Hive写入ES时提示httpclient包找不到的问题

在数据计算完成后，有部分数据会有导入ES的需求，最常用也是最简单的就是使用hive-elasticsearch的映射表来实现，可参考将Hive表与ElasticSearch关联。在ElasticSearch7.8.0与CDH5.9中可以正常将数据由Hive写入ElasticSearch。但是更换为CDH6.3以后，会出现如下错误：

2020-11-04 19:10:19,363 INFO [IPC Server handler 6 on 36328] org.apache.hadoop.mapred.TaskAttemptListenerImpl: Diagnostics report from attempt_1604387526070_2011_m_000000_0: Error: java.lang.RuntimeException: java.lang.NoClassDefFoundError: org/apache/commons/httpclient/protocol/ProtocolSocketFactory
	at org.apache.hadoop.hive.ql.exec.mr.ExecMapper.map(ExecMapper.java:157)
	at org.apache.hadoop.mapred.MapRunner.run(MapRunner.java:54)
	at org.apache.hadoop.mapred.MapTask.runOldMapper(MapTask.java:465)
	at org.apache.hadoop.mapred.MapTask.run(MapTask.java:349)
	at org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:174)
	at java.security.AccessController.doPrivileged(Native Method)
	at javax.security.auth.Subject.doAs(Subject.java:422)
	at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1875)
	at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:168)
Caused by: java.lang.NoClassDefFoundError: org/apache/commons/httpclient/protocol/ProtocolSocketFactory
	at org.elasticsearch.hadoop.rest.commonshttp.CommonsHttpTransportFactory.create(CommonsHttpTransportFactory.java:40)
	at org.elasticsearch.hadoop.rest.NetworkClient.selectNextNode(NetworkClient.java:99)
	at org.elasticsearch.hadoop.rest.NetworkClient.(NetworkClient.java:82)
	at org.elasticsearch.hadoop.rest.NetworkClient.(NetworkClient.java:58)
	at org.elasticsearch.hadoop.rest.RestClient.(RestClient.java:101)
	at org.elasticsearch.hadoop.rest.InitializationUtils.discoverNodesIfNeeded(InitializationUtils.java:89)
	at org.elasticsearch.hadoop.rest.RestService.createWriter(RestService.java:585)
	at org.elasticsearch.hadoop.mr.EsOutputFormat$EsRecordWriter.init(EsOutputFormat.java:175)
	at org.elasticsearch.hadoop.hive.EsHiveOutputFormat$EsHiveRecordWriter.write(EsHiveOutputFormat.java:59)
	at org.apache.hadoop.hive.ql.exec.FileSinkOperator.process(FileSinkOperator.java:769)
	at org.apache.hadoop.hive.ql.exec.Operator.forward(Operator.java:882)
	at org.apache.hadoop.hive.ql.exec.SelectOperator.process(SelectOperator.java:95)
	at org.apache.hadoop.hive.ql.exec.Operator.forward(Operator.java:882)
	at org.apache.hadoop.hive.ql.exec.TableScanOperator.process(TableScanOperator.java:130)
	at org.apache.hadoop.hive.ql.exec.MapOperator$MapOpCtx.forward(MapOperator.java:146)
	at org.apache.hadoop.hive.ql.exec.MapOperator.process(MapOperator.java:484)
	at org.apache.hadoop.hive.ql.exec.mr.ExecMapper.map(ExecMapper.java:148)
	... 8 more
Caused by: java.lang.ClassNotFoundException: org.apache.commons.httpclient.protocol.ProtocolSocketFactory
	at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
	at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:349)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
	... 25 more

很是费解，乍一看就是httpclient的锅，于是我将httpclient-4.5.12.jar添加到hive中，发现错误依旧，后来查阅资料才发现这里要加入的httpclient是commons-httpclient-3.1.jar，于是将其添加后执行成功。

1.在hive shell中添加

这种方式是session级别的，仅对当前会话有用，无需重启hiveserver2服务。

## 本地jar
add jar /opt/expansion/jars/elasticsearch-hadoop-hive-7.8.0.jar;
add jar /opt/expansion/jars/commons-httpclient-3.1.jar;
## hdfs的jar包
add jar  hdfs://nameservice1/expansion/jars/elasticsearch-hadoop-hive-7.8.0.jar;
add jar  hdfs://nameservice1/expansion/jars/commons-httpclient-3.1.jar;

2.启动hive shell时添加

这种方式同样也是session级别

hive -hiveconf hive.aux.jars.path=/opt/expansion/jars/elasticsearch-hadoop-hive-7.8.0.jar

3.在hive-site.xml中添加

这种方式是服务级别的，在hive shell和hiveserver2中均生效，需要重启hiveserver2服务。
编辑hive-site.xml

<property>
  <name>hive.aux.jars.path</name>
  <value>/opt/hive-auxlib/elasticsearch-hadoop-hive-7.8.0.jar</value>
</property>

通常都推荐第三种方式，将其放在hive.aux.jars.path下使用。
commons-httpclient-3.1.jar通常CDH都会自带，具体路径为：

/opt/cloudera/parcels/CDH/jars/commons-httpclient-3.1.jar