elasticsearch-hadoop是一个深度集成Hadoop和ElasticSearch的项目，也是ES官方来维护的一个子项目，通过实现Hadoop和ES之间的输入输出，可以在Hadoop里面对ES集群的数据进行读取和写入，充分发挥Map-Reduce并行处理的优势，为Hadoop数据带来实时搜索的可能。 
项目网址：http://www.elasticsearch.org/overview/hadoop/

运行环境： 
CDH4、ElasticSearch0.90.2

http://www.cloudera.com/content/cloudera-content/cloudera-docs/CDH4/latest/CDH4-Quick-Start/cdh4qs_topic_3_3.html

https://github.com/medcl/elasticsearch-rtf

Hive和ES的互操作： 
#安装，HIVE里面添加ElasticSearch-Hadoop的JAR路径 
#下载hadoop-es jar包,https://download.elasticsearch.org/hadoop/hadoop-latest.zip

#Hive加载的JAR路径为本地路径

[medcl@node- ~]$ ls

elasticsearch-hadoop-1.3..M1.jar

[medcl@node- ~]$ pwd

/home/medcl

[medcl@node- ~]$ hive -hiveconf hive.aux.jars.path=/home/medcl/elasticsearch-hadoop-1.3..M1.jar

Logging initialized using configuration in file:/etc/hive/conf.dist/hive-log4j.properties

Hive history file=/tmp/medcl/hive_job_log_94db3616-e210-4aab-b07b-6fb159e217ec_1758848920.txt

#ElasticSearch集群名为"elasticsearch",和Hadoop在一个机器上

#Hive里面创建一个Table(user)，并使用Hadoop-ElasticSearch关联一个索引（/index/user）,2个字段，id和name

CREATE EXTERNAL TABLE user  (id INT, name STRING,site STRING)

STORED BY 'org.elasticsearch.hadoop.hive.ESStorageHandler'

TBLPROPERTIES('es.resource' = 'index/user/',

              'es.index.auto.create' = 'true')
在medcl用下操作：

CREATE EXTERNAL TABLE user  (id INT, name STRING)

STORED BY 'org.elasticsearch.hadoop.hive.ESStorageHandler'

TBLPROPERTIES('es.resource' = '/index/user/',

              'es.index.auto.create' = 'true');
FAILED: Execution Error, return code 1 from org.apache.hadoop.hive.ql.exec.DDLTask

hive> CREATE EXTERNAL TABLE user  (id INT, name STRING)

    > STORED BY 'org.elasticsearch.hadoop.hive.ESStorageHandler'

    > TBLPROPERTIES('es.resource' = 'medcl/',

    >               'es.index.auto.create' = 'false');

FAILED: Error in metadata: MetaException(message:Got exception: org.apache.hadoop.security.AccessControlException Permission denied: user=medcl, access=WRITE, inode="/user":hdfs:supergroup:drwxr-xr-x

 

#擦，看下权限

[medcl@node- ~]$ hadoop fs -lsr /

lsr: DEPRECATED: Please use 'ls -R' instead.

drwxrwxrwt   - hdfs supergroup           -- : /tmp

drwxr-xr-x   - hdfs supergroup           -- : /user

drwxr-xr-x   - medcl supergroup           -- : /user/medcl

drwxr-xr-x   - medcl supergroup           -- : /user/medcl/input

-rw-r--r--    medcl supergroup     -- : /user/medcl/input/file1.txt

drwxr-xr-x   - medcl supergroup           -- : /user/medcl/lib

-rw-r--r--    medcl supergroup      -- : /user/medcl/lib/elasticsearch-hadoop-1.3..M1.jar

drwxr-xr-x   - hdfs  supergroup           -- : /var

drwxr-xr-x   - hdfs  supergroup           -- : /var/lib

#原来user目录权限是hdfs，ok，切换hdfs，jar也换个hdfs用户可以访问到的位置，就/tmp吧

[root@node- medcl]# cp elasticsearch-hadoop-1.3..M1.jar  /tmp/

[root@node- medcl]# ^C

[root@node- medcl]# sudo -u hdfs hive -hiveconf hive.aux.jars.path=/tmp/elasticsearch-hadoop-1.3..M1.jar

