04-HighLevelAPI入门，这些客户端的本质就是

八、HighLevelAPI

8.1、RestAPI介绍&项目导入

8.1.1、RestAPI介绍

• ES官方提供了各种不同语言的客户端，用来操作ES。这些客户端的本质就是组装DSL语句，通过http请求发送给ES
• 官方文档地址
  • https://www.elastic.co/guide/en/elasticsearch/client/index.html
• 其中的Java Rest Client又包括两种
  • Java Low Level Rest Client
  • Java High Level Rest Client

本次学习的是HighLevel版本

8.1.2、项目导入

有需要的可以直接联系本人

①、数据库数据导入

• 导入自定义的数据即可；

②、创建初始工程

• 初始工程创建成功后，目录结构如下所示

  • 其中HotelDoc后续会说到

• 配置application.yml

  • 在spring层级下添加es的服务端路径配置

  •   elasticsearch:
        rest:
          uris:
            - http://192.168.222.135:9200
    

• 导入相关依赖

  • <?xml version="1.0" encoding="UTF-8"?>
    <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
        <modelVersion>4.0.0</modelVersion>
        <parent>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-parent</artifactId>
            <version>2.3.8.RELEASE</version>
            <relativePath/> <!-- lookup parent from repository -->
        </parent>
        <groupId>com.coolman.hotel</groupId>
        <artifactId>hotel-demo</artifactId>
        <name>hotel-demo</name>
        <description>Demo project for Spring Boot</description>
        <properties>
            <java.version>1.8</java.version>
        </properties>
        <dependencies>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-web</artifactId>
            </dependency>
            <dependency>
                <groupId>com.baomidou</groupId>
                <artifactId>mybatis-plus-boot-starter</artifactId>
                <version>3.1.1</version>
            </dependency>
            <dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
                <version>8.0.27</version>
                <scope>runtime</scope>
            </dependency>
            <dependency>
                <groupId>org.projectlombok</groupId>
                <artifactId>lombok</artifactId>
                <optional>true</optional>
            </dependency>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-test</artifactId>
                <scope>test</scope>
            </dependency>
    		<dependency>
                <groupId>org.apache.commons</groupId>
                <artifactId>commons-lang3</artifactId>
            </dependency>
    
            <!--es的RestAPI依赖-->
            <dependency>
                <groupId>org.elasticsearch.client</groupId>
                <artifactId>elasticsearch-rest-high-level-client</artifactId>
            </dependency>
        </dependencies>
    
        <build>
            <plugins>
                <plugin>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-maven-plugin</artifactId>
                    <configuration>
                        <excludes>
                            <exclude>
                                <groupId>org.projectlombok</groupId>
                                <artifactId>lombok</artifactId>
                            </exclude>
                        </excludes>
                    </configuration>
                </plugin>
            </plugins>
        </build>
    
    </project>
    
    

• 编写测试类，验证是否可以正常连接

  • package com.coolman.hotel.test;
    
    import lombok.extern.slf4j.Slf4j;
    import org.elasticsearch.client.RestHighLevelClient;
    import org.junit.jupiter.api.Test;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.boot.test.context.SpringBootTest;
    
    @SpringBootTest
    @Slf4j
    public class TestConnectES {
    
        @Autowired
        private RestHighLevelClient restHighLevelClient;
    
        @Test
        public void testConnect() {
          log.info(restHighLevelClient + "");
        }
    }
    
    

8.2、创建索引

• 代码如下所示

  •     /**
         * 创建索引测试
         */
        @Test
        public void testCreateIndex() throws IOException {
            // 1. 获取索引操作对象
            IndicesClient indicesClient = restHighLevelClient.indices();
    
            // 2. 创建索引对象
            CreateIndexRequest request = new CreateIndexRequest("hotel");// 相当于DSL语句的 PUT hotel 请求，但是还没执行
    
            // 3. 执行操作
            CreateIndexResponse response = indicesClient.create(request, RequestOptions.DEFAULT);
    
            // 4. 获取结果
            log.info(response.isAcknowledged() + "");
    
