编译hbase-sink

准备环境

• linux系统CentOS 7

安装git

su - root
yum install git-core

git clone https://github.com/thbzh/kafka-connect-hbase.git

安装maven

• 如果没有安装wget，安装wget

yum -y install wget

• 用wget下载maven（其它方式下载也行）

wget http://mirror.bit.edu.cn/apache/maven/maven-3/3.6.0/binaries/apache-maven-3.6.0-bin.tar.gz

• 安装

tar -xvzf apache-maven-3.6.0-bin.tar.gz
mkdir /usr/local/maven
mv apache-maven-3.6.0 /usr/local/maven

• 配置环境变量

vi /etc/profile 

添加如下

## MAVEN CONFIG ## 
export MAVEN_HOME=/usr/local/maven/apache-maven-3.6.0
export PATH=$MAVEN_HOME/bin:$PATH

• 验证

$mvn -v
Apache Maven 3.6.0 (1edded0938998edf8bf061f1ceb3cfdeccf443fe; 2018-06-18T02:33:14+08:00)
Maven home: /home/crm_core_account/.apache-maven-3.5.4
Java version: 1.8.0_121, vendor: Oracle Corporation, runtime: /software/servers/jdk1.8.0_121/jre
Default locale: en_US, platform encoding: UTF-8
OS name: "linux", version: "3.10.0-327.28.3.el7.x86_64", arch: "amd64", family: "unix"

修改代码

fork到自己的github下

hbase-sink github地址：https://github.com/nishutayal/kafka-connect-hbase

注： 如果不想管理代码，可以不用fork

使用git push到本地

git clone https://github.com/nishutayal/kafka-connect-hbase.git

修改代码

可以fork代码到自己properties中，git clone到windows系统，用idea编译，在git pull的项目中。编译时，从自己的repositories中git clone。
修改代码AvroEventParser如下：

maven 编译

mvn package -Dmaven.test.skip=true

注：hbase-sink如果package不通过，可以跳过测试部分。
编译完后，target下会有两个jar包，如下：

kafka-connect-hbase-1.0.1.jar  // 带依赖 
hbase-sink.jar                      // 不带依赖

启动hbase-sink

上传jar包到服务器

• 将kafka-connect-hbase-1.0.1.jar上传到服务器上
  目录为/home/kafka/confluent-5.1.2/share/java/kafka-connect-hbase
• 将hbase-site.xml打到jar包中

jar -uvf kafka-connect-hbase-1.0.1.jar hbase-site.xml

sink properties

$CONFLUENT_HOME/etc/kafka-connect-hbase/hbase-sink.properties

connector.class=io.svectors.hbase.sink.HBaseSinkConnector
tasks.max=1
topics=test
zookeeper.quorum=bigdata1:2181
event.parser.class=io.svectors.hbase.parser.AvroEventParser
hbase.table.name=kafka_test
hbase.kafka_test.rowkey.columns=a
hbase.kafka_test.rowkey.delimiter=|
hbase.kafka_test.family=cf

启动sink

$CONFLUENT_HOME/bin/connect-standalone $CONFLUENT_HOME/etc/schema-registry/connect-avro-standalone.properties $CONFLUENT_HOME/etc/kafka-connect-hbase/hbase-sink.properties

用 avro console测试

bin/kafka-avro-console-producer --broker-list appserver5:9092 --topic test --property value.schema='{"type":"record","name":"record","fields":[{"name":"id","type":"int"}, {"name":"name", "type": "string"}]}'

#insert at prompt
{"id": 10, "name": "foo"}
{"id": 20, "name": "bar"}
{"id": 30, "name": "xiaocan"}

数据库查询

hbase shell
list
scan ‘kafka_test’

实践中遇到的问题

启动sink报错

$CONFLUENT_HOME/bin/connect-standalone $CONFLUENT_HOME/etc/schema-registry/connect-avro-standalone.properties $CONFLUENT_HOME/etc/kafka-connect-hbase/hbase-sink.properties

