Elasticsearch
ElasticSearch是一个基于Lucene的搜索服务器。它提供了一个分布式多用户能力的全文搜索引擎,基于RESTful web接口。Elasticsearch是用Java开发的,并作为Apache许可条款下的开放源码发布,是当前流行的企业级搜索引擎。设计用于云计算中,能够达到实时搜索,稳定,可靠,快速,安装使用方便。
Elasticsearch Reference
参考文档:
https://www.elastic.co/guide/en/elasticsearch/reference/current/index.html
ES安装
下载elasticsearch-2.2.0.tar.gz,解压,执行/bin/elasticsearch;
访问地址:http://node1:9200
安装插件 head
执行bin/plugin install mobz/elasticsearch-head
访问地址:http://node1:9200/_plugin/head
如果用root用户执行启动脚本会提示:
Exception in thread "main" java.lang.RuntimeException: don't run elasticsearch as root.
创建elasticsearch用户执行
adduser –U elasticsearch
然后以 elasticsearch用户登录,启动程序。
集群部署
部署三台机器,部署程序,然后修改配置文件 config/elasticsearch.yml
配置:
cluster.name: my-application node.name: node1 discovery.zen.ping.multicast.enabled: false discovery.zen.ping_timeout: 120s client.transport.ping_timeout: 60s discovery.zen.ping.unicast.hosts: ["node1","node2", "node3"]
集群名字cluster.name相同才能组成一个集群,修改node.name对应的主机名。
防止脑裂配置
discovery.zen.minimum_master_nodes=2
Curl
通过curl操作Elasticsearch数据:
curl -XPUT ‘http://node1:9200/index1/’ -d ‘传输的数据’
-X指定http请求方法:HEAD, PUT, GET, PST, DELETE
-d 指定传输的数据
–GET:获取对象的当前状态;
–PUT:改变对象的状态; 幂等
–POST:创建对象;
–DELETE:删除对象; 幂等
–HEAD:获取头信息。
Elasticsearch与关系型数据库的对比
Database | Index |
Table | Type |
Row | Document |
Column | Field |
创建Index
curl -XPUT 'http://node1:9200/test/'
创建Type
curl -XPOST http://node1:9200/test/emp/ -d '{"name" : "John"}' 自动创建id,也可以自己指定id
curl -XPUT http://node1:9200/test/emp/1 -d '{"name" : "Tom"}' 需要指定id
查询
curl -XGET http://node1:9200/test/emp/1
{"_index":"test","_type":"emp","_id":"1","_version":2,"found":true,"_source":{"name" : "Jim"}}
curl -XGET http://node1:9200/test/emp/1?pretty
{
"_index" : "test",
"_type" : "emp",
"_id" : "1",
"_version" : 2,
"found" : true,
"_source" : {
"name" : "Jim"
}
}
pretty 格式化结果,更好看
查询带报文头
curl -i http://node1:9200/test/emp/1?pretty
HTTP/1.1 200 OK
Content-Type: application/json; charset=UTF-8
Content-Length: 134
{
"_index" : "test",
"_type" : "emp",
"_id" : "1",
"_version" : 2,
"found" : true,
"_source" : {
"name" : "Jim"
}
}
查询_source
curl -XGET http://node1:9200/test/emp/1/_source
{"name" : "Jim"}
查询指定field的信息
curl -XGET http://node1:9200/test/emp/1?_source=name
查询type信息
curl -XGET http://node1:9200/test/emp/_search?pretty
{
"took" : 7,
"timed_out" : false,
"_shards" : {
"total" : 5,
"successful" : 5,
"failed" : 0
},
"hits" : {
"total" : 3,
"max_score" : 1.0,
"hits" : [ {
"_index" : "test",
"_type" : "emp",
"_id" : "AVYw5zrHBTthl-73fXCK",
"_score" : 1.0,
"_source" : {
"name" : "John"
}
}, {
"_index" : "test",
"_type" : "emp",
"_id" : "2",
"_score" : 1.0,
"_source" : {
"name" : "John"
}
}, {
"_index" : "test",
"_type" : "emp",
"_id" : "1",
"_score" : 1.0,
"_source" : {
"name" : "Jim"
}
} ]
}
}
查询指定条件数据
curl -XGET http://node1:9200/test/emp/_search?q=name:Jim
Domain Specific Language DSL 查询
curl -XGET http://node1:9200/test/emp/_search?pretty -d \
'{"query":
{"match":
{"name":"Jim"}
}
}'
获取多个文档
curl -XGET http://node1:9200/_mget?pretty -d \
'{"docs":[{"_index":"test","_type":"emp","_id":1},{"_index":"test","_type":"emp","_id":2}]
}'
curl -XGET http://node1:9200/test/emp/_mget?pretty -d \
'{"ids":["1","2"]
}'
检查文档是否存在,只返回报文头
curl -i -XHEAD http://node1:9200/test/emp/1?pretty
更新字段信息
curl -XPUT http://node1:9200/test/emp/1?pretty -d \
'{"name":"Tom",}'
局部更新(增加first_name字段) 只能用POST
curl -XPOST http://node1:9200/test/emp/1/_update -d '{"doc":{"first_name":"Jim"}}'
删除文档
curl -XDELETE http://node1:9200/test/emp/1
指定id
查询设置 副本数量,分片数量
curl -XGET http://node1:9200/test/_settings?pretty
{
"test" : {
"settings" : {
"index" : {
"creation_date" : "1469698597831",
"uuid" : "VFew5vmlQUC3Uieu62w23Q",
"number_of_replicas" : "1",
"number_of_shards" : "5",
"version" : {
"created" : "2020099"
}
}
}
}
}
设置分片及副本数
curl -XPUT http://node1:9200/test/_settings -d'{"settings":{"number_of_shards":3,"number_of_replicas":2}}'
查询mapping信息
curl -XGET http://node1:9200/test/_mapping?pretty
用于修改字段相关属性,如字段类型,是否使用分词器,使用哪种分词器
