ElasticSearch入门

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1.概述

Elasticsearch是一个基于Lucene（java）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,区别于solr的webservice。

2.安装、启动

jdk1.8(最低)、ElasticSearch客户端、界面工具（Kibana）

2.1 ES客户端

官网地址 https://www.elastic.co/cn/downloads/

• windows下 解压即可使用
• 启动 elasticsearch-7.7.0\bin\elasticsearch.bat 访问地址 localhost:9200

#跨域配置  elasticsearch-7.7.0\config\elasticsearch.yml  增加如下代码
http.cors.enabled: true
http.cors.allow-origin: "*"

2.2 ES可视化工具 ES Head

官网地址 https://github.com/mobz/elasticsearch-head

#启动需要nodejs环境 启动命令   	访问地址  localhost:9100
cd D:\sde\elasticsearch\elasticsearch-head-master
npm install
npm run start

2.3 ES可视化工具 Kibana

官网地址 https://www.elastic.co/cn/downloads/

• windows下 解压即可使用
• 启动 kibana-7.7.1-windows-x86_64\bin 访问地址 localhost:5601

#汉化 kibana-7.7.1-windows-x86_64\config\kibana.yml   增加如下代码
i18n.locale: "zh-CN"

3. IK分词器

官网地址 https://github.com/medcl/elasticsearch-analysis-ik/releases

• 解压到 D:\sde\elasticsearch\elasticsearch-7.7.0\plugins\analysis-ik 目录没有新建analysis-ik 目录名称不重要，随意起

• 检查是否加载分词器

cd D:\sde\elasticsearch\elasticsearch-7.7.0\bin
elasticsearch-plugin list

• 算法 ik_smart(最少切分) ik_max_word（最细粒度切分） 及用kibana校验 默认keywork standard

GET _analyze
{
  "analyzer": "ik_max_word",
  "text": ["美国民主党"]
}

GET _analyze
{
"analyzer": "ik_smart",
"text": ["美国民主党"]
}

• 扩充字典（人名、网络流行语）

<!--elasticsearch-7.7.0\plugins\analysis-ik\config\IKAnalyzer.cfg.xml   可定义自己的字典文件.dic 后缀-->
<entry key="ext_dict">xxx.dic</entry>

4. Kibana 基本语法 API

4.1 新建

#创建空库
PUT /test2
{
    
}

#创建索引 及 规定字段类型
PUT /test3
{
  "mappings": {
    "properties": {
      "name":{
        "type": "text"
      },
      "age":{
        "type": "integer"
      },
      "birth":{
        "type": "date"
      }
    }
  }
}

#创建数据
PUT /wanghl/_doc/2
{
  "name":"花木兰",
  "age":67,
  "tags":["战士","上单","女"]
}

4.2 删除

#删除索引
DELETE test2
#删除文档
DELETE test1/_doc/3

4.3修改

#修改文档
POST /test1/_update/4
{
   "doc":{
     "name":"红桃A"
   }
}

4.4 查询

#获取索引库
GET test3

#获取文档by文档id
GET wanghl/_doc/2

#根据属性查询  简写
GET wanghl/_search?q=name:李

#构建式查询   
#_source    字段过滤   不写默认 select  *
# from  size   分页
GET /wanghl/_search
{
  "query": {
    "match": {
      "tags": "男"
    }
  },
  "_source": ["name","tags"], 
  "from":0,
  "size":1
}

#多条件查询   must 相当于 and     should 相当于 or     
GET wanghl/_search
{
  "query": {
    "bool": {
      "must": [
        {
          "match": {
            "tags": "男 下路"
          }
        }
      ],
      "must_not": [
        {
          "match": {
            "age": "3"
          }
        }
      ]
    }
  }
}

# 查询过滤  +  高亮显示
GET wanghl/_search
{
  "query": {
    "bool": {
      "must": [
        {
          "match": {
            "tags": "男"
          }
        }
      ] ,
      "filter": [
        {
          "range": {
            "age": {
              "gte": 10,
              "lte": 200
            }
          }
        }
      ]  
    }
  },
  "highlight": {
    "pre_tags": "<font>",
    "post_tags": "</font>", 
    "fields": {
      "tags": {}
    }
  }
}

5 SpringBoot集成 ES

1. pom文件添加依赖

<dependency>
   <groupId>org.springframework.boot</groupId>
   <artifactId>spring-boot-starter-data-elasticsearch</artifactId>
</dependency>

2. 注册ES client对象

package com.nesc.esapi.config;

import org.apache.http.HttpHost;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

/**
 * 定义高版本ES实例对象
 * @author wanghl
 * @date 2020/7/17 9:23
 **/
@Configuration
public class ElasticSearchClientConfig {

    @Bean
    public RestHighLevelClient restHighLevelClient() {
        RestHighLevelClient client = new RestHighLevelClient(
                RestClient.builder(
                        new HttpHost("127.0.0.1", 9200, "http")
                )
        );
        return client;
    }
}