Logging initialized using configuration in file:/etc/hive/conf.dist/hive-log4j.properties

Hive history file=/tmp/hdfs/hive_job_log_bdad4d7a-f929-43d7-a56e-e026fdd7e3b4_1219802521.txt

hive> CREATE EXTERNAL TABLE user  (id INT, name STRING)

    > STORED BY 'org.elasticsearch.hadoop.hive.ESStorageHandler'

    > TBLPROPERTIES('es.resource' = '/index/user/',

    >               'es.index.auto.create' = 'false');

-- ::29.560 GMT Thread[main,,main] java.io.FileNotFoundException: derby.log (Permission denied)

----------------------------------------------------------------

-- ::29.877 GMT:

 Booting Derby version The Apache Software Foundation - Apache Derby - 10.4.2.0 - (): instance a816c00e--fc62-4b5c-000000cec758

on database directory /var/lib/hive/metastore/metastore_db in READ ONLY mode 

Database Class Loader started - derby.database.classpath=''

FAILED: Error in metadata: java.lang.RuntimeException: Unable to instantiate org.apache.hadoop.hive.metastore.HiveMetaStoreClient

FAILED: Execution Error, return code  from org.apache.hadoop.hive.ql.exec.DDLTask

#ok，干掉lock

[root@node- ~]# ls /var/lib/hive/metastore/metastore_db

dbex.lck  db.lck  log  seg0  service.properties  tmp

[root@node- ~]# rm /var/lib/hive/metastore/metastore_db/dbex.lck

rm: remove regular file `/var/lib/hive/metastore/metastore_db/dbex.lck'? y

[root@node- ~]# rm /var/lib/hive/metastore/metastore_db/db.lck

rm: remove regular file `/var/lib/hive/metastore/metastore_db/db.lck'? y



#另外忘记关另外一个hive实例了，难怪呢。

[root@node- tmp]# ps -aux|grep hive

Warning: bad syntax, perhaps a bogus '-'? See /usr/share/doc/procps-3.2./FAQ

root       0.0  0.1    pts/    S+   :   : sudo -u hdfs hive -hiveconf hive.aux.jars.path=/tmp/elasticsearch-hadoop-1.3..M1.jar

hdfs       1.8  5.7   pts/   Sl+  :   : /usr/lib/jvm/java-openjdk/bin/java -Xmx256m -Dhadoop.log.dir=/usr/lib/hadoop/logs -Dhadoop.log.file=hadoop.log -Dhadoop.home.dir=/usr/lib/hadoop -Dhadoop.id.str= -Dhadoop.root.logger=INFO,console -Djava.library.path=/usr/lib/hadoop/lib/native -Dhadoop.policy.file=hadoop-policy.xml -Djava.net.preferIPv4Stack=true -Dhadoop.security.logger=INFO,NullAppender org.apache.hadoop.util.RunJar /usr/lib/hive/lib/hive-cli-0.10.-cdh4.5.0.jar org.apache.hadoop.hive.cli.CliDriver -hiveconf hive.aux.jars.path=/tmp/elasticsearch-hadoop-1.3..M1.jar
 
 
#权限问题

[root@node- tmp]# ll /var/lib/hive/metastore/metastore_db/

total

drwxrwxr-x  medcl medcl  Dec  : log

drwxrwxr-x  medcl medcl  Dec  : seg0

-rw-rw-r--  medcl medcl   Dec  : service.properties

drwxrwxr-x  medcl medcl  Dec  : tmp

[root@node- tmp]# sudo -u hdfs hive -hiveconf hive.aux.jars.path=/tmp/elasticsearch-hadoop-1.3..M1.jar^C

[root@node- tmp]# chmod  /var/lib/hive/metastore/metastore_db/ -R

[root@node- tmp]# sudo -u hdfs hive -hiveconf hive.aux.jars.path=/tmp/elasticsearch-hadoop-1.3..M1.jar

Logging initialized using configuration in file:/etc/hive/conf.dist/hive-log4j.properties

Hive history file=/tmp/hdfs/hive_job_log_d5749cb0-fde0-4da2--c85cf4673885_252074310.txt

hive> show tables;