报错如下：

[2019-04-06 17:29:37,164] INFO Kafka Connect standalone worker initialization took 3796ms (org.apache.kafka.connect.cli.ConnectStandalone:96)
[2019-04-06 17:29:37,164] INFO Kafka Connect starting (org.apache.kafka.connect.runtime.Connect:50)
[2019-04-06 17:29:37,164] INFO Herder starting (org.apache.kafka.connect.runtime.standalone.StandaloneHerder:87)
[2019-04-06 17:29:37,164] INFO Worker starting (org.apache.kafka.connect.runtime.Worker:172)
[2019-04-06 17:29:37,164] INFO Starting FileOffsetBackingStore with file /tmp/connect.offsets (org.apache.kafka.connect.storage.FileOffsetBackingStore:58)
[2019-04-06 17:29:37,166] INFO Worker started (org.apache.kafka.connect.runtime.Worker:177)
[2019-04-06 17:29:37,166] INFO Herder started (org.apache.kafka.connect.runtime.standalone.StandaloneHerder:89)
[2019-04-06 17:29:37,166] INFO Kafka Connect started (org.apache.kafka.connect.runtime.Connect:55)
[2019-04-06 17:29:37,168] ERROR Failed to create job for /home/kafka/confluent-5.1.2/etc/kafka-connect-hbase/hbase-sink.properties (org.apache.kafka.connect.cli.ConnectStandalone:108)
[2019-04-06 17:29:37,168] ERROR Stopping after connector error (org.apache.kafka.connect.cli.ConnectStandalone:119)
java.util.concurrent.ExecutionException: org.apache.kafka.connect.errors.ConnectException: Failed to find any class that implements Connector and which name matches io.svectors.hbase.sink.HBaseSinkConnector, available connectors are: PluginDesc{klass=class org.apache.kafka.connect.file.FileStreamSinkConnector, name='org.apache.kafka.connect.file.FileStreamSinkConnector', version='2.1.1-cp1', encodedVersion=2.1.1-cp1, type=sink, typeName='sink', location='classpath'}, PluginDesc{klass=class org.apache.kafka.connect.file.FileStreamSourceConnector, name='org.apache.kafka.connect.file.FileStreamSourceConnector', version='2.1.1-cp1', encodedVersion=2.1.1-cp1, type=source, typeName='source', location='classpath'}, PluginDesc{klass=class org.apache.kafka.connect.tools.MockConnector, name='org.apache.kafka.connect.tools.MockConnector', version='2.1.1-cp1', encodedVersion=2.1.1-cp1, type=connector, typeName='connector', location='classpath'}, PluginDesc{klass=class org.apache.kafka.connect.tools.MockSinkConnector, name='org.apache.kafka.connect.tools.MockSinkConnector', version='2.1.1-cp1', encodedVersion=2.1.1-cp1, type=sink, typeName='sink', location='classpath'}, PluginDesc{klass=class org.apache.kafka.connect.tools.MockSourceConnector, name='org.apache.kafka.connect.tools.MockSourceConnector', version='2.1.1-cp1', encodedVersion=2.1.1-cp1, type=source, typeName='source', location='classpath'}, PluginDesc{klass=class org.apache.kafka.connect.tools.SchemaSourceConnector, name='org.apache.kafka.connect.tools.SchemaSourceConnector', version='2.1.1-cp1', encodedVersion=2.1.1-cp1, type=source, typeName='source', location='classpath'}, PluginDesc{klass=class org.apache.kafka.connect.tools.VerifiableSinkConnector, name='org.apache.kafka.connect.tools.VerifiableSinkConnector', version='2.1.1-cp1', encodedVersion=2.1.1-cp1, type=source, typeName='source', location='classpath'}, PluginDesc{klass=class org.apache.kafka.connect.tools.VerifiableSourceConnector, name='org.apache.kafka.connect.tools.VerifiableSourceConnector', version='2.1.1-cp1', encodedVersion=2.1.1-cp1, type=source, typeName='source', location='classpath'}
        at org.apache.kafka.connect.util.ConvertingFutureCallback.result(ConvertingFutureCallback.java:79)
        at org.apache.kafka.connect.util.ConvertingFutureCallback.get(ConvertingFutureCallback.java:66)
        at org.apache.kafka.connect.cli.ConnectStandalone.main(ConnectStandalone.java:116)
