Elasticsearch RestclientApi基础用法

Elasticsearch RestclientApi基础用法

索引

初始化

添加依赖

<dependency><groupId>org.elasticsearch.client</groupId><artifactId>elasticsearch-rest-high-level-client</artifactId>
</dependency>

创建链接

package com.hmall.item.es;import org.apache.http.HttpHost;
import org.elasticsearch.action.admin.indices.delete.DeleteIndexRequest;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.client.indices.CreateIndexRequest;
import org.elasticsearch.client.indices.GetIndexRequest;
import org.elasticsearch.common.xcontent.XContentType;
import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;import java.io.IOException;import static org.junit.jupiter.api.Assertions.*;/*** @ Author qwh* @ Date 2024/6/19 8:51*/class itemApplicationTest {private RestHighLevelClient client;//创建链接@BeforeEachvoid setup(){this.client = new RestHighLevelClient(RestClient.builder(HttpHost.create("http://192.168.70.145:9200")));}//测试链接@Testvoid testConnect(){System.out.println(client);}//关闭链接@AfterEachvoid destroy() throws IOException {this.client.close();}}

创建索引库

    @Testvoid CreateIndex() throws IOException {//1CreateIndexRequest request = new CreateIndexRequest("items");//2request.source(MAPPING_TEMPLATE, XContentType.JSON);//3client.indices().create(request, RequestOptions.DEFAULT);}static final String MAPPING_TEMPLATE = "{\n" +"  \"mappings\": {\n" +"    \"properties\": {\n" +"      \"id\": {\n" +"        \"type\": \"keyword\"\n" +"      },\n" +"      \"name\":{\n" +"        \"type\": \"text\",\n" +"        \"analyzer\": \"ik_max_word\"\n" +"      },\n" +"      \"price\":{\n" +"        \"type\": \"integer\"\n" +"      },\n" +"      \"stock\":{\n" +"        \"type\": \"integer\"\n" +"      },\n" +"      \"image\":{\n" +"        \"type\": \"keyword\",\n" +"        \"index\": false\n" +"      },\n" +"      \"category\":{\n" +"        \"type\": \"keyword\"\n" +"      },\n" +"      \"brand\":{\n" +"        \"type\": \"keyword\"\n" +"      },\n" +"      \"sold\":{\n" +"        \"type\": \"integer\"\n" +"      },\n" +"      \"commentCount\":{\n" +"        \"type\": \"integer\"\n" +"      },\n" +"      \"isAD\":{\n" +"        \"type\": \"boolean\"\n" +"      },\n" +"      \"updateTime\":{\n" +"        \"type\": \"date\"\n" +"      }\n" +"    }\n" +"  }\n" +"}";

删除索引库

    //删除索引库@Testvoid DeleteIndex() throws IOException {//创建请求对象DeleteIndexRequest items = new DeleteIndexRequest("items");//发送请求client.indices().delete(items,RequestOptions.DEFAULT);}

判断索引库是否存在

    @Testvoid GetIndex() throws IOException {//发送请求GetIndexRequest items = new GetIndexRequest("items");boolean exists = client.indices().exists(items, RequestOptions.DEFAULT);System.out.println(exists ? "索引库已经存在" : "索引不存在");}

文档

新增文档

1. 实体类

package com.hmall.item.domain.po;import io.swagger.annotations.ApiModel;
import io.swagger.annotations.ApiModelProperty;
import lombok.Data;import java.time.LocalDateTime;@Data
@ApiModel(description = "索引库实体")
public class ItemDoc{@ApiModelProperty("商品id")private String id;@ApiModelProperty("商品名称")private String name;@ApiModelProperty("价格（分）")private Integer price;@ApiModelProperty("商品图片")private String image;@ApiModelProperty("类目名称")private String category;@ApiModelProperty("品牌名称")private String brand;@ApiModelProperty("销量")private Integer sold;@ApiModelProperty("评论数")private Integer commentCount;@ApiModelProperty("是否是推广广告，true/false")private Boolean isAD;@ApiModelProperty("更新时间")private LocalDateTime updateTime;
}