curl -XPOST http://node1:9200/test/emp/_mapping -d \ '{ "emp": { "properties": { "name" : { "type" : "string", "analyzer" : "standard" } } } }'
解析器
curl -XGET 'http://node1:9200/_analyze?analyzer=standard&pretty=true' -d '很高兴认识你'
使用解析器查看结果
具体说明参考官方文档:https://www.elastic.co/guide/en/elasticsearch/reference/2.2/analyzer.html
Java API
官方文档:
https://www.elastic.co/guide/en/elasticsearch/client/java-api/2.2/index.html
测试demo:
注意:这里使用term时注意使用小写,由于使用了分词器
1 import org.elasticsearch.action.get.GetResponse; 2 import org.elasticsearch.action.index.IndexResponse; 3 import org.elasticsearch.action.search.SearchResponse; 4 import org.elasticsearch.action.search.SearchType; 5 import org.elasticsearch.client.Client; 6 import org.elasticsearch.client.transport.TransportClient; 7 import org.elasticsearch.common.settings.Settings; 8 import org.elasticsearch.common.transport.InetSocketTransportAddress; 9 import org.elasticsearch.common.unit.TimeValue; 10 import org.elasticsearch.common.xcontent.XContentFactory; 11 import org.elasticsearch.index.query.QueryBuilder; 12 import org.elasticsearch.index.query.QueryBuilders; 13 import org.elasticsearch.search.SearchHit; 14 import org.junit.After; 15 import org.junit.Before; 16 import org.junit.Test; 17 18 import java.io.IOException; 19 import java.net.InetAddress; 20 import java.net.UnknownHostException; 21 22 /** 23 * Created by Edward on 2016/7/29. 24 */ 25 public class MyTest { 26 27 public static Client client; 28 29 @Before 30 public void init() throws UnknownHostException { 31 Settings settings = Settings.settingsBuilder() 32 .put("cluster.name", "my-application").build(); 33 client = TransportClient.builder().settings(settings).build() 34 .addTransportAddress(new InetSocketTransportAddress(InetAddress.getByName("node1"), 9300)) 35 .addTransportAddress(new InetSocketTransportAddress(InetAddress.getByName("node2"), 9300)) 36 .addTransportAddress(new InetSocketTransportAddress(InetAddress.getByName("node3"), 9300)); 37 } 38 @After 39 public void closeClient() 40 { 41 client.close(); 42 } 43 44 @Test 45 public void createIndex() throws IOException { 46 //创建索引 47 IndexResponse response = client.prepareIndex("test", "emp", "1") 48 .setSource(XContentFactory.jsonBuilder() 49 .startObject() 50 .field("name", "Tom") 51 .field("age", "21") 52 .field("message", "Elasticsearch") 53 .endObject()) 54 .get(); 55 System.out.println(response); 56 } 57 58 @Test 59 public void queryIndex(){ 60 //获取索引信息 61 GetResponse res = client.prepareGet("test", "emp", "1").get(); 62 System.out.println(res.getSource()); 63 } 64 65 @Test 66 public void search(){ 67 68 SearchResponse response = client.prepareSearch("test") 69 .setTypes("emp") 70 .setSearchType(SearchType.DFS_QUERY_THEN_FETCH) 71 //注意term使用了分词,这里tom使用小写 72 .setQuery(QueryBuilders.termQuery("name", "tom")) // Query 73 //.setPostFilter(QueryBuilders.rangeQuery("age").from(12).to(18)) // Filter 74 //.setFrom(0).setSize(60).setExplain(true) 75 .execute() 76 .actionGet(); 77 System.out.println(response.getHits().getHits().length); 78 //SearchResponse response = client.prepareSearch().execute().actionGet(); 79 System.out.println(response.toString()); 80 } 81 82 83 @Test 84 public void scrollQuery(){ 85 86 //注意由于使用了分词,这里tom使用小写 87 QueryBuilder qb = QueryBuilders.termQuery("name", "tom"); 88 89 SearchResponse scrollResp = client.prepareSearch("test") 90 .setTypes("emp") 91 .setSearchType(SearchType.SCAN) 92 .setScroll(new TimeValue(60000)) 93 .setQuery(qb) 94 .setSize(100).execute().actionGet(); //100 hits per shard will be returned for each scroll 95 //Scroll until no hits are returned 96 while (true) { 97 scrollResp = client.prepareSearchScroll(scrollResp.getScrollId()).setScroll(new TimeValue(60000)).execute().actionGet(); 98 for (SearchHit hit : scrollResp.getHits().getHits()) { 99 //Handle the hit... 100 System.out.println(hit.getSource()); 101 } 102 103 //Break condition: No hits are returned 104 if (scrollResp.getHits().getHits().length == 0) { 105 break; 106 } 107 } 108 } 109 }