ElasticSearch - SpringBoot整合ES实现文档的增删改操作

https://www.elastic.co/guide/en/elasticsearch/reference/current/search-your-data.html
https://www.elastic.co/guide/cn/elasticsearch/guide/current/_retrieving_a_document.html

1. ElasticSearch和kibana的安装和配置

① 下载地址：https://www.elastic.co/cn/downloads/past-releases/elasticsearch-7-4-2

② 修改elasticsearch.yml文件：

 cluster.name: my-applicationpath.data: D:/install/elasticsearch-7.4.2-windows-x86_64/elasticsearch-7.4.2/datapath.logs: D:/install/elasticsearch-7.4.2-windows-x86_64/elasticsearch-7.4.2/logs

③ 配置环境变量：D:\install\elasticsearch-7.4.2-windows-x86_64\elasticsearch-7.4.2\bin

④ 下载ik分词器：https://github.com/medcl/elasticsearch-analysis-ik/releases?after=v7.4.2

⑤ 解压ik分词器，必须解压到D:\install\elasticsearch-7.4.2-windows-x86_64\elasticsearch-7.4.2\plugins\ik目录下

⑥ 点击elasticsearch.bat启动elasticsearch服务，并访问：localhsot:9200

⑦ kibana下载地址：https://www.elastic.co/cn/downloads/past-releases/kibana-7-4-2

⑧ 修改kibana.yml文件（不必须）：

 server.port: 5601server.host: "localhost"elasticsearch.hosts: ["http://localhost:9200"]i18n.locale: "zh-CN"

⑨ 点击kibana.bat启动kibana服务（一定要先启动es）：

⑦ kibana下载地址：https://www.elastic.co/cn/downloads/past-releases/kibana-7-4-2

⑧ 修改kibana.yml文件（不必须）：

 server.port: 5601server.host: "localhost"elasticsearch.hosts: ["http://localhost:9200"]i18n.locale: "zh-CN"

⑨ 点击kibana.bat启动kibana服务（一定要先启动es）

⑩ 访问localhost:5601

2. SpringBoot 项目环境搭建

1、创建项目：ElasticSearch和SpringBoot的版本一定要对应，否则会报各种错误

<?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><!-- 这里我的springboot的版本使用是2.3.2 --><version>2.3.2.RELEASE</version><relativePath/> <!-- lookup parent from repository --></parent><groupId>com.xiao</groupId><artifactId>estest</artifactId><version>0.0.1-SNAPSHOT</version><name>estest</name><description>Demo project for Spring Boot</description><properties><java.version>1.8</java.version><!-- 这里必须要填写，因为springboot2.3.2默认的elasticsearch版本为7.6.2,我们使用的是7.4.2，不更改会产生版本不兼容等问题 --><elasticsearch.version>7.4.2</elasticsearch.version></properties><dependencies><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><!-- 这里我使用的是elasticsearch的high-level-client 版本要和你的elasticsearch版本对应--><dependency><groupId>org.elasticsearch.client</groupId><artifactId>elasticsearch-rest-high-level-client</artifactId><version>7.4.2</version></dependency><!--lombok--><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>cn.hutool</groupId><artifactId>hutool-core</artifactId><version>5.6.5</version></dependency><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><version>1.16.10</version><scope>provided</scope></dependency><dependency><groupId>com.alibaba</groupId><artifactId>fastjson</artifactId><version>1.2.76</version></dependency><dependency><groupId>junit</groupId><artifactId>junit</artifactId><version>4.12</version><scope>test</scope></dependency></dependencies><build><plugins><plugin><groupId>org.springframework.boot</groupId><artifactId>spring-boot-maven-plugin</artifactId></plugin></plugins></build></project>

2、创建一个配置类，用于配置Elasticsearch的集群信息：

@Configuration
public class ElasticSearchConfig {@Beanpublic RestHighLevelClient restHighLevelClient(){RestClientBuilder builder = RestClient.builder(new HttpHost("localhost",9200,"http"));RestHighLevelClient client = new RestHighLevelClient(builder);return client;}
}

