对mysql、oracle等数据库数据进行同步到ES有三种做法:一个是通过elasticsearch提供的API进行增删改查,一个就是通过中间件进行数据全量、增量的数据同步,另一个是通过收集日志进行同步。 明显通过API增上改查比较麻烦,这里介绍的是利用中间件进行数据同步。 一些配置过程及常见问题介绍,还有插件的比较。
1、介绍
对mysql、oracle等数据库数据进行同步到ES有三种做法:一个是通过elasticsearch提供的API进行增删改查,一个就是通过中间件进行数据全量、增量的数据同步,另一个是通过收集日志进行同步。
明显通过API增上改查比较麻烦,这里介绍的是利用中间件进行数据同步。
2、常用的同步中间件的介绍和对比
(1)elasticsearch-jdbc独立的第三方工具 https://github.com/jprante/elasticsearch-jdbc
(2)elasticsearch-river-mysql https://github.com/scharron/elasticsearch-river-mysql
(3)go-mysql-elasticsearch(国内) https://github.com/siddontang/go-mysql-elasticsearch
都可以完成数据同步;
elasticsearch-jdbc更通用,GitHub活跃度很高;
elasticsearch-river-mysql 自2013年后便不再更新;
go-mysql-elasticsearch仍处理开发不稳定阶段;
elasticsearch-river-jdbc和elasticsearch-river-mysql都不支持对删掉的数据进行同步,go-mysql-elasticsearch希望可以改善这个问题。
总的来说,elasticsearch-jdbc更适合使用,对于删掉的数据可以采用API进行同步,或者在数据中不进行物理删除可以避免该问题的出现。
3、elasticsearch的安装
这里使用的是2.3.2版本,可以到官方网站下载,这里不提供官方地址,或者访问 下载本篇文章所用到的两个安装包。
得到elasticsearch-2.3.2.tar.gz
[zsz@zsz ~]$ tar -zxvf elasticsearch-2.3.2.tar.gz
[zsz@zsz ~]$ mv elasticsearch-2.3.2 /usr/local/elasticsearch-2.3.2
启动elasticsearch服务
[zsz@zsz ~]$./bin/elasticsearch
另外,bin/elasticsearch -d(后台运行);
如何需要修改配置,可以查看/elasticsearch-2.3.2/config/elasticsearch.yml;
查看节点情况:
[zsz@zsz downloads]$ curl 'localhost:9200/_cat/nodes?v'
host ip heap.percent ram.percent load node.role master name
127.0.0.1 127.0.0.1 12 79 0.18 d * node-1
查看索引,当前为无索引:
[zsz@zsz downloads]$ curl 'localhost:9200/_cat/indices?v'
health status index pri rep docs.count docs.deleted store.size pri.store.size
创建索引:
[zsz@zsz downloads]$ curl -XPUT 'localhost:9200/customer?pretty'
{
"acknowledged" : true
}
[zsz@zsz downloads]$ curl 'localhost:9200/_cat/indices?v'
health status index pri rep docs.count docs.deleted store.size pri.store.size
yellow open customer 5 1 0 0 650b 650b
增加索引并搜索:
[zsz@zsz downloads]$ curl -XPUT 'localhost:9200/customer/external/1?pretty' -d '
> {
> "name": "John Doe"
> }'
{
"_index" : "customer",
"_type" : "external",
"_id" : "1",
"_version" : 1,
"_shards" : {
"total" : 2,
"successful" : 1,
"failed" : 0
},
"created" : true
}
可以看到,一个新的文档在customer索引和external类型中被成功创建。文档也有一个内部id 1, 这个id是在增加索引的时候指定的。下面来检索这个记录:
[zsz@zsz downloads]$ curl -XGET 'localhost:9200/customer/external/1?pretty'
{
"_index" : "customer",
"_type" : "external",
"_id" : "1",
"_version" : 1,
"found" : true,
"_source" : {
"name" : "John Doe"
}
}
[zsz@zsz downloads]$ curl 'localhost:9200/customer/_search?q=John'
{"took":2,"timed_out":false,"_shards":{"total":5,"successful":5,"failed":0},"hits":{"total":1,"max_score":0.19178301,"hits":[{"_index":"customer","_type":"external","_id":"1","_score":0.19178301,"_source":
{
"name": "John Doe"
}}]}}
更新这个索引:
