springboot使用elasticsearch的客户端操作eslaticsearch

一 ES客户端

　　ES提供多种不同的客户端：

　　　　1、TransportClient

　　　　ES提供的传统客户端，官方计划8.0版本删除此客户端。

　　　　2、RestClient

　　　　RestClient是官方推荐使用的，它包括两种：Java Low Level REST Client和 Java High Level REST Client。

　　　　ES在6.0之后提供 Java High Level REST Client，两种客户端官方更推荐使用 Java High Level REST Client，不过当前它还处于完善中，有些功能还没有。

　　　　3 spring-data-elasticsearch

　　　　这个是基于TransportClient开发的，虽然在有些版本还是可以用，但是更新对应版本太慢了

采用 Java High Level REST Client，如果它有不支持的功能，则使用Java Low Level REST Client。

二整合

　　首先是pom.xml

　　注意我这个地方引入的是springbooot2.0.1 版本，首先这么做下去，再升级

<?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.</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0..RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.cxy</groupId>
    <artifactId>elasticsearch</artifactId>
    <version>0.0.-SNAPSHOT</version>
    <name>elasticsearch</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>org.elasticsearch.client</groupId>
            <artifactId>elasticsearch-rest-high-level-client</artifactId>
            <version>6.2.</version>
        </dependency>
        <dependency>
            <groupId>org.elasticsearch</groupId>
            <artifactId>elasticsearch</artifactId>
            <version>6.2.</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-io</artifactId>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>
 
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
 
</project>

yml文件：

server:
  port: ${port:}
spring:
  application:
    name:search-service
  elasticsearch:
    hostlist: ${eshostlist:127.0.0.1:}

es的配置类：

package com.cxy.elasticsearch.config;
 
import org.apache.http.HttpHost;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
 
@Configuration
public class ElasticsearchConfig {
 
    @Value("${spring.elasticsearch.hostlist}")
    private String hostlist;
 
    @Bean
    public RestHighLevelClient restHighLevelClient(){
        //解析hostlist配置信息
        String[] split = hostlist.split(",");
        //创建HttpHost数组，其中存放es主机和端口的配置信息
        HttpHost[] httpHostArray = new HttpHost[split.length];
        for(int i=;i<split.length;i++){
            String item = split[i];
            httpHostArray[i] = new HttpHost(item.split(":")[], Integer.parseInt(item.split(":")[]), "http");
        }
        //创建RestHighLevelClient客户端
        return new RestHighLevelClient(RestClient.builder(httpHostArray));
    }
 
    //项目主要使用RestHighLevelClient，对于低级的客户端暂时不用
    @Bean
    public RestClient restClient(){
        //解析hostlist配置信息
        String[] split = hostlist.split(",");
        //创建HttpHost数组，其中存放es主机和端口的配置信息
        HttpHost[] httpHostArray = new HttpHost[split.length];
        for(int i=;i<split.length;i++){
            String item = split[i];
            httpHostArray[i] = new HttpHost(item.split(":")[], Integer.parseInt(item.split(":")[]), "http");
        }
        return RestClient.builder(httpHostArray).build();
    }
 
}

然后再看我的controller

package com.cxy.elasticsearch.controller;
 
import org.elasticsearch.action.DocWriteResponse;
import org.elasticsearch.action.admin.indices.create.CreateIndexRequest;
import org.elasticsearch.action.admin.indices.create.CreateIndexResponse;
import org.elasticsearch.action.admin.indices.delete.DeleteIndexRequest;
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.client.IndicesClient;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.common.xcontent.XContentType;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;
 
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;
 
@RestController
public class EsController {
    @Autowired
    RestHighLevelClient client;
 
