/test/config/flink
hadoop fs -put schema.avsc /tmpdir/hudi/test/config/flink/
hadoop fs -put hudi-conf.properties /tmpdir/hudi/test/config/flink/

3.4、创建kafka测试topic

#创建主题
/opt/apps/kafka/bin/kafka-topics.sh --create --zookeeper hadoop01:2181,hadoop02:2181,hadoop03:2181/kafka --replication-factor 2 --partitions 3 --topic mytest
#查看主题
/opt/apps/kafka/bin/kafka-topics.sh --list --zookeeper hadoop01:2181,hadoop02:2181,hadoop03:2181/kafka
#生产者（测试）
/opt/apps/kafka/bin/kafka-console-producer.sh --broker-list hadoop01:9092,hadoop02:9092,hadoop03:9092 --topic mytest

测试数据

{"close":0.27172637588467297,"day":"2","high":0.4493211149337879,"key":"840ef1","low":0.030714155934507215,"month":11,"open":0.7762668153935262,"symbol":"77c-40d6-8412-6859d4757727","ts":1608361070161,"uuid":"840ef1ff-b77c-40d6-8412-6859d4757727","year":120}

6、提交命令及参数介绍

/opt/flink-1.11.2/bin/flink run -c org.apache.hudi.HoodieFlinkStreamer -m yarn-cluster -d -yjm 2048 -ytm 3096 -ys 4 -ynm hudi_on_flink_test \
-p 1 -yD env.java.opts=" -XX:+TraceClassPaths  -XX:+TraceClassLoading" hudi-flink-bundle_2.11-0.7.0.jar --kafka-topic mytest --kafka-group-id hudi_on_flink \
--kafka-bootstrap-servers hadoop01:9092,hadoop02:9092,hadoop03:9092 --table-type COPY_ON_WRITE --target-base-path hdfs:///tmpdir/hudi/test/data/hudi_on_flink \
--target-table hudi_on_flink --props hdfs:///tmpdir/hudi/test/config/flink/hudi-conf.properties --checkpoint-interval 3000 \
--flink-checkpoint-path hdfs:///flink/hudi/hudi_on_flink_cp