2. api语法

POST /{索引库名}/_doc/1
{"name": "Jack","age": 21
}    

3. java

• 1）创建Request对象，这里是IndexRequest，因为添加文档就是创建倒排索引的过程
• 2）准备请求参数，本例中就是Json文档
• 3）发送请求

package com.hmall.item.es;import cn.hutool.core.bean.BeanUtil;
import cn.hutool.json.JSONUtil;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.hmall.common.utils.CollUtils;
import com.hmall.item.domain.po.Item;
import com.hmall.item.domain.po.ItemDoc;
import com.hmall.item.service.IItemService;
import lombok.extern.slf4j.Slf4j;
import org.apache.http.HttpHost;
import org.elasticsearch.action.bulk.BulkRequest;
import org.elasticsearch.action.delete.DeleteRequest;
import org.elasticsearch.action.get.GetRequest;
import org.elasticsearch.action.get.GetResponse;
import org.elasticsearch.action.index.IndexRequest;
import org.elasticsearch.action.update.UpdateRequest;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.common.xcontent.XContentType;
import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.BeforeEach;
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.List;/*** @ Author qwh* @ Date 2024/6/19 9:29*/
@Slf4j
@SpringBootTest(properties = "spring.profiles.active=local")
public class itemDocTest {private RestHighLevelClient client;@Autowiredprivate IItemService iItemService;@BeforeEachvoid setup(){client = new RestHighLevelClient(RestClient.builder(HttpHost.create("http://192.168.70.145:9200")));}@Test //添加文档void addDocument() throws IOException {//根据id查询item 添加到esItem item = iItemService.getById(100002644680L);//转换为文档类型ItemDoc itemDoc = BeanUtil.copyProperties(item, ItemDoc.class);//将文档类型转换为jsonString doc = JSONUtil.toJsonStr(itemDoc);System.out.println(doc.toString());// 1.准备Request对象IndexRequest request = new IndexRequest("items").id(itemDoc.getId());// 2.准备Json文档request.source(doc, XContentType.JSON);// 3.发送请求client.index(request, RequestOptions.DEFAULT);}@AfterEachvoid destroy() throws IOException {this.client.close();}
}

查询文档

1. api

GET /{索引库名}/_doc/{id}

2. java

• 1）准备Request对象。这次是查询，所以是GetRequest
• 2）发送请求，得到结果。因为是查询，这里调用client.get()方法
• 3）解析结果，就是对JSON做反序列化

    @Testvoid GetDocument() throws IOException {GetRequest request = new GetRequest("items").id("100002644680");//发送请求GetResponse response = client.get(request, RequestOptions.DEFAULT);//获取相应结果String json = response.getSourceAsString();ItemDoc itemDoc = JSONUtil.toBean(json, ItemDoc.class);System.out.println("itemDoc"+itemDoc);}

删除文档

1. api

DELETE /{索引库}/_doc/{id}

2. java

• 1）准备Request对象，因为是删除，这次是DeleteRequest对象。要指定索引库名和id
• 2）准备参数，无参，直接省略
• 3）发送请求。因为是删除，所以是client.delete()方法

    @Testvoid deleteDocument() throws IOException {//准备request 参数 索引库名 文档idDeleteRequest request = new DeleteRequest("items", "100002644680");client.delete(request,RequestOptions.DEFAULT);}

修改文档

• 全量修改：本质是先根据id删除，再新增
• 局部修改：修改文档中的指定字段值

1. api 局部修改

POST /{索引库名}/_update/{id}
{"doc": {"字段名": "字段值","字段名": "字段值"}
}

2. java

• 1）准备Request对象。这次是修改，所以是UpdateRequest
• 2）准备参数。也就是JSON文档，里面包含要修改的字段
• 3）更新文档。这里调用client.update()方法

    //修改文档@Testvoid updateDocument() throws IOException {//requestUpdateRequest request = new UpdateRequest("items", "100002644680");//修改内容request.doc("price",99999,"commentCount",1);//发送请求client.update(request,RequestOptions.DEFAULT);}

批量导入

1. java

• 创建Request，但这次用的是BulkRequest
• 准备请求参数
• 发送请求，这次要用到client.bulk()方法

//批量导入
@Test
void loadItemDocs() throws IOException {
//分页查询
int curPage = 1;
int size = 1000;
while (true){Page<Item> page = iItemService.lambdaQuery().eq(Item::getStatus, 1).page(new Page<>(curPage, size));//f非空校验List<Item> items = page.getRecords();if (CollUtils.isEmpty(items)) {return;}log.info("加载第{}页数据共{}条",curPage,items.size());//创建requestBulkRequest request = new BulkRequest("items");//准备参数for (Item item : items) {ItemDoc itemDoc = BeanUtil.copyProperties(item, ItemDoc.class);request.add(new IndexRequest().id(itemDoc.getId()).source(JSONUtil.toJsonStr(itemDoc),XContentType.JSON));}//发送请求client.bulk(request,RequestOptions.DEFAULT);curPage++;
}
}

文档操作的基本步骤：

• 初始化RestHighLevelClient
• 创建XxxRequest。
  • XXX是Index、Get、Update、Delete、Bulk
• 准备参数（Index、Update、Bulk时需要）
• 发送请求。
  • 调用RestHighLevelClient#.xxx()方法，xxx是index、get、update、delete、bulk
• 解析结果（Get时需要）