【Spring Boot 2.0学习之旅-12】搜索框架ElasticSearch介绍和整合SpringBoot

好了，下面我们看一下今天的主角 ElasticsearchRepository 他是怎样的吧。

这说明什么？

• 用法和JPA一样；
• 再这他除了有CRUD的基本功能之外，还有分页和排序。

本次使用的Java客户端是官方新推出的RestHighLevelClient，使用Http连接查询结果。Java REST Client

    4.0.0
    
        org.springframework.boot
        spring-boot-starter-parent
        2.5.7
         
    
    com.lcz
    spring_demo18
    0.0.1-SNAPSHOT
    spring_demo18
    Demo project for Spring Boot
    
        1.8
    
    
        
            org.springframework.boot
            spring-boot-starter-web
        
        
            org.springframework.boot
            spring-boot-starter-data-elasticsearch
        
        
            com.alibaba
            fastjson
            1.2.47
        


        
            org.projectlombok
            lombok
            true
        
        
            org.springframework.boot
            spring-boot-starter-test
            test
        
    

    
        
            
                org.springframework.boot
                spring-boot-maven-plugin
                
                    
                        
                            org.projectlombok
                            lombok
                        
                    
                
            
        
    

地址

spring.data.elasticsearch.cluster-name=elasticsearch
spring.data.elasticsearch.cluster-nodes=127.0.0.1:9300
spring.data.elasticsearch.repositories.enabled=true

spring:
  elasticsearch:
    rest:
      uris: 47.114.142.39:9200
      read-timeout: 30s
      connection-timeout: 5s

但是上述方法 过期了。

根据Spring Data Elasticsearch的Spring 文档：

将TransportClient被弃用的Elasticsearch 7，并将在被移除Elasticsearch 8。TransportClient只要在使用的 Elasticsearch 版本中可用，Spring Data Elasticsearch 将支持 它，但自版本以来已弃用使用它的类4.0

注意： 这意味着 Spring 团队也会弃用 Elasticsearch 7 支持的旧属性。

现在，Spring 团队推荐开发者使用RestHighLevelClient它现在是Elasticsearch. 它是 的直接替代品，TransportClient因为它接受并返回相同的请求/响应对象。

代码演示如下：

@Configuration
public class ClientConfig {
    @Bean("client")
    public RestHighLevelClient getRestHighLevelClient(){
        RestHighLevelClient client = new RestHighLevelClient(
                //es服务的地址和端口，如果有多个es(es集群)可以链式编程，添加es地址
                RestClient.builder(new HttpHost("127.0.0.1",9200,"http"))
        );
        return client;
    }
}

创建ES客户端配置类，注意使用@Bean时需要指定bean的名字，因为ES默认会自动初始化客户端对象，否则在使用@Autowired依赖注入时,会有多个同一类型的bean，导入注入失败。

创建实体类，在插入文档时需要.

关于@document注解

package com.lcz.spring_demo18.domain;

import lombok.*;



public class User {
    private String name;
    private Integer age;
    private String address;

    public User(){

    }
    public User(String name, Integer age, String address) {
        this.name = name;
        this.age = age;
        this.address = address;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Integer getAge() {
        return age;
    }

    public void setAge(Integer age) {
        this.age = age;
    }

    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address = address;
    }
}

@document代表定义这个是文档, 其中indexName就是索引库的名字必须标注

@Id是标识文档的唯一id

@Field 就是字段了, 其中type为KeyWord代表这个字段不分词, analyzer是存数据的时候用的分词器

索引和文档的CRUD单元测试

package com.lcz.spring_demo18.controller;


import com.alibaba.fastjson.JSON;
import com.lcz.spring_demo18.domain.User;
import org.elasticsearch.action.admin.indices.delete.DeleteIndexRequest;
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.support.master.AcknowledgedResponse;
import org.elasticsearch.action.support.replication.ReplicationResponse;
import org.elasticsearch.client.indices.GetIndexRequest;
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.action.update.UpdateRequest;
import org.elasticsearch.client.indices.CreateIndexResponse;
import org.elasticsearch.common.xcontent.XContentType;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;

import java.util.Map;