HoodieFlinkStreamer参数介绍

四、发现问题

新搭建的测试环境未做过jar包的兼容性整合。job能正常启动后，当消费消息write_process时会发生如下异常：

java.io.IOException: Could not perform checkpoint 6 for operator write_process (1/1).
    at org.apache.flink.streaming.runtime.tasks.StreamTask.triggerCheckpointOnBarrier(StreamTask.java:892)
    at org.apache.flink.streaming.runtime.io.CheckpointBarrierHandler.notifyCheckpoint(CheckpointBarrierHandler.java:113)
    at org.apache.flink.streaming.runtime.io.CheckpointBarrierAligner.processBarrier(CheckpointBarrierAligner.java:137)
    at org.apache.flink.streaming.runtime.io.CheckpointedInputGate.pollNext(CheckpointedInputGate.java:93)
    at org.apache.flink.streaming.runtime.io.StreamTaskNetworkInput.emitNext(StreamTaskNetworkInput.java:158)
    at org.apache.flink.streaming.runtime.io.StreamOneInputProcessor.processInput(StreamOneInputProcessor.java:67)
    at org.apache.flink.streaming.runtime.tasks.StreamTask.processInput(StreamTask.java:351)
    at org.apache.flink.streaming.runtime.tasks.mailbox.MailboxProcessor.runMailboxStep(MailboxProcessor.java:191)
    at org.apache.flink.streaming.runtime.tasks.mailbox.MailboxProcessor.runMailboxLoop(MailboxProcessor.java:181)
    at org.apache.flink.streaming.runtime.tasks.StreamTask.runMailboxLoop(StreamTask.java:566)
    at org.apache.flink.streaming.runtime.tasks.StreamTask.invoke(StreamTask.java:536)
    at org.apache.flink.runtime.taskmanager.Task.doRun(Task.java:721)
    at org.apache.flink.runtime.taskmanager.Task.run(Task.java:546)
    at java.lang.Thread.run(Thread.java:748)
Caused by: org.apache.flink.runtime.checkpoint.CheckpointException: Could not complete snapshot 6 for operator write_process (1/1). Failure reason: Checkpoint was declined.
    at org.apache.flink.streaming.api.operators.StreamOperatorStateHandler.snapshotState(StreamOperatorStateHandler.java:215)
    at org.apache.flink.streaming.api.operators.StreamOperatorStateHandler.snapshotState(StreamOperatorStateHandler.java:156)
    at org.apache.flink.streaming.api.operators.AbstractStreamOperator.snapshotState(AbstractStreamOperator.java:314)
    at org.apache.flink.streaming.runtime.tasks.SubtaskCheckpointCoordinatorImpl.checkpointStreamOperator(SubtaskCheckpointCoordinatorImpl.java:614)
    at org.apache.flink.streaming.runtime.tasks.SubtaskCheckpointCoordinatorImpl.buildOperatorSnapshotFutures(SubtaskCheckpointCoordinatorImpl.java:540)
    at org.apache.flink.streaming.runtime.tasks.SubtaskCheckpointCoordinatorImpl.takeSnapshotSync(SubtaskCheckpointCoordinatorImpl.java:507)
    at org.apache.flink.streaming.runtime.tasks.SubtaskCheckpointCoordinatorImpl.checkpointState(SubtaskCheckpointCoordinatorImpl.java:266)
    at org.apache.flink.streaming.runtime.tasks.StreamTask.lambda$performCheckpoint$8(StreamTask.java:921)
    at org.apache.flink.streaming.runtime.tasks.StreamTaskActionExecutor$1.runThrowing(StreamTaskActionExecutor.java:47)
    at org.apache.flink.streaming.runtime.tasks.StreamTask.performCheckpoint(StreamTask.java:911)
    at org.apache.flink.streaming.runtime.tasks.StreamTask.triggerCheckpointOnBarrier(StreamTask.java:879)
    ... 13 more
Caused by: org.apache.hudi.exception.HoodieUpsertException: Failed to upsert for commit time 20210125212048
    at org.apache.hudi.table.action.commit.AbstractWriteHelper.write(AbstractWriteHelper.java:62)
    at org.apache.hudi.table.action.commit.FlinkUpsertCommitActionExecutor.execute(FlinkUpsertCommitActionExecutor.java:47)
    at org.apache.hudi.table.HoodieFlinkCopyOnWriteTable.upsert(HoodieFlinkCopyOnWriteTable.java:66)
    at org.apache.hudi.table.HoodieFlinkCopyOnWriteTable.upsert(HoodieFlinkCopyOnWriteTable.java:58)
    at org.apache.hudi.client.HoodieFlinkWriteClient.upsert(HoodieFlinkWriteClient.java:110)
    at org.apache.hudi.operator.KeyedWriteProcessFunction.snapshotState(KeyedWriteProcessFunction.java:121)