3. Junit测试代码

package com.nesc.esapi;

import com.alibaba.fastjson.JSONObject;
import com.nesc.esapi.domain.User;
import lombok.SneakyThrows;
import org.elasticsearch.action.admin.indices.delete.DeleteIndexRequest;
import org.elasticsearch.action.bulk.BulkRequest;
import org.elasticsearch.action.delete.DeleteRequest;
import org.elasticsearch.action.delete.DeleteResponse;
import org.elasticsearch.action.get.GetRequest;
import org.elasticsearch.action.get.GetResponse;
import org.elasticsearch.action.index.IndexRequest;
import org.elasticsearch.action.index.IndexResponse;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.action.support.master.AcknowledgedResponse;
import org.elasticsearch.action.update.UpdateRequest;
import org.elasticsearch.action.update.UpdateResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.client.indices.CreateIndexRequest;
import org.elasticsearch.client.indices.CreateIndexResponse;
import org.elasticsearch.client.indices.GetIndexRequest;
import org.elasticsearch.common.xcontent.XContentType;
import org.elasticsearch.index.query.MatchQueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import org.elasticsearch.search.fetch.subphase.FetchSourceContext;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;

import java.io.IOException;
import java.util.ArrayList;

/**
 * ES client api测试
 */
@SpringBootTest
class EsApiApplicationTests {

    @Autowired
    RestHighLevelClient restHighLevelClient;

    /**
     * 新建索引
     * @throws Exception
     */
    @Test
    void testCreateIndex() throws IOException {
        //创建请求
        CreateIndexRequest request = new CreateIndexRequest("testapi");
        CreateIndexResponse createIndexResponse = restHighLevelClient.indices().create(request,RequestOptions.DEFAULT);
    }

    /**
     * 查询索引
     * @throws IOException
     */
    @Test
    void testExistIndex() throws IOException {
        GetIndexRequest request = new GetIndexRequest("testapi");
        boolean exists = restHighLevelClient.indices().exists(request, RequestOptions.DEFAULT);
        System.out.println(exists);
    }

    /**
     * 删除索引
     * @throws IOException
     */
    @Test
    void testDeleteIndex() throws IOException {
        DeleteIndexRequest deleteIndexRequest = new DeleteIndexRequest("testapi");
        AcknowledgedResponse delete = restHighLevelClient.indices().delete(deleteIndexRequest, RequestOptions.DEFAULT);
        System.out.println(delete);
    }

    /**
     * 创建文档
     * @throws IOException
     */
    @Test
    void testCreateDocument() throws IOException {
        IndexRequest indexRequest = new IndexRequest("testapi");
        User user = new User("张飞","射手");
        IndexRequest source = indexRequest.source(JSONObject.toJSONString(user), XContentType.JSON);
        IndexResponse index = restHighLevelClient.index(indexRequest, RequestOptions.DEFAULT);
        System.out.println(index.toString());
    }

    /**
     * 文档是否存在
     * @throws IOException
     */
    @Test
    void testExistDocument() throws IOException {
        //testapi 索引中     是否存在 1 的文档
        GetRequest getRequest = new GetRequest("testapi", "1");
        boolean exists = restHighLevelClient.exists(getRequest, RequestOptions.DEFAULT);
        System.out.println(exists);
    }

    /**
     * 获取文档信息
     * @throws IOException
     */
    @Test
    void testGetDocument() throws IOException {
        GetRequest getRequest = new GetRequest("testapi", "gBd0W3MBYL0QvcF5Z9tv");
        GetResponse documentFields = restHighLevelClient.get(getRequest, RequestOptions.DEFAULT);
        System.out.println(documentFields.getSource());
    }

    /**
     * 获取文档信息
     * @throws IOException
     */
    @Test
    void testUpdatDocument() throws IOException {
        UpdateRequest updateRequest = new UpdateRequest("testapi", "jxeBW3MBYL0QvcF5idvD");
        User user = new User("张飞","坦克");
        updateRequest.doc(JSONObject.toJSONString(user),XContentType.JSON);
        UpdateResponse update = restHighLevelClient.update(updateRequest, RequestOptions.DEFAULT);
        System.out.println(update.status());
    }

    /**
     * 删除文档信息
     * @throws IOException
     */
    @Test
    void testDeleteDocument() throws IOException {
        DeleteRequest deleteRequest = new DeleteRequest("testapi", "jxeBW3MBYL0QvcF5idvD");
        DeleteResponse delete = restHighLevelClient.delete(deleteRequest, RequestOptions.DEFAULT);
        System.out.println(delete.status());
    }

    /**
     * 查询文档
     */
    @Test
    void testSearchDocument() throws IOException {
        SearchRequest searchRequest = new SearchRequest("testapi");
        //匹配字段
        MatchQueryBuilder matchQueryBuilder = QueryBuilders.matchQuery("username", "李白");
        //构建查询器
        searchRequest.source(new SearchSourceBuilder().query(matchQueryBuilder));
        SearchResponse searchResponse = restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT);
        System.out.println(searchResponse.getHits().getTotalHits());
    }
}

ElasticSearch入门（集成SpringBoot）

原文：https://www.cnblogs.com/wanghl1130/p/13354521.html