Caused by: org.apache.kafka.connect.errors.ConnectException: Failed to find any class that implements Connector and which name matches io.svectors.hbase.sink.HBaseSinkConnector, available connectors are: PluginDesc{klass=class org.apache.kafka.connect.file.FileStreamSinkConnector, name='org.apache.kafka.connect.file.FileStreamSinkConnector', version='2.1.1-cp1', encodedVersion=2.1.1-cp1, type=sink, typeName='sink', location='classpath'}, PluginDesc{klass=class org.apache.kafka.connect.file.FileStreamSourceConnector, name='org.apache.kafka.connect.file.FileStreamSourceConnector', version='2.1.1-cp1', encodedVersion=2.1.1-cp1, type=source, typeName='source', location='classpath'}, PluginDesc{klass=class org.apache.kafka.connect.tools.MockConnector, name='org.apache.kafka.connect.tools.MockConnector', version='2.1.1-cp1', encodedVersion=2.1.1-cp1, type=connector, typeName='connector', location='classpath'}, PluginDesc{klass=class org.apache.kafka.connect.tools.MockSinkConnector, name='org.apache.kafka.connect.tools.MockSinkConnector', version='2.1.1-cp1', encodedVersion=2.1.1-cp1, type=sink, typeName='sink', location='classpath'}, PluginDesc{klass=class org.apache.kafka.connect.tools.MockSourceConnector, name='org.apache.kafka.connect.tools.MockSourceConnector', version='2.1.1-cp1', encodedVersion=2.1.1-cp1, type=source, typeName='source', location='classpath'}, PluginDesc{klass=class org.apache.kafka.connect.tools.SchemaSourceConnector, name='org.apache.kafka.connect.tools.SchemaSourceConnector', version='2.1.1-cp1', encodedVersion=2.1.1-cp1, type=source, typeName='source', location='classpath'}, PluginDesc{klass=class org.apache.kafka.connect.tools.VerifiableSinkConnector, name='org.apache.kafka.connect.tools.VerifiableSinkConnector', version='2.1.1-cp1', encodedVersion=2.1.1-cp1, type=source, typeName='source', location='classpath'}, PluginDesc{klass=class org.apache.kafka.connect.tools.VerifiableSourceConnector, name='org.apache.kafka.connect.tools.VerifiableSourceConnector', version='2.1.1-cp1', encodedVersion=2.1.1-cp1, type=source, typeName='source', location='classpath'}
        at org.apache.kafka.connect.runtime.isolation.Plugins.newConnector(Plugins.java:179)
        at org.apache.kafka.connect.runtime.AbstractHerder.getConnector(AbstractHerder.java:382)
        at org.apache.kafka.connect.runtime.AbstractHerder.validateConnectorConfig(AbstractHerder.java:261)
        at org.apache.kafka.connect.runtime.standalone.StandaloneHerder.putConnectorConfig(StandaloneHerder.java:188)
        at org.apache.kafka.connect.cli.ConnectStandalone.main(ConnectStandalone.java:113)
[2019-04-06 17:29:37,170] INFO Kafka Connect stopping (org.apache.kafka.connect.runtime.Connect:65)
[2019-04-06 17:29:37,170] INFO Stopping REST server (org.apache.kafka.connect.runtime.rest.RestServer:226)
[2019-04-06 17:29:37,175] INFO Stopped http_9083@3506d826{HTTP/1.1,[http/1.1]}{0.0.0.0:9083} (org.eclipse.jetty.server.AbstractConnector:341)
[2019-04-06 17:29:37,176] INFO node0 Stopped scavenging (org.eclipse.jetty.server.session:167)
[2019-04-06 17:29:37,183] INFO Stopped o.e.j.s.ServletContextHandler@6de0f580{/,null,UNAVAILABLE} (org.eclipse.jetty.server.handler.ContextHandler:1040)
[2019-04-06 17:29:37,184] INFO REST server stopped (org.apache.kafka.connect.runtime.rest.RestServer:244)
[2019-04-06 17:29:37,184] INFO Herder stopping (org.apache.kafka.connect.runtime.standalone.StandaloneHerder:94)
[2019-04-06 17:29:37,184] INFO Worker stopping (org.apache.kafka.connect.runtime.Worker:184)
[2019-04-06 17:29:37,185] INFO Stopped FileOffsetBackingStore (org.apache.kafka.connect.storage.FileOffsetBackingStore:66)
[2019-04-06 17:29:37,185] INFO Worker stopped (org.apache.kafka.connect.runtime.Worker:205)
[2019-04-06 17:29:37,186] INFO Herder stopped (org.apache.kafka.connect.runtime.standalone.StandaloneHerder:111)
[2019-04-06 17:29:37,186] INFO Kafka Connect stopped (org.apache.kafka.connect.runtime.Connect:70)