    at org.apache.flink.streaming.util.functions.StreamingFunctionUtils.trySnapshotFunctionState(StreamingFunctionUtils.java:120)
    at org.apache.flink.streaming.util.functions.StreamingFunctionUtils.snapshotFunctionState(StreamingFunctionUtils.java:101)
    at org.apache.flink.streaming.api.operators.AbstractUdfStreamOperator.snapshotState(AbstractUdfStreamOperator.java:90)
    at org.apache.hudi.operator.KeyedWriteProcessOperator.snapshotState(KeyedWriteProcessOperator.java:58)
    at org.apache.flink.streaming.api.operators.StreamOperatorStateHandler.snapshotState(StreamOperatorStateHandler.java:186)
    ... 23 more
Caused by: java.lang.RuntimeException: org.apache.hudi.exception.HoodieException: org.apache.hudi.exception.HoodieException: java.util.concurrent.ExecutionException: java.lang.NoClassDefFoundError: org/apache/hudi/avro/HoodieAvroWriteSupport
    at org.apache.hudi.client.utils.LazyIterableIterator.next(LazyIterableIterator.java:121)
    at java.util.Iterator.forEachRemaining(Iterator.java:116)
    at org.apache.hudi.table.action.commit.BaseFlinkCommitActionExecutor.lambda$execute$0(BaseFlinkCommitActionExecutor.java:120)
    at java.util.LinkedHashMap.forEach(LinkedHashMap.java:684)
    at org.apache.hudi.table.action.commit.BaseFlinkCommitActionExecutor.execute(BaseFlinkCommitActionExecutor.java:118)
    at org.apache.hudi.table.action.commit.BaseFlinkCommitActionExecutor.execute(BaseFlinkCommitActionExecutor.java:68)
    at org.apache.hudi.table.action.commit.AbstractWriteHelper.write(AbstractWriteHelper.java:55)
    ... 33 more
Caused by: org.apache.hudi.exception.HoodieException: org.apache.hudi.exception.HoodieException: java.util.concurrent.ExecutionException: java.lang.NoClassDefFoundError: org/apache/hudi/avro/HoodieAvroWriteSupport
    at org.apache.hudi.execution.FlinkLazyInsertIterable.computeNext(FlinkLazyInsertIterable.java:73)
    at org.apache.hudi.execution.FlinkLazyInsertIterable.computeNext(FlinkLazyInsertIterable.java:38)
    at org.apache.hudi.client.utils.LazyIterableIterator.next(LazyIterableIterator.java:119)
    ... 39 more
Caused by: org.apache.hudi.exception.HoodieException: java.util.concurrent.ExecutionException: java.lang.NoClassDefFoundError: org/apache/hudi/avro/HoodieAvroWriteSupport
    at org.apache.hudi.common.util.queue.BoundedInMemoryExecutor.execute(BoundedInMemoryExecutor.java:143)
    at org.apache.hudi.execution.FlinkLazyInsertIterable.computeNext(FlinkLazyInsertIterable.java:69)
    ... 41 more
Caused by: java.util.concurrent.ExecutionException: java.lang.NoClassDefFoundError: org/apache/hudi/avro/HoodieAvroWriteSupport
    at java.util.concurrent.FutureTask.report(FutureTask.java:122)
    at java.util.concurrent.FutureTask.get(FutureTask.java:192)
    at org.apache.hudi.common.util.queue.BoundedInMemoryExecutor.execute(BoundedInMemoryExecutor.java:141)
    ... 42 more
Caused by: java.lang.NoClassDefFoundError: org/apache/hudi/avro/HoodieAvroWriteSupport
    at org.apache.hudi.io.storage.HoodieFileWriterFactory.newParquetFileWriter(HoodieFileWriterFactory.java:59)
    at org.apache.hudi.io.storage.HoodieFileWriterFactory.getFileWriter(HoodieFileWriterFactory.java:47)
    at org.apache.hudi.io.HoodieCreateHandle.<init>(HoodieCreateHandle.java:85)
    at org.apache.hudi.io.HoodieCreateHandle.<init>(HoodieCreateHandle.java:66)
    at org.apache.hudi.io.CreateHandleFactory.create(CreateHandleFactory.java:34)
    at org.apache.hudi.execution.CopyOnWriteInsertHandler.consumeOneRecord(CopyOnWriteInsertHandler.java:83)
    at org.apache.hudi.execution.CopyOnWriteInsertHandler.consumeOneRecord(CopyOnWriteInsertHandler.java:40)
    at org.apache.hudi.common.util.queue.BoundedInMemoryQueueConsumer.consume(BoundedInMemoryQueueConsumer.java:37)
    at org.apache.hudi.common.util.queue.BoundedInMemoryExecutor.lambda$null$2(BoundedInMemoryExecutor.java:121)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
    ... 1 more