3. 创建索引

1、在项目的resource/elasticsearch目录下创建一个文件mapping.json文件定义索引的映射：

{"properties": {"categoryId": {"type": "keyword"},"content": {"type": "text","analyzer": "ik_max_word","search_analyzer": "ik_smart"},"name": {"analyzer": "ik_max_word","search_analyzer": "ik_smart","type": "text"},"creator": {"type": "keyword"},"editor": {"type": "keyword"},"from": {"type": "keyword"},"id": {"type": "keyword"},"tags": {"type": "keyword"},"updateTime": {"type": "date","format": "yyyy-MM-dd HH:mm:ss||epoch_millis"},"createTime": {"type": "date","format": "yyyy-MM-dd HH:mm:ss||epoch_millis"}}
}

2、项目启动的时候判断knowledge索引是否存在并根据定义的映射创建该索引：

@Slf4j
@Service
public class ElasticSearchImpl {private static final String KNOWLEDGE_INDEX = "knowledge";@Autowiredprivate RestHighLevelClient restHighLevelClient;@PostConstructpublic void init(){try {// 查询索引GetIndexRequest request = new GetIndexRequest(KNOWLEDGE_INDEX);boolean exist = restHighLevelClient.indices().exists(request, RequestOptions.DEFAULT);if (!exist) {CreateIndexRequest createIndexRequest = new CreateIndexRequest("knowledge");ClassPathResource mappingResource = new ClassPathResource("elasticsearch/mapping.json");byte[] bytes = FileCopyUtils.copyToByteArray(mappingResource.getInputStream());String json = new String(bytes, StandardCharsets.UTF_8);createIndexRequest.mapping(json, XContentType.JSON);restHighLevelClient.indices().create(createIndexRequest, RequestOptions.DEFAULT);}} catch (IOException e) {log.error("failed to create index mapping:", e);throw new CommonException("elasticsearch.create.index.failed");}}
}

3、启动项目，在kibana客户端查看索引是否创建成功：

GET /knowledge/_search 

{"took" : 0,"timed_out" : false,"_shards" : {"total" : 1,"successful" : 1,"skipped" : 0,"failed" : 0},"hits" : {"total" : {"value" : 0,"relation" : "eq"},"max_score" : null,"hits" : [ ]}
}

说明索引添加成功。

4. 索引文档

1、定义一个映射对象：

@Data
public class Doc {private String id;private String name;private String content;private String creator;private String editor;private Date createTime;private Date updateTime;
}

2、索引文档：

@Slf4j
@Service
public class ElasticSearchImpl {private static final String KNOWLEDGE_INDEX = "knowledge";@Autowiredprivate RestHighLevelClient restHighLevelClient;public void saveDoc(Doc doc) throws JsonProcessingException {IndexRequest indexRequest = new IndexRequest("knowledge");indexRequest.id(doc.getId());// ES使用 json 文档代表了一个对象String jsonString = new JsonMapper().writeValueAsString(doc);indexRequest.source(jsonString, XContentType.JSON);// ElasticSearch是近实时搜索，刚索引的文档并不是立即对搜索可见，需要手动刷新indexRequest.setRefreshPolicy(WriteRequest.RefreshPolicy.IMMEDIATE);try {restHighLevelClient.index(indexRequest, RequestOptions.DEFAULT);} catch (IOException e) {log.error("failed to add document to elasticsearch,the doc is:{},the exception is {}", doc, e);throw new CommonException("elasticsearch.create.index.failed");}}
}

3、测试索引文档：

@SpringBootTest
@RunWith(SpringRunner.class)
public class BeanLoadServiceTest {@Autowiredprivate ElasticSearchImpl elasticSearchImpl;@Testpublic void testSaveDoc(){// Elasticsearch 是面向文档的，意味着它存储整个对象或文档Doc doc = new Doc();doc.setId("1");doc.setName("茶花女");doc.setContent("这是一本非常好看的小说，有时间的小伙伴可以看一下");doc.setCreator("小仲马");doc.setEditor("小仲马");doc.setCreateTime(new Date());doc.setUpdateTime(new Date());elasticSearchImpl.saveDoc(doc);}
}