    @Autowired
    RestClient restClient;
    @RequestMapping(value = "/createIndex" ,method = RequestMethod.POST)
    public String createIndex(){
        //创建索引请求对象
        CreateIndexRequest createIndexRequest = new CreateIndexRequest("chenxuyou3");
        // 设置参数
        createIndexRequest.settings(Settings.builder().put("number_of_shards","").put("number_of_replicas",""));
        //指定映射
        createIndexRequest.mapping("doc"," {\n" +
                " \t\"properties\": {\n" +
                "            \"studymodel\":{\n" +
                "             \"type\":\"keyword\"\n" +
                "           },\n" +
                "            \"name\":{\n" +
                "             \"type\":\"keyword\"\n" +
                "           },\n" +
                "           \"description\": {\n" +
                "              \"type\": \"text\",\n" +
                "              \"analyzer\":\"ik_max_word\",\n" +
                "              \"search_analyzer\":\"ik_smart\"\n" +
                "           },\n" +
                "           \"pic\":{\n" +
                "             \"type\":\"text\",\n" +
                "             \"index\":false\n" +
                "           }\n" +
                " \t}\n" +
                "}", XContentType.JSON);
        //指定索引操作的客户端
        IndicesClient indices = client.indices();
        //执行创建索引库
        CreateIndexResponse createIndexResponse = null;
        try {
            createIndexResponse = indices.create(createIndexRequest);
        } catch (IOException e) {
            e.printStackTrace();
        }
        boolean acknowledged = createIndexResponse.isAcknowledged();
        //获取返回结果
        System.err.println(acknowledged);
        return "ok";
    }
    @RequestMapping(value = "/deleteIndex",method = RequestMethod.POST)
    public String deleteIndex(){
        DeleteIndexRequest chenxuyou3 = new DeleteIndexRequest("chenxuyou2");
        IndicesClient indices = client.indices();
        AcknowledgedResponse delete =null;
        try {
            delete = indices.delete(chenxuyou3);
        } catch (IOException e) {
            e.printStackTrace();
        }
        boolean acknowledged = delete.isAcknowledged();
        System.err.println(acknowledged);
        return "";
    }
    @RequestMapping(value = "/addDoc",method = RequestMethod.POST)
    public String addDoc(){
//文档内容
        //准备json数据
        Map<String, Object> jsonMap = new HashMap<>();
        jsonMap.put("name", "spring cloud实战");
        jsonMap.put("description", "本课程主要从四个章节进行讲解： 1.微服务架构入门 2.spring cloud 基础入门 3.实战Spring Boot 4.注册中心eureka。");
        jsonMap.put("studymodel", "");
        SimpleDateFormat dateFormat =new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        jsonMap.put("timestamp", dateFormat.format(new Date()));
        jsonMap.put("price", 5.6f);
 
        //创建索引创建对象
        //带有type的方法已经废弃
       // IndexRequest indexRequest = new IndexRequest("chenxuyou3","doc");
        IndexRequest indexRequest = new IndexRequest("chenxuyou3");
        //文档内容
        indexRequest.source(jsonMap);
        //通过client进行http的请求
        IndexResponse indexResponse = null;
        try {
            indexResponse = client.index(indexRequest);
        } catch (IOException e) {
            e.printStackTrace();
        }
        DocWriteResponse.Result result = indexResponse.getResult();
        System.err.println(result);
        return "ok";
    }
    @RequestMapping(value = "/selectDoc",method = RequestMethod.GET)
    public String selectDoc(){
        //查询请求对象
       // GetRequest getRequest = new GetRequest("chenxuyou2","doc","8tyV-m4B7rvW_ZY4LvVU");
        GetRequest getRequest = new GetRequest("chenxuyou3","doc","8tyV-m4B7rvW_ZY4LvVU");
        GetResponse getResponse = null;
        try {
            getResponse = client.get(getRequest);
        } catch (IOException e) {
            e.printStackTrace();
        }
        //得到文档的内容
        Map<String, Object> sourceAsMap = getResponse.getSourceAsMap();
        System.out.println(sourceAsMap);
        return "ok" ;
    }
 
}

然后启动项目可以看到很清晰的运行

调用 localhost:8085/createIndex

可以看到成功了，后面的也就自然可以操作了。

三问题一：

修改springboot的版本为2.1.8，环境：我使用的es版本是6.2.1 版本：

出现问题：

{
    "timestamp": "2019-12-15T04:46:53.518+0000",
    "status": ,
    "error": "Internal Server Error",
    "message": "org.elasticsearch.client.Request.<init>(Ljava/lang/String;Ljava/lang/String;)V",
    "path": "/createIndex"
}