[zsz@zsz downloads]$ curl -XPOST 'localhost:9200/customer/external/1/_update?pretty' -d '
> {
> "doc": { "name": "Jane Doe Haha" }
> }'
{
"_index" : "customer",
"_type" : "external",
"_id" : "1",
"_version" : 2,
"_shards" : {
"total" : 2,
"successful" : 1,
"failed" : 0
}
}
[zsz@zsz downloads]$ curl -XGET 'localhost:9200/customer/external/1?pretty'
{
"_index" : "customer",
"_type" : "external",
"_id" : "1",
"_version" : 2,
"found" : true,
"_source" : {
"name" : "Jane Doe Haha"
}
}
删除该索引:
[zsz@zsz downloads]$ curl -XDELETE 'localhost:9200/customer/external/1?pretty'
{
"found" : true,
"_index" : "customer",
"_type" : "external",
"_id" : "1",
"_version" : 3,
"_shards" : {
"total" : 2,
"successful" : 1,
"failed" : 0
}
}
[zsz@zsz downloads]$ curl -XGET 'localhost:9200/customer/external/1?pretty'
{
"_index" : "customer",
"_type" : "external",
"_id" : "1",
"found" : false
}
ES必要的插件
必要的Head、kibana、IK(中文分词)、graph等插件的详细安装和使用。
ES对外接口
JAVA API接口
http://www.ibm.com/developerworks/library/j-use-elasticsearch-java-apps/index.html
RESTful API接口
常见的增、删、改、查操作实现:
ES遇到常见问题
https://discuss.elastic.co/, http://elasticsearch.cn/
3、elasticsearch-jdbc的安装配置
需要的安装包:elasticsearch-jdbc-2.3.2.0-dist.zip,它是与elasticsearch-2.3.2.tar.gz相对应的,其他版本会出错。
下载地址:
[zsz@zsz downloads]$ vi /etc/profile
#增加elasticsearch-jdbc插件的环境变量
export JDBC_IMPORTER_HOME=/home/downloads/elasticsearch-jdbc-2.3.2.0
[zsz@zsz downloads]$ source /etc/profile
创建同步:
[zsz@zsz downloads]$ mkdir /odbc_es
[zsz@zsz downloads]$ cd /odbc_es
[zsz@zsz odbc_es]$ vi mysql_import_es.sh
#!/bin/sh
bin=$JDBC_IMPORTER_HOME/bin
lib=$JDBC_IMPORTER_HOME/lib
echo '{
"type" : "jdbc",
"jdbc": {
"elasticsearch.autodiscover":true,
"elasticsearch.cluster":"elasticsearch",##需要与/elasticsearch-2.3.2/config/elasticsearch.yml的配置对应
"url":"jdbc:mysql://***:3306/**",
"user":"**",
"password":"**",
"sql":"select * from news",
"elasticsearch" : {
"host" : "127.0.0.1",
"port" : 9300
},
"index" : "myindex",
"type" : "mytype"
}
}'| java \
-cp "${lib}/*" \
-Dlog4j.configurationFile=${bin}/log4j2.xml \
org.xbib.tools.Runner \
org.xbib.tools.JDBCImporter
##根据个人项目情况填写以上的地址
运行数据同步脚本mysql_import_es.sh:
[zsz@zsz odbc_es]$ ./mysql_import_es.sh
查看是否同步成功:
[zsz@zsz odbc_es]$ curl 'localhost:9200/_cat/indices?v'
health status index pri rep docs.count docs.deleted store.size pri.store.size
yellow open myindex 5 1 163 0 146.5kb 146.5kb
yellow open customer 5 1 0 0 795b 795b
[zsz@zsz odbc_es]$ curl -XGET 'http://127.0.0.1:9200/myindex/mytype/_search?pretty'
{
"took" : 9,
"timed_out" : false,
"_shards" : {
"total" : 5,
"successful" : 5,
"failed" : 0
}
......
说明同步数据成功。
问题与解决:
1、提示no cluster nodes available, check settings
解决:请查看/elasticsearch-2.3.2/config/elasticsearch.yml。一般都是该文件配置错误造成的,比如单机模式的,配置了node节点,或者cluster.name错误。