4、在kibana客户端查询索引中的文档：

GET /knowledge/_doc/1

{"_index" : "knowledge","_type" : "_doc","_id" : "1","_version" : 1,"_seq_no" : 0,"_primary_term" : 1,"found" : true,"_source" : {"id" : "1","name" : "茶花女","content" : "这是一本非常好看的小说，有时间的小伙伴可以看一下","creator" : "小仲马","editor" : "小仲马","createTime" : 1677229499680,"updateTime" : 1677229499680}
}

5. 更新文档

1、更新文档：

@Slf4j
@Service
public class ElasticSearchImpl {private static final String KNOWLEDGE_INDEX = "knowledge";@Autowiredprivate RestHighLevelClient restHighLevelClient;public void updateDoc(Doc doc) throws JsonProcessingException {UpdateRequest updateRequest = new UpdateRequest(KNOWLEDGE_INDEX, doc.getId());String jsonString = new JsonMapper().writeValueAsString(doc);updateRequest.doc(jsonString, XContentType.JSON);updateRequest.setRefreshPolicy(WriteRequest.RefreshPolicy.IMMEDIATE);try {restHighLevelClient.update(updateRequest, RequestOptions.DEFAULT);} catch (IOException e) {log.error("failed to update document to elasticsearch,the doc is:{},the exception is {}", doc, e);throw new CommonException("elasticsearch.create.index.failed");}}
}

2、测试更新文档：

@SpringBootTest
@RunWith(SpringRunner.class)
public class BeanLoadServiceTest {@Autowiredprivate ElasticSearchImpl elasticSearchImpl;@Testpublic void testUpdateDoc() throws JsonProcessingException {// Elasticsearch 是面向文档的，意味着它存储整个对象或文档Doc doc = new Doc();doc.setId("1");doc.setName("茶花女");doc.setContent("这是一本非常好看的小说，有时间的小伙伴可以看一下");doc.setCreator("大仲马");doc.setEditor("大仲马");doc.setCreateTime(new Date());doc.setUpdateTime(new Date());elasticSearchImpl.saveDoc(doc);}
}

3、在kibana客户端查看索引中的文档：

{"_index" : "knowledge","_type" : "_doc","_id" : "1","_version" : 2,"_seq_no" : 1,"_primary_term" : 1,"found" : true,"_source" : {"id" : "1","name" : "茶花女","content" : "这是一本非常好看的小说，有时间的小伙伴可以看一下","creator" : "大仲马","editor" : "大仲马","createTime" : 1677229755142,"updateTime" : 1677229755142}
}

6. 删除文档

1、删除文档：

@Slf4j
@Service
public class ElasticSearchImpl {private static final String KNOWLEDGE_INDEX = "knowledge";@Autowiredprivate RestHighLevelClient restHighLevelClient;public void deleteDoc(Set<String> ids) {DeleteByQueryRequest deleteByQueryRequest = new DeleteByQueryRequest(KNOWLEDGE_INDEX);deleteByQueryRequest.setQuery(new TermsQueryBuilder("id", ids));deleteByQueryRequest.setRefresh(true);try {restHighLevelClient.deleteByQuery(deleteByQueryRequest, RequestOptions.DEFAULT);} catch (IOException e) {log.error("failed to delete the document in elasticsearch,the doc ids is:{},the exception is {}", ids, e);throw new CommonException("elasticsearch.create.index.failed");}}
}

2、测试删除文档：

@SpringBootTest
@RunWith(SpringRunner.class)
public class BeanLoadServiceTest {@Autowiredprivate ElasticSearchImpl elasticSearchImpl;@Testpublic void testDeleteDoc() throws JsonProcessingException {// Elasticsearch 是面向文档的，意味着它存储整个对象或文档List<String> list = Arrays.asList("1");elasticSearchImpl.deleteDoc(new HashSet<String>(list));}
}

3、在kibana客户端查看删除的文档：

GET /knowledge/_doc/1

{"_index" : "knowledge","_type" : "_doc","_id" : "1","found" : false
}