OK

Time taken: 6.934 seconds

hive> CREATE EXTERNAL TABLE user  (id INT, name STRING)

    > STORED BY 'org.elasticsearch.hadoop.hive.ESStorageHandler'

    > TBLPROPERTIES('es.resource' = '/index/user/',

    >               'es.index.auto.create' = 'true');

OK

Time taken: 1.115 seconds

#ok，创建成功了

hive> show tables;

OK

user

Time taken: 0.15 seconds

hive> 

#权限问题是Hive默认仓库路径造成的，生疏了

[root@node- tmp]# sudo su hdfs

bash-4.1$ hadoop fs -lsr /

lsr: DEPRECATED: Please use 'ls -R' instead.

drwxrwxrwt   - hdfs supergroup           -- : /tmp

drwxr-xr-x   - hdfs supergroup           -- : /user

drwxr-xr-x   - hdfs  supergroup           -- : /user/hive

drwxr-xr-x   - hdfs  supergroup           -- : /user/hive/warehouse

drwxr-xr-x   - hdfs  supergroup           -- : /user/hive/warehouse/user

#好了，开始往HIVE里面倒数据了，先来几行数据

[root@node- tmp]# cat files1.txt

,medcl

,lcdem

,tom

,jack

#传上去

[root@node- tmp]# sudo su hdfs

bash-4.1$ hadoop fs -put files1.txt /tmp/

bash-4.1$ hadoop fs -ls /tmp/

Found  items

-rw-r--r--    hdfs supergroup          -- : /tmp/files1.txt

#加载到Hive里面

hive -hiveconf hive.aux.jars.path=/tmp/elasticsearch-hadoop-1.3..M1.jar

#LOAD DATA LOCAL INPATH '/tmp/files1.txt' OVERWRITE INTO TABLE user_source;

#CREATE EXTERNAL TABLE user_source  (id INT, name STRING);

#不是原始Hive表，还不能直接LOAD

bash-4.1$ hive -hiveconf hive.aux.jars.path=/tmp/elasticsearch-hadoop-1.3..M1.jar

Logging initialized using configuration in file:/etc/hive/conf.dist/hive-log4j.properties

Hive history file=/tmp/hdfs/hive_job_log_a9516f87-6e2d-44db-9d38-18eed77d9dec_1583221137.txt

hive> LOAD DATA LOCAL INPATH '/tmp/files1.txt' OVERWRITE INTO TABLE user;

FAILED: SemanticException [Error ]: A non-native table cannot be used as target for LOAD

hive> CREATE EXTERNAL TABLE user_source  (id INT, name STRING);

OK

Time taken: 1.104 seconds

hive> LOAD DATA LOCAL INPATH '/tmp/files1.txt' OVERWRITE INTO TABLE user_source;

Copying data from file:/tmp/files1.txt

Copying file: file:/tmp/files1.txt

Loading data to table default.user_source

Table default.user_source stats: [num_partitions: , num_files: , num_rows: , total_size: , raw_data_size: ]

OK

Time taken: 0.911 seconds

hive> show tables;

OK

user

user_source

Time taken: 0.226 seconds

#下面这个错误是因为es-hadoop的jar文件没有传到HDFS上面，看来本地和HDFS都要上传，并且路径要一致

hive> select id,name from  user_source;

Total MapReduce jobs =

Launching Job  out of

Number of reduce tasks is set to  since there's no reduce operator

java.io.FileNotFoundException: File does not exist: /tmp/elasticsearch-hadoop-1.3..M1.jar

  at org.apache.hadoop.hdfs.DistributedFileSystem.getFileStatus(DistributedFileSystem.java:)

  at org.apache.hadoop.filecache.DistributedCache.getFileStatus(DistributedCache.java:)

  at org.apache.hadoop.filecache.TrackerDistributedCacheManager.determineTimestamps(TrackerDistributedCacheManager.java:)

  at org.apache.hadoop.filecache.TrackerDistributedCacheManager.determineTimestampsAndCacheVisibilities(TrackerDistributedCacheManager.java:)

  at org.apache.hadoop.mapred.JobClient.copyAndConfigureFiles(JobClient.java:)

  at org.apache.hadoop.mapred.JobClient.copyAndConfigureFiles(JobClient.java:)