控制台：

java.lang.NoSuchMethodError: org.elasticsearch.client.Request.<init>(Ljava/lang/String;Ljava/lang/String;)V
    at org.elasticsearch.client.RestClient.performRequest(RestClient.java:) ~[elasticsearch-rest-client-6.4..jar:6.2.]
    at org.elasticsearch.client.RestHighLevelClient.performRequest(RestHighLevelClient.java:) ~[elasticsearch-rest-high-level-client-6.2..jar:6.2.]
    at org.elasticsearch.client.RestHighLevelClient.performRequestAndParseEntity(RestHighLevelClient.java:) ~[elasticsearch-rest-high-level-client-6.2..jar:6.2.]
    at org.elasticsearch.client.IndicesClient.create(IndicesClient.java:) ~[elasticsearch-rest-high-level-client-6.2..jar:6.2.]
    at com.cxy.elasticsearch.controller.EsController.createIndex(EsController.java:) ~[classes/:na]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_191]
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:) ~[na:1.8.0_191]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:) ~[na:1.8.0_191]
    at java.lang.reflect.Method.invoke(Method.java:) ~[na:1.8.0_191]
    at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:) ~[spring-web-5.1..RELEASE.jar:5.1..RELEASE]
    at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:) ~[spring-web-5.1..RELEASE.jar:5.1..RELEASE]
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:) ~[spring-webmvc-5.1..RELEASE.jar:5.1..RELEASE]
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:) ~[spring-webmvc-5.1..RELEASE.jar:5.1..RELEASE]
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:) ~[spring-webmvc-5.1..RELEASE.jar:5.1..RELEASE]
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:) ~[spring-webmvc-5.1..RELEASE.jar:5.1..RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:) ~[spring-webmvc-5.1..RELEASE.jar:5.1..RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:) ~[spring-webmvc-5.1..RELEASE.jar:5.1..RELEASE]
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:) ~[spring-webmvc-5.1..RELEASE.jar:5.1..RELEASE]
    at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:) ~[spring-webmvc-5.1..RELEASE.jar:5.1..RELEASE]
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:) ~[tomcat-embed-core-9.0..jar:9.0.]
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:) ~[spring-webmvc-5.1..RELEASE.jar:5.1..RELEASE]
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:) ~[tomcat-embed-core-9.0..jar:9.0.]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:) ~[tomcat-embed-core-9.0..jar:9.0.]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:) ~[tomcat-embed-core-9.0..jar:9.0.]
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:) ~[tomcat-embed-websocket-9.0..jar:9.0.]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:) ~[tomcat-embed-core-9.0..jar:9.0.]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:) ~[tomcat-embed-core-9.0..jar:9.0.]
    at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:) ~[spring-web-5.1..RELEASE.jar:5.1..RELEASE]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:) ~[spring-web-5.1..RELEASE.jar:5.1..RELEASE]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:) ~[tomcat-embed-core-9.0..jar:9.0.]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:) ~[tomcat-embed-core-9.0..jar:9.0.]
    at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:) ~[spring-web-5.1..RELEASE.jar:5.1..RELEASE]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:) ~[spring-web-5.1..RELEASE.jar:5.1..RELEASE]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:) ~[tomcat-embed-core-9.0..jar:9.0.]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:) ~[tomcat-embed-core-9.0..jar:9.0.]
    at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:) ~[spring-web-5.1..RELEASE.jar:5.1..RELEASE]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:) ~[spring-web-5.1..RELEASE.jar:5.1..RELEASE]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:) ~[tomcat-embed-core-9.0..jar:9.0.]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:) ~[tomcat-embed-core-9.0..jar:9.0.]
    at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:) ~[spring-web-5.1..RELEASE.jar:5.1..RELEASE]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:) ~[spring-web-5.1..RELEASE.jar:5.1..RELEASE]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:) ~[tomcat-embed-core-9.0..jar:9.0.]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:) ~[tomcat-embed-core-9.0..jar:9.0.]
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:) ~[tomcat-embed-core-9.0..jar:9.0.]
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:) [tomcat-embed-core-9.0..jar:9.0.]
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:) [tomcat-embed-core-9.0..jar:9.0.]
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:) [tomcat-embed-core-9.0..jar:9.0.]
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:) [tomcat-embed-core-9.0..jar:9.0.]
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:) [tomcat-embed-core-9.0..jar:9.0.]
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:) [tomcat-embed-core-9.0..jar:9.0.]
    at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:) [tomcat-embed-core-9.0..jar:9.0.]
    at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:) [tomcat-embed-core-9.0..jar:9.0.]
    at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:) [tomcat-embed-core-9.0..jar:9.0.]
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:) [tomcat-embed-core-9.0..jar:9.0.]
    at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:) [tomcat-embed-core-9.0..jar:9.0.]
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:) [na:1.8.0_191]
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:) [na:1.8.0_191]
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:) [tomcat-embed-core-9.0..jar:9.0.]
    at java.lang.Thread.run(Thread.java:) [na:1.8.0_191]

java.lang.NoSuchMethodError: org.elasticsearch.client.Request.<init>(Ljava/lang/String;Ljava/lang/String;)V

这句话的具体意思是这样的，就是没有这个方法，Request对象init的时候创建使用（String，String）后面v是值得意思

可以很清楚，就是升级时候，这个方法没了

    /** @deprecated */
    @Deprecated
    public Response performRequest(String method, String endpoint, Map<String, String> params, Header... headers) throws IOException {
        Request request = new Request(method, endpoint);
        addParameters(request, params);
        addHeaders(request, headers);
        return this.performRequest(request);
    }

由于这个方法已经废弃了，所以在重新去找的时候，版本升级，springboot就没有去找这个类，

所以就报错了

四问题二

出现了上叙问题之后，我想到了解决方法，就是将client得版本升级为最新得，7.23

然后还有就是他那个type得移除，构造方法里面不能有type

最终由于跟我es版本不一致，

Search problem, contains unrecognized parameter: [typed_keys]

报包含错误得字段，我在删除得时候明没什么都没有

然后将版本进行升级：升级到6.6.1就成功了

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