        }
    

• 运行结果如下所示

• Kibana验证

8.3、添加映射

• 代码如下所示

  • 因为创建映射需要DSL语句，所以先在kibana编写如下语句

    • DELETE hotel
      
      GET hotel/_mapping
      
      # 分析hotel索引库的映射结构
      # index属性：是否建立索引，默认值true，如果该字段不用查询，则设置false
      # copy_to: 把指定字段的值拷贝到另一个字段上
      PUT hotel
      {
        "mappings": {
          "properties": {
            "id": {
              "type": "keyword"
            },
            "name": {
              "type": "text",
              "analyzer": "ik_smart",
              "copy_to": "all"
            },
            "address": {
              "type": "text",
              "analyzer": "ik_smart"
            },
            "price": {
              "type": "integer"
            },
            "score": {
              "type": "integer"
            },
            "brand": {
              "type": "keyword",
              "copy_to": "all"
            },
            "city": {
              "type": "keyword"
            },
            "starName": {
              "type": "keyword"
            },
            "business": {
              "type": "keyword",
              "copy_to": "all"
            },
            "location": {
              "type": "geo_point"
            },
            "pic": {
              "type": "keyword",
              "index": false
            },
            "isAD": {
              "type": "boolean"
            },
            "all": {
              "type": "text",
              "analyzer": "ik_smart"
            }
          }
        }
      }
      

  • 创建成功后，再删除，将mappings中的字段复制到Java代码中

  •     /**
         * 添加映射测试
         */
        @Test
        public void testAddMapping() throws IOException {
            // 1. 创建索引操作对象
            IndicesClient indicesClient = restHighLevelClient.indices();
    
            // 2. 创建索引
            CreateIndexRequest request = new CreateIndexRequest("hotel");
    
            // 3. 定义mapping语句
            String mapping = "{\n" +
                    "    \"properties\": {\n" +
                    "      \"id\": {\n" +
                    "        \"type\": \"keyword\"\n" +
                    "      },\n" +
                    "      \"name\": {\n" +
                    "        \"type\": \"text\",\n" +
                    "        \"analyzer\": \"ik_smart\",\n" +
                    "        \"copy_to\": \"all\"\n" +
                    "      },\n" +
                    "      \"address\": {\n" +
                    "        \"type\": \"text\",\n" +
                    "        \"analyzer\": \"ik_smart\"\n" +
                    "      },\n" +
                    "      \"price\": {\n" +
                    "        \"type\": \"integer\"\n" +
                    "      },\n" +
                    "      \"score\": {\n" +
                    "        \"type\": \"integer\"\n" +
                    "      },\n" +
                    "      \"brand\": {\n" +
                    "        \"type\": \"keyword\",\n" +
                    "        \"copy_to\": \"all\"\n" +
                    "      },\n" +
                    "      \"city\": {\n" +
                    "        \"type\": \"keyword\"\n" +
                    "      },\n" +
                    "      \"starName\": {\n" +
                    "        \"type\": \"keyword\"\n" +
                    "      },\n" +
                    "      \"business\": {\n" +
                    "        \"type\": \"keyword\",\n" +
                    "        \"copy_to\": \"all\"\n" +
                    "      },\n" +
                    "      \"location\": {\n" +
                    "        \"type\": \"geo_point\"\n" +
                    "      },\n" +
                    "      \"pic\": {\n" +
                    "        \"type\": \"keyword\",\n" +
                    "        \"index\": false\n" +
                    "      },\n" +
                    "      \"isAD\": {\n" +
                    "        \"type\": \"boolean\"\n" +
                    "      },\n" +
                    "      \"all\": {\n" +
                    "        \"type\": \"text\",\n" +
                    "        \"analyzer\": \"ik_smart\"\n" +
                    "      }\n" +
                    "    }\n" +
                    "  }";
    
            request.mapping(mapping, XContentType.JSON);    // 设置mappings字段，并指定其内容为json格式
    
            // 4. 执行操作
            CreateIndexResponse response = indicesClient.create(request, RequestOptions.DEFAULT);
    
            // 5. 获取结果
            log.info(response.isAcknowledged() + "");
    
        }
    

  • ​

• 运行结果如下所示

• Kibana验证

8.4、删除索引

• 代码如下所示

  •     /**
         * 删除索引测试
         */
        @Test
        public void testDeleteIndex() throws IOException {
            // 1. 获取索引操作对象
            IndicesClient indicesClient = restHighLevelClient.indices();
            
            // 2. 获取索引对象
            DeleteIndexRequest request = new DeleteIndexRequest("hotel");   // DELETE hotel
    
            // 3. 执行操作
            AcknowledgedResponse response = indicesClient.delete(request, RequestOptions.DEFAULT);
    