  at org.apache.hadoop.mapred.JobClient.access$(JobClient.java:)

  at org.apache.hadoop.mapred.JobClient$.run(JobClient.java:)

  at org.apache.hadoop.mapred.JobClient$.run(JobClient.java:)

  at java.security.AccessController.doPrivileged(Native Method)

  at javax.security.auth.Subject.doAs(Subject.java:)

  at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:)

  at org.apache.hadoop.mapred.JobClient.submitJobInternal(JobClient.java:)

  at org.apache.hadoop.mapred.JobClient.submitJob(JobClient.java:)

  at org.apache.hadoop.hive.ql.exec.ExecDriver.execute(ExecDriver.java:)

  at org.apache.hadoop.hive.ql.exec.MapRedTask.execute(MapRedTask.java:)

  at org.apache.hadoop.hive.ql.exec.Task.executeTask(Task.java:)

  at org.apache.hadoop.hive.ql.exec.TaskRunner.runSequential(TaskRunner.java:)

  at org.apache.hadoop.hive.ql.Driver.launchTask(Driver.java:)

  at org.apache.hadoop.hive.ql.Driver.execute(Driver.java:)

  at org.apache.hadoop.hive.ql.Driver.run(Driver.java:)

  at org.apache.hadoop.hive.ql.Driver.run(Driver.java:)

  at org.apache.hadoop.hive.cli.CliDriver.processLocalCmd(CliDriver.java:)

  at org.apache.hadoop.hive.cli.CliDriver.processCmd(CliDriver.java:)

  at org.apache.hadoop.hive.cli.CliDriver.processLine(CliDriver.java:)

  at org.apache.hadoop.hive.cli.CliDriver.run(CliDriver.java:)

  at org.apache.hadoop.hive.cli.CliDriver.main(CliDriver.java:)

  at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

  at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:)

  at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:)

  at java.lang.reflect.Method.invoke(Method.java:)

  at org.apache.hadoop.util.RunJar.main(RunJar.java:)

Job Submission failed with exception 'java.io.FileNotFoundException(File does not exist: /tmp/elasticsearch-hadoop-1.3.0.M1.jar)'

FAILED: Execution Error, return code  from org.apache.hadoop.hive.ql.exec.MapRedTask

#ok，再看看

bash-4.1$ hadoop fs -put elasticsearch-hadoop-1.3..M1.jar  /tmp/

bash-4.1$ hive -hiveconf hive.aux.jars.path=/tmp/elasticsearch-hadoop-1.3..M1.jar

Logging initialized using configuration in file:/etc/hive/conf.dist/hive-log4j.properties

Hive history file=/tmp/hdfs/hive_job_log_28ea1fbc-dc3b-4e62-9f47-1a88eed30069_1310993479.txt

hive> select id,name from  user_source;

Total MapReduce jobs =

Launching Job  out of

Number of reduce tasks is set to  since there's no reduce operator

Starting Job = job_201312162220_0004, Tracking URL = http://localhost:50030/jobdetails.jsp?jobid=job_201312162220_0004

Kill Command = /usr/lib/hadoop/bin/hadoop job  -kill job_201312162220_0004

Hadoop job information for Stage-: number of mappers: ; number of reducers:

-- ::, Stage- map = %,  reduce = %

-- ::, Stage- map = %,  reduce = %, Cumulative CPU 0.88 sec

-- ::, Stage- map = %,  reduce = %, Cumulative CPU 0.88 sec

-- ::, Stage- map = %,  reduce = %, Cumulative CPU 0.88 sec

-- ::, Stage- map = %,  reduce = %, Cumulative CPU 0.88 sec

-- ::, Stage- map = %,  reduce = %, Cumulative CPU 0.88 sec

MapReduce Total cumulative CPU time:  msec

Ended Job = job_201312162220_0004

MapReduce Jobs Launched:

Job : Map:    Cumulative CPU: 0.88 sec   HDFS Read:  HDFS Write:  SUCCESS

Total MapReduce CPU Time Spent:  msec

OK

NULL    NULL

NULL    NULL

NULL    NULL

NULL    NULL

Time taken: 25.999 seconds

#慢，数据怎么是空的，建成外表了(EXTERNAL)，没有设置默认的分隔符,好纠结

hive> drop table user_source;