五、定位问题

5.1、查看编译的jar包

发现存在该类，于是猜测与集群中有jar冲突

5.2、是否和集群中有hudi相关jar冲突（该类属于hudi-common包）

通过 find /opt -name "*hudi*.jar" 查找。并未发现有相关的jar（曾切换到不同版本的hadoop集群测试结果一致异常）
结论：不是jar冲突引起。

5.3、打开classloadtrace查看类加载情况

添加 -yD env.java.opts="-XX:+TraceClassLoading -XX:+TraceClassPaths"参数，查看HoodieAvroWriteSupport 没有被加载。于是开始定位异常代码位置，猜测为静态代码中初始化该类时就已经异常导致，将 new AvroSchemaConverter().convert(schema)写到外面来定位具体的缺失类

5.4、通过查看hudi-flink-bundle编译包，除了parquet-avro,其他parquet相关的依赖并没有被编译进来。

到编译的本地maven依赖仓库找出以下parquet相关jar拷贝到flink/lib下尝试解决

5.5、根据HadoopReadOptions类加载信息判断

查看classloadtrace信息已加载HadoopReadOptions来确认parquet-hadoop包已经被加载，所以确定ParquetInputFormat类（来自parquet-hadoop）的异常由其他缺失造成，于是查看HadoopReadOptions类中引入的类及ParquetInputFormat继承的父类等。最终发现ParquetInputFormat继承的父类org.apache.hadoop.mapreduce.lib.input.FileInputFormat(所属hadoop-mapreduce-client-coreye-x.x.x.jar)并未被加载。

5.6、将hadoop-mapreduce-client-core-x.x.x.jar拷贝到flink/lib下解决

重新提交任务。若发现有如下异常,删除hdfs表目录下的文件重新提交（由于之前步骤的异常造成的损坏）。

java.io.IOException: Could not perform checkpoint 3 for operator instant_generator (1/1).
    at org.apache.flink.streaming.runtime.tasks.StreamTask.triggerCheckpointOnBarrier(StreamTask.java:892)
    at org.apache.flink.streaming.runtime.io.CheckpointBarrierHandler.notifyCheckpoint(CheckpointBarrierHandler.java:113)
    at org.apache.flink.streaming.runtime.io.CheckpointBarrierAligner.processBarrier(CheckpointBarrierAligner.java:137)
    at org.apache.flink.streaming.runtime.io.CheckpointedInputGate.pollNext(CheckpointedInputGate.java:93)
    at org.apache.flink.streaming.runtime.io.StreamTaskNetworkInput.emitNext(StreamTaskNetworkInput.java:158)
    at org.apache.flink.streaming.runtime.io.StreamOneInputProcessor.processInput(StreamOneInputProcessor.java:67)
    at org.apache.flink.streaming.runtime.tasks.StreamTask.processInput(StreamTask.java:351)
    at org.apache.flink.streaming.runtime.tasks.mailbox.MailboxProcessor.runMailboxStep(MailboxProcessor.java:191)
    at org.apache.flink.streaming.runtime.tasks.mailbox.MailboxProcessor.runMailboxLoop(MailboxProcessor.java:181)
    at org.apache.flink.streaming.runtime.tasks.StreamTask.runMailboxLoop(StreamTask.java:566)
    at org.apache.flink.streaming.runtime.tasks.StreamTask.invoke(StreamTask.java:536)
    at org.apache.flink.runtime.taskmanager.Task.doRun(Task.java:721)
    at org.apache.flink.runtime.taskmanager.Task.run(Task.java:546)
    at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.InterruptedException: Last instant costs more than 10 second, stop task now
    at org.apache.hudi.operator.InstantGenerateOperator.doCheck(InstantGenerateOperator.java:199)
    at org.apache.hudi.operator.InstantGenerateOperator.prepareSnapshotPreBarrier(InstantGenerateOperator.java:119)
    at org.apache.flink.streaming.runtime.tasks.OperatorChain.prepareSnapshotPreBarrier(OperatorChain.java:266)
    at org.apache.flink.streaming.runtime.tasks.SubtaskCheckpointCoordinatorImpl.checkpointState(SubtaskCheckpointCoordinatorImpl.java:249)
    at org.apache.flink.streaming.runtime.tasks.StreamTask.lambda$performCheckpoint$8(StreamTask.java:921)
    at org.apache.flink.streaming.runtime.tasks.StreamTaskActionExecutor$1.runThrowing(StreamTaskActionExecutor.java:47)
    at org.apache.flink.streaming.runtime.tasks.StreamTask.performCheckpoint(StreamTask.java:911)
    at org.apache.flink.streaming.runtime.tasks.StreamTask.triggerCheckpointOnBarrier(StreamTask.java:879)
    ... 13 more

5.7 解决问题

问题总结

上述问题基本是由于集群没有相关jar包导致，根据上面的问题定位方法能解决大部分在遇到NoClassDefFoundError、ClassNotFoundException等异常问题。