排查问题

• 参考资料
  https://stackoverflow.com/questions/53412622/kafka-connect-cant-find-connector
  https://github.com/DataReply/kafka-connect-mongodb/issues/23

• 查看配置
  etc/schema-registry/connect-avro-standalone.properties

【分析】：share/java为相对路径，当不在CONFLUENT_HOME启动时，是读不到此文件夹的

• 修改配置

plugin.path=/home/kafka/confluent-5.1.2/share/java

• 再次启动成功
  命令见上面

avro console发送消息报错

bin/kafka-avro-console-producer --broker-list appserver5:9092 --topic test --property value.schema='{"type":"record","name":"record","fields":[{"name":"id","type":"int"}, {"name":"name", "type": "string"}]}'

#insert at prompt
{"id": 10, "name": "foo"}
{"id": 30, "name": "xiaocan"}

报错如下

org.apache.kafka.common.errors.SerializationException: Error serializing Avro message
Caused by: com.fasterxml.jackson.core.JsonParseException: Unexpected character ('<' (code 60)): expected a valid value (number, String, array, object, 'true', 'false' or 'null')
 at [Source: (sun.net.www.protocol.http.HttpURLConnection$HttpInputStream); line: 1, column: 2]
        at com.fasterxml.jackson.core.JsonParser._constructError(JsonParser.java:1804)
        at com.fasterxml.jackson.core.base.ParserMinimalBase._reportError(ParserMinimalBase.java:669)
        at com.fasterxml.jackson.core.base.ParserMinimalBase._reportUnexpectedChar(ParserMinimalBase.java:567)
        at com.fasterxml.jackson.core.json.UTF8StreamJsonParser._handleUnexpectedValue(UTF8StreamJsonParser.java:2624)
        at com.fasterxml.jackson.core.json.UTF8StreamJsonParser._nextTokenNotInObject(UTF8StreamJsonParser.java:826)
        at com.fasterxml.jackson.core.json.UTF8StreamJsonParser.nextToken(UTF8StreamJsonParser.java:723)
        at com.fasterxml.jackson.databind.ObjectMapper._initForReading(ObjectMapper.java:4141)
        at com.fasterxml.jackson.databind.ObjectMapper._readMapAndClose(ObjectMapper.java:4000)
        at com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:3077)
        at io.confluent.kafka.schemaregistry.client.rest.RestService.sendHttpRequest(RestService.java:194)
        at io.confluent.kafka.schemaregistry.client.rest.RestService.httpRequest(RestService.java:235)
        at io.confluent.kafka.schemaregistry.client.rest.RestService.registerSchema(RestService.java:326)
        at io.confluent.kafka.schemaregistry.client.rest.RestService.registerSchema(RestService.java:318)
        at io.confluent.kafka.schemaregistry.client.rest.RestService.registerSchema(RestService.java:313)
        at io.confluent.kafka.schemaregistry.client.CachedSchemaRegistryClient.registerAndGetId(CachedSchemaRegistryClient.java:118)
        at io.confluent.kafka.schemaregistry.client.CachedSchemaRegistryClient.register(CachedSchemaRegistryClient.java:155)
        at io.confluent.kafka.serializers.AbstractKafkaAvroSerializer.serializeImpl(AbstractKafkaAvroSerializer.java:79)
        at io.confluent.kafka.formatter.AvroMessageReader.readMessage(AvroMessageReader.java:181)
        at kafka.tools.ConsoleProducer$.main(ConsoleProducer.scala:54)
        at kafka.tools.ConsoleProducer.main(ConsoleProducer.scala)