@RestController
public class EsController {

    @Autowired
    private RestHighLevelClient client;

    private Logger log = LoggerFactory.getLogger(this.getClass());
    
    @PutMapping("/create_index")
    public Object createIndex() throws Exception{
        CreateIndexRequest createIndexRequest = new CreateIndexRequest("index_one");
        CreateIndexResponse createIndexResponse = client.indices().create(createIndexRequest, RequestOptions.DEFAULT);
        log.info(createIndexResponse.index());
        log.info(Boolean.toString(createIndexResponse.isAcknowledged()));
        log.info(Boolean.toString(createIndexResponse.isShardsAcknowledged()));
        return createIndexResponse;
    }

    
    @GetMapping("get_index")
    public void getIndex() throws Exception{
        GetIndexRequest getIndexRequest = new GetIndexRequest("index_one");
        boolean flag = client.indices().exists(getIndexRequest,RequestOptions.DEFAULT);
        if(flag){
            log.info("index_one索引库存在");
        }else{
            log.info("index_one索引库不存在");
        }
    }

    
    @DeleteMapping("delete_index")
    public void deleteIndex() throws Exception{
        DeleteIndexRequest deleteIndexRequest = new DeleteIndexRequest("index_one");
        AcknowledgedResponse acknowledgedResponse = client.indices().delete(deleteIndexRequest,RequestOptions.DEFAULT);
        //判断  true表示删除成功
        if(acknowledgedResponse.isAcknowledged()){
            log.info("删除成功");
        }else{
            log.info("删除失败");
        }
    }


    
    @PutMapping("/put_doc")
    public void createdocument() throws Exception{
        User user = new User("张文文",20,"山西省太原市");
        //需要操作哪个索引库
        IndexRequest indexRequest = new IndexRequest("index_one");
        indexRequest.id("2");
        //将对象转换为json字符串存储
        indexRequest.source(JSON.toJSONString(user), XContentType.JSON);
        IndexResponse indexResponse = client.index(indexRequest,RequestOptions.DEFAULT);
        log.info("------对应kibana中的API请求返回结果");
        log.info(indexResponse.getIndex());
        log.info(indexResponse.getId());
        log.info(String.valueOf(indexResponse.getVersion()));
        log.info(indexResponse.getResult().getLowercase());
        ReplicationResponse.ShardInfo shardInfo = indexResponse.getShardInfo();
        log.info(String.valueOf(shardInfo.getSuccessful()));
        indexResponse.status();
    }


    
    @GetMapping("/get_doc")
    public void getdocument() throws Exception{

        //查询所有时，进行遍历，的每一个都是map,将map放到list里，最后再通过list展示所有

        GetRequest getRequest = new GetRequest("index_one","1");
        if(client.exists(getRequest,RequestOptions.DEFAULT)){
            GetResponse getResponse = client.get(getRequest,RequestOptions.DEFAULT);
            //返回的是单个文档的数据，key为字段名称，value为字段的值
            Map map = getResponse.getSource();
            log.info(String.valueOf(map.get("name")));
            log.info(String.valueOf(map.get("age")));
            log.info(String.valueOf(map.get("address")));
        }else{
            log.info("当前文档不存在");
        }
    }


    
    @PostMapping("update_doc")
    public void updatedocument() throws Exception{
        UpdateRequest updateRequest = new UpdateRequest("index_one","1");
        User user = new User();
        user.setAge(10000);
        updateRequest.doc(JSON.toJSONString(user),XContentType.JSON);
        UpdateResponse updateResponse = client.update(updateRequest,RequestOptions.DEFAULT);
        log.info("更新结果:" + updateResponse.getResult().getLowercase());
    }


    
    @DeleteMapping("/delete_doc")
    public void deletedocument() throws Exception{
        DeleteRequest deleteRequest = new DeleteRequest("index_one","2");
        DeleteResponse deleteResponse = client.delete(deleteRequest,RequestOptions.DEFAULT);
        log.info("删除结果:" + deleteResponse.status().name());
        log.info("删除结果:" + deleteResponse.getResult().getLowercase());
    }