OK

Time taken: 0.649 seconds

hive> CREATE TABLE user_source  (id INT, name STRING) ROW FORMAT DELIMITED FIELDS TERMINATED BY ',';

OK

Time taken: 0.109 seconds

hive> LOAD DATA LOCAL INPATH '/tmp/files1.txt' INTO TABLE user_source;

Copying data from file:/tmp/files1.txt

Copying file: file:/tmp/files1.txt

Loading data to table default.user_source

Table default.user_source stats: [num_partitions: , num_files: , num_rows: , total_size: , raw_data_size: ]

OK

Time taken: 0.348 seconds

hive> select * from  user_source;

OK

    medcl

    lcdem

    tom

    jack

Time taken: 0.155 seconds

#源表现在有了，导入到ES所在的表里面去

hive> INSERT OVERWRITE TABLE user

    > SELECT s.id, s.name FROM user_source s;

Total MapReduce jobs =

Launching Job  out of

Number of reduce tasks is set to  since there's no reduce operator

Starting Job = job_201312162220_0005, Tracking URL = http://localhost:50030/jobdetails.jsp?jobid=job_201312162220_0005

Kill Command = /usr/lib/hadoop/bin/hadoop job  -kill job_201312162220_0005

Hadoop job information for Stage-: number of mappers: ; number of reducers:

-- ::, Stage- map = %,  reduce = %

-- ::, Stage- map = %,  reduce = %, Cumulative CPU 1.16 sec

-- ::, Stage- map = %,  reduce = %, Cumulative CPU 1.16 sec

-- ::, Stage- map = %,  reduce = %, Cumulative CPU 1.16 sec

-- ::, Stage- map = %,  reduce = %, Cumulative CPU 1.16 sec

-- ::, Stage- map = %,  reduce = %, Cumulative CPU 1.16 sec

MapReduce Total cumulative CPU time:  seconds  msec

Ended Job = job_201312162220_0005

 Rows loaded to user

MapReduce Jobs Launched:

Job : Map:    Cumulative CPU: 1.16 sec   HDFS Read:  HDFS Write:  SUCCESS

Total MapReduce CPU Time Spent:  seconds  msec

OK

Time taken: 21.849 seconds

hive> select * from user;

OK

Failed with exception java.io.IOException:java.lang.IllegalStateException: [GET] on [/index/user/&search_type=scan&scroll=10m&size=&preference=_shards:;_only_node:MP7Zl3owTRm8O2V6cWvOSg] failed; server[http://10.0.2.15:9200] returned [{"_index":"index","_type":"user","_id":"&search_type=scan&scroll=10m&size=50&preference=_shards:4;_only_node:MP7Zl3owTRm8O2V6cWvOSg","exists":false}]

Time taken: 0.387 seconds

#可以看出来hadoop-elasticsearch翻译出来的查询语句好像有问题！不过elasticsearch里面已经有数据了，反正暂时不需要用hive来执行查询，先官方发个issue吧。

#ES查询结果

bash-4.1$ curl localhost:/index/user/_search?q=*&pretty=true

[]

bash-4.1$ {"took":,"timed_out":false,"_shards":{"total":,"successful":,"failed":},"hits":{"total":,"max_score":1.0,"hits":[{"_index":"index","_type":"user","_id":"3x4bEcriRvS6AHkX2Sb7UA","_score":1.0, "_source" : {"id":,"name":"lcdem"}},{"_index":"index","_type":"user","_id":"_3rGVWhaTSCixYxRzBUSLQ","_score":1.0, "_source" : {"id":,"name":"jack"}},{"_index":"index","_type":"user","_id":"T-Q_icjgR8ehsH3IV-twWw","_score":1.0, "_source" : {"id":,"name":"medcl"}},{"_index":"index","_type":"user","_id":"Vdz0sryBT5u0e9hfoMY8Tg","_score":1.0, "_source" : {"id":,"name":"tom"}}]}}

#接下来试试大量数据bulk导入的性能，是不是真的做到data locality。




elasticsearch-hadoop下载地址：https://github.com/elastic/elasticsearch-hadoop




												


											
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