排查问题

https://github.com/Landoop/stream-reactor/issues/148

初步断定是之前修改端口号，导致连接不到服务

• 之前9021和8081对换过端口号
  修改配置$CONFLUENT_HOME/etc/schema-registry/connect-avro-standalone.properties

key.converter.schema.registry.url=http://appserver5:8081 => key.converter.schema.registry.url=http://appserver5:9021
value.converter.schema.registry.url=http://appserver5:8081 => value.converter.schema.registry.url=http://appserver5:9021

【结论】问题没有解决

• 验证schema-registry

curl http://appserver5:9021 

【注】schema-registry默认端口号为8081，和端口9021对调
【结论】服务正常

• 显示指定chema.registry.url

bin/kafka-avro-console-producer --broker-list appserver5:9092 --topic test --property value.schema='{"type":"record","name":"record","fields":[{"name":"id","type":"int"}, {"name":"name", "type": "string"}]}'  --property  schema.registry.url=http://appserver5:9021

【结论】发送消息正常，问题解决

hbase-sink处理消息报错

java.lang.NullPointerException
        at org.apache.hadoop.hbase.client.Put.(Put.java:68)
        at org.apache.hadoop.hbase.client.Put.(Put.java:58)
        at io.svectors.hbase.util.ToPutFunction.apply(ToPutFunction.java:73)
        at io.svectors.hbase.sink.HBaseSinkTask.lambda$null$0(HBaseSinkTask.java:76)
        at java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:193)
        at java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1382)
        at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:481)
        at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:471)
        at java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:708)
        at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
        at java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:499)
        at io.svectors.hbase.sink.HBaseSinkTask.lambda$put$1(HBaseSinkTask.java:76)
        at java.util.stream.Collectors.lambda$toMap$58(Collectors.java:1321)
        at java.util.stream.ReduceOps$3ReducingSink.accept(ReduceOps.java:169)
        at java.util.HashMap$EntrySpliterator.forEachRemaining(HashMap.java:1699)
        at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:481)
        at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:471)
        at java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:708)
        at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
        at java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:499)
        at io.svectors.hbase.sink.HBaseSinkTask.put(HBaseSinkTask.java:75)
        at org.apache.kafka.connect.runtime.WorkerSinkTask.deliverMessages(WorkerSinkTask.java:565)
        at org.apache.kafka.connect.runtime.WorkerSinkTask.poll(WorkerSinkTask.java:323)
        at org.apache.kafka.connect.runtime.WorkerSinkTask.iteration(WorkerSinkTask.java:226)
        at org.apache.kafka.connect.runtime.WorkerSinkTask.execute(WorkerSinkTask.java:194)
        at org.apache.kafka.connect.runtime.WorkerTask.doRun(WorkerTask.java:175)
        at org.apache.kafka.connect.runtime.WorkerTask.run(WorkerTask.java:219)
        at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
        at java.util.concurrent.FutureTask.run(FutureTask.java:266)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
        at java.lang.Thread.run(Thread.java:748)
[2019-04-10 12:59:41,799] ERROR WorkerSinkTask{id=kafka-cdc-hbase-0} Task threw an uncaught and unrecoverable exception (org.apache.kafka.connect.runtime.WorkerTask:177)
org.apache.kafka.connect.errors.ConnectException: Exiting WorkerSinkTask due to unrecoverable exception.
        at org.apache.kafka.connect.runtime.WorkerSinkTask.deliverMessages(WorkerSinkTask.java:587)
        at org.apache.kafka.connect.runtime.WorkerSinkTask.poll(WorkerSinkTask.java:323)
        at org.apache.kafka.connect.runtime.WorkerSinkTask.iteration(WorkerSinkTask.java:226)
        at org.apache.kafka.connect.runtime.WorkerSinkTask.execute(WorkerSinkTask.java:194)
        at org.apache.kafka.connect.runtime.WorkerTask.doRun(WorkerTask.java:175)
        at org.apache.kafka.connect.runtime.WorkerTask.run(WorkerTask.java:219)
        at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
        at java.util.concurrent.FutureTask.run(FutureTask.java:266)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
        at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.NullPointerException
        at org.apache.hadoop.hbase.client.Put.(Put.java:68)
        at org.apache.hadoop.hbase.client.Put.(Put.java:58)
        at io.svectors.hbase.util.ToPutFunction.apply(ToPutFunction.java:73)
        at io.svectors.hbase.sink.HBaseSinkTask.lambda$null$0(HBaseSinkTask.java:76)
        at java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:193)
        at java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1382)
        at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:481)
        at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:471)
        at java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:708)
        at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
        at java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:499)
        at io.svectors.hbase.sink.HBaseSinkTask.lambda$put$1(HBaseSinkTask.java:76)
        at java.util.stream.Collectors.lambda$toMap$58(Collectors.java:1321)
        at java.util.stream.ReduceOps$3ReducingSink.accept(ReduceOps.java:169)
        at java.util.HashMap$EntrySpliterator.forEachRemaining(HashMap.java:1699)
        at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:481)
        at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:471)
        at java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:708)
        at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
        at java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:499)
        at io.svectors.hbase.sink.HBaseSinkTask.put(HBaseSinkTask.java:75)
        at org.apache.kafka.connect.runtime.WorkerSinkTask.deliverMessages(WorkerSinkTask.java:565)
        ... 10 more