}

创建索引库

 @PutMapping("/create_index")
    public Object createIndex() throws Exception{
        CreateIndexRequest createIndexRequest = new CreateIndexRequest("index_one");
        CreateIndexResponse createIndexResponse = client.indices().create(createIndexRequest, RequestOptions.DEFAULT);
        log.info(createIndexResponse.index());
        log.info(Boolean.toString(createIndexResponse.isAcknowledged()));
        log.info(Boolean.toString(createIndexResponse.isShardsAcknowledged()));
        return createIndexResponse;
    }

判断索引库是否存在

 @GetMapping("get_index")
    public void getIndex() throws Exception{
        GetIndexRequest getIndexRequest = new GetIndexRequest("index_one");
        boolean flag = client.indices().exists(getIndexRequest,RequestOptions.DEFAULT);
        if(flag){
            log.info("index_one索引库存在");
        }else{
            log.info("index_one索引库不存在");
        }
    }

删除索引

@DeleteMapping("delete_index")
    public void deleteIndex() throws Exception{
        DeleteIndexRequest deleteIndexRequest = new DeleteIndexRequest("index_one");
        AcknowledgedResponse acknowledgedResponse = client.indices().delete(deleteIndexRequest,RequestOptions.DEFAULT);
        //判断  true表示删除成功
        if(acknowledgedResponse.isAcknowledged()){
            log.info("删除成功");
        }else{
            log.info("删除失败");
        }
    }

创建文档

 @PutMapping("/put_doc")
    public void createdocument() throws Exception{
        User user = new User("吕厂长",20,"山东省济南市");
        //需要操作哪个索引库
        IndexRequest indexRequest = new IndexRequest("index_one");
        indexRequest.id("1");
        //将对象转换为json字符串存储
        indexRequest.source(JSON.toJSONString(user), XContentType.JSON);
        IndexResponse indexResponse = client.index(indexRequest,RequestOptions.DEFAULT);
        log.info("------对应kibana中的API请求返回结果");
        log.info(indexResponse.getIndex());
        log.info(indexResponse.getId());
        log.info(String.valueOf(indexResponse.getVersion()));
        log.info(indexResponse.getResult().getLowercase());
        ReplicationResponse.ShardInfo shardInfo = indexResponse.getShardInfo();
        log.info(String.valueOf(shardInfo.getSuccessful()));
        indexResponse.status();
    }

获取文档

@GetMapping("/get_doc")
    public void getdocument() throws Exception{

        //查询所有时，进行遍历，的每一个都是map,将map放到list里，最后再通过list展示所有

        GetRequest getRequest = new GetRequest("index_one","1");
        if(client.exists(getRequest,RequestOptions.DEFAULT)){
            GetResponse getResponse = client.get(getRequest,RequestOptions.DEFAULT);
            //返回的是单个文档的数据，key为字段名称，value为字段的值
            Map map = getResponse.getSource();
            log.info(String.valueOf(map.get("name")));
            log.info(String.valueOf(map.get("age")));
            log.info(String.valueOf(map.get("address")));
        }else{
            log.info("当前文档不存在");
        }
    }

更新文档

@PostMapping("update_doc")
    public void updatedocument() throws Exception{
        UpdateRequest updateRequest = new UpdateRequest("index_one","1");
        User user = new User();
        user.setAge(18);
        updateRequest.doc(JSON.toJSONString(user),XContentType.JSON);
        UpdateResponse updateResponse = client.update(updateRequest,RequestOptions.DEFAULT);
        log.info("更新结果:" + updateResponse.getResult().getLowercase());
    }

删除文档

 @DeleteMapping("/delete_doc")
    public void deletedocument() throws Exception{
        DeleteRequest deleteRequest = new DeleteRequest("index_one","2");
        DeleteResponse deleteResponse = client.delete(deleteRequest,RequestOptions.DEFAULT);
        log.info("删除结果:" + deleteResponse.status().name());
        log.info("删除结果:" + deleteResponse.getResult().getLowercase());
    }

可视化的elasticsearch head