            // 4. 获取结果
            log.info("" + response.isAcknowledged());
        }
    

• 比较简单，自行验证即可

8.5、添加文档

• 代码如下所示

  •     /**
         * 添加文档测试
         */
    // Jackson
        private ObjectMapper objectMapper = new ObjectMapper();
        @Test
        public void testAddDocument() throws IOException {
            // 先获取 指定的 hotel数据
            Hotel hotel = hotelMapper.selectById(36934);
            HotelDoc hotelDoc = new HotelDoc(hotel);
    
            // 1. 创建请求对象
            IndexRequest request = new IndexRequest("hotel").id(hotelDoc.getId().toString());
    
            // 2. 填充文档内容
            String json = objectMapper.writeValueAsString(hotelDoc);
            request.source(json, XContentType.JSON);
    
            // 3. 执行请求体对象
            IndexResponse response = restHighLevelClient.index(request, RequestOptions.DEFAULT);
    
            // 4. 获取结果
            log.info(response.getId() + "");
        }
    

• Kibana验证

8.6、修改、查询、删除文档

8.6.1、修改文档

修改文档和添加文档操作一样，需要注意的是修改文档必须是已经存在的ID

• 代码如下所示

  •     /**
         * 修改文档
         */
        @Test
        public void testUpdateDocument() throws IOException {
            // 1. 先获取 指定的 hotel 数据
            Hotel hotel = hotelMapper.selectById(36934L);
            HotelDoc hotelDoc = new HotelDoc(hotel);
    
            // 2. 修改数据，如价格
            hotelDoc.setPrice(1999999999);
    
            // 3. 将 hotelDoc 对象转换为 JSON格式的数据
            String json = objectMapper.writeValueAsString(hotelDoc);
    
            // 4. 创建请求对象
            IndexRequest request = new IndexRequest("hotel").id(hotelDoc.getId().toString());
            request.source(json, XContentType.JSON);
    
            // 5. 执行操作
            IndexResponse response = restHighLevelClient.index(request, RequestOptions.DEFAULT);
    
            log.info(response.getId());
        }
    

• Kibana验证

8.6.2、查询文档

• 代码如下所示

  •     /**
         * 查询文档
         */
        @Test
        public void testSearchDocument() throws IOException {
            Long id = 36934L;
            // 1. 创建请求
            GetRequest request = new GetRequest("hotel").id(id.toString());
    
            // 2. 执行请求
            GetResponse response = restHighLevelClient.get(request, RequestOptions.DEFAULT);
    
            // 3. 取出结果
            String hotelDocJson = response.getSourceAsString();
    
            HotelDoc hotelDoc = objectMapper.readValue(hotelDocJson, HotelDoc.class);
    
            log.info(hotelDoc.toString());
        }
    

• 运行结果如下所示

8.6.3、删除文档

• 代码如下所示

  •     /**
         * 删除文档
         */
        @Test
        public void testDeleteDocument() throws IOException {
            Long id = 36934L;
            // 1. 创建请求
            DeleteRequest request = new DeleteRequest("hotel").id(id.toString());
    
            // 2. 执行请求
            DeleteResponse response = restHighLevelClient.delete(request, RequestOptions.DEFAULT);
    
            log.info(response.getId());
    
        }
    

• Kibana验证

8.7、批量添加

• Bulk批量操作是将文档的增删改查一些列操作，通过一次请求全都做完。减少网络传输次数

• 应用场景

  • ES索引库数据初始化的时候，可以将数据库的数据查询出来通过批量操作导入到索引库中

• 代码如下所示

  •     /**
         * 批量添加文档
         */
        @Test
        public void testBatchAddDocument() throws IOException {
            // 1. 获取需要导入的数据
            List<Hotel> hotelList = hotelMapper.selectList(null);
    
            if(CollectionUtils.isNotEmpty(hotelList)) {
                // 2. 创建批量操作请求对象
                BulkRequest bulkRequest = new BulkRequest();
    
                // 4. 获取文档映射的对象数据
                for (Hotel hotel : hotelList) {
                    HotelDoc hotelDoc = new HotelDoc(hotel);
    
                    // 5. 创建请求对象
                    IndexRequest request = new IndexRequest("hotel").id(hotelDoc.getId().toString());;
    
                    // 6. 填充内容
                    String json = objectMapper.writeValueAsString(hotelDoc);
                    request.source(json, XContentType.JSON);
    
                    // 7. 将数据添加到批量操作对象中
                    bulkRequest.add(request);
                }
                // 8. 一次性执行批量操作
                BulkResponse response = restHighLevelClient.bulk(bulkRequest, RequestOptions.DEFAULT);
                log.info(response.status().toString());
            }
        }
    

• 运行结果如下所示

• Kibana验证