• 根据exception查看源码，发现rowkey是null

• 查看配置文件

【结论】配置文件rowkey字段配置错误

kafka-avro-console-producer VALUE_NULL

bin/kafka-avro-console-producer --broker-list appserver5:9092 --topic test --property value.schema='{"type":"record","name":"record","fields":[{"name":"id","type":"int"}, {"name":"name", "type": "string"}]}'

{"id": 40, "name": null}

报错如下：

org.apache.kafka.common.errors.SerializationException: Error deserializing json {"id": 40, "name": null} to Avro of schema {"type":"record","name":"record","fields":[{"name":"id","type":"int"},{"name":"name","type":"string"}]}
Caused by: org.apache.avro.AvroTypeException: Expected string. Got VALUE_NULL
        at org.apache.avro.io.JsonDecoder.error(JsonDecoder.java:698)
        at org.apache.avro.io.JsonDecoder.readString(JsonDecoder.java:227)
        at org.apache.avro.io.JsonDecoder.readString(JsonDecoder.java:214)
        at org.apache.avro.io.ResolvingDecoder.readString(ResolvingDecoder.java:201)
        at org.apache.avro.generic.GenericDatumReader.readString(GenericDatumReader.java:430)
        at org.apache.avro.generic.GenericDatumReader.readString(GenericDatumReader.java:422)
        at org.apache.avro.generic.GenericDatumReader.readWithoutConversion(GenericDatumReader.java:180)
        at org.apache.avro.generic.GenericDatumReader.read(GenericDatumReader.java:152)
        at org.apache.avro.generic.GenericDatumReader.readField(GenericDatumReader.java:240)
        at org.apache.avro.generic.GenericDatumReader.readRecord(GenericDatumReader.java:230)
        at org.apache.avro.generic.GenericDatumReader.readWithoutConversion(GenericDatumReader.java:174)
        at org.apache.avro.generic.GenericDatumReader.read(GenericDatumReader.java:152)
        at org.apache.avro.generic.GenericDatumReader.read(GenericDatumReader.java:144)
        at io.confluent.kafka.formatter.AvroMessageReader.jsonToAvro(AvroMessageReader.java:213)
        at io.confluent.kafka.formatter.AvroMessageReader.readMessage(AvroMessageReader.java:180)
        at kafka.tools.ConsoleProducer$.main(ConsoleProducer.scala:54)
        at kafka.tools.ConsoleProducer.main(ConsoleProducer.scala)

【结论】通过mysql binlog测试null值效果

参考资料

• Linux 环境下安装Maven https://www.cnblogs.com/jimmy-muyuan/p/7895933.html
• Maven常用命令 https://www.cnblogs.com/wkrbky/p/6352188.html
• Git 提交代码和更新代码 https://blog.csdn.net/Snow_loveLife/article/details/80519998
• kafka avro producer console exceptions https://github.com/Landoop/stream-reactor/issues/148
• Kafka Connect can’t find connector https://stackoverflow.com/questions/53412622/kafka-connect-cant-find-connector
• Failed to find any class that implements Connector https://github.com/DataReply/kafka-connect-mongodb/issues/23