ElasticSearch RestHighLevelClient 通用操作

项目中使用到ElasticSearch作为搜索引擎。而ES的环境搭建自然是十分简单，且本身就适应于分布式环境，因此这块就不多赘述。而其本身特性和查询语句这篇博文不会介绍，如果有机会会深入介绍。

​ 所以这篇博文主要还是介绍Java客户端中如何使用查询搜索引擎中的数据。而使用的Java客户端是官方新推出的RestHighLevelClient，使用Http连接查询结果。但是网上相关资料较少，只有官网的api介绍。所以本文以一个小demo介绍RestHighLevelClient的使用。

项目依赖:
 

dependencies {

    // https://mvnrepository.com/artifact/org.elasticsearch.client/elasticsearch-rest-high-level-client
compile group: 'org.elasticsearch.client', name: 'elasticsearch-rest-high-level-client', version: '5.6.2'
}

Java Client

// Java客户端生成工厂
public class ESClientFactory {

    private static final String HOST = "127.0.0.1";
    private static final int PORT = 9200;
    private static final String SCHEMA = "http";
    private static final int CONNECT_TIME_OUT = 1000;
    private static final int SOCKET_TIME_OUT = 30000;
    private static final int CONNECTION_REQUEST_TIME_OUT = 500;

    private static final int MAX_CONNECT_NUM = 100;
    private static final int MAX_CONNECT_PER_ROUTE = 100;

    private static HttpHost HTTP_HOST = new HttpHost(HOST,PORT,SCHEMA);
    private static boolean uniqueConnectTimeConfig = false;
    private static boolean uniqueConnectNumConfig = true;
    private static RestClientBuilder builder;
    private static RestClient restClient;
    private static RestHighLevelClient restHighLevelClient;

    static {
        init();
    }

    public static void init(){
        builder = RestClient.builder(HTTP_HOST);
        if(uniqueConnectTimeConfig){
            setConnectTimeOutConfig();
        }
        if(uniqueConnectNumConfig){
            setMutiConnectConfig();
        }
        restClient = builder.build();
        restHighLevelClient = new RestHighLevelClient(restClient);
    }

    // 主要关于异步httpclient的连接延时配置
    public static void setConnectTimeOutConfig(){
        builder.setRequestConfigCallback(new RequestConfigCallback() {

            @Override
            public Builder customizeRequestConfig(Builder requestConfigBuilder) {
                requestConfigBuilder.setConnectTimeout(CONNECT_TIME_OUT);
                requestConfigBuilder.setSocketTimeout(SOCKET_TIME_OUT);
                requestConfigBuilder.setConnectionRequestTimeout(CONNECTION_REQUEST_TIME_OUT);
                return requestConfigBuilder;
            }
        });
    }
    // 主要关于异步httpclient的连接数配置
    public static void setMutiConnectConfig(){
        builder.setHttpClientConfigCallback(new HttpClientConfigCallback() {

            @Override
            public HttpAsyncClientBuilder customizeHttpClient(HttpAsyncClientBuilder httpClientBuilder) {
                httpClientBuilder.setMaxConnTotal(MAX_CONNECT_NUM);
                httpClientBuilder.setMaxConnPerRoute(MAX_CONNECT_PER_ROUTE);
                return httpClientBuilder;
            }
        });
    }

    public static RestClient getClient(){
        return restClient;
    }

    public static RestHighLevelClient getHighLevelClient(){
        return restHighLevelClient;
    }

    public static void close() {
        if (restClient != null) {
            try {
                restClient.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }


}

Spring整合以及深入配置

// SpringContext.xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
    xmlns:tx="http://www.springframework.org/schema/tx"
    xmlns:aop="http://www.springframework.org/schema/aop"
    xmlns:p="http://www.springframework.org/schema/p"
    xsi:schemaLocation="
        http://www.springframework.org/schema/beans     
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context.xsd
        http://www.springframework.org/schema/aop
        http://www.springframework.org/schema/aop/spring-aop.xsd
        http://www.springframework.org/schema/tx
        http://www.springframework.org/schema/tx/spring-tx.xsd">

     <context:property-placeholder file-encoding="UTF-8" 
        location="classpath:elasticSearch.properties" ignore-unresolvable="true"/>

    <import resource="spring-esclient.xml"/>

    <bean class="com.xx.product.tools.SpringBeanFactory"/>

    <aop:aspectj-autoproxy expose-proxy="true"/>
    <bean class="com.xx.product.aspect.ElasticSearchAspect"/>

</beans>

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.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Scope;

import com.xx.es.elasticSearch.ESClientSpringFactory;
//使用javaConfig方式配置
@Configuration
@ComponentScan(basePackageClasses=ESClientSpringFactory.class)
public class ESConfig {

    @Value("${httpHost.host}")
    private String host;

    @Value("${httpHost.port}")
    private int port;

    @Value("${httpHost.schema}")
    private String schema;

    @Value("${esclient.connectNum}")
    private Integer connectNum;

    @Value("${esclient.connectPerRoute}")
    private Integer connectPerRoute;



    @Bean
    public HttpHost httpHost(){
        return new HttpHost(host,port,schema);
    }

    @Bean(initMethod="init",destroyMethod="close")
    public ESClientSpringFactory getFactory(){
        return ESClientSpringFactory.
                build(httpHost(), connectNum, connectPerRoute);
    }

    @Bean
    @Scope("singleton")
    public RestClient getRestClient(){
        return getFactory().getClient();
    }

    @Bean
    @Scope("singleton")
    public RestHighLevelClient getRHLClient(){
        return getFactory().getRhlClient();
    }
}

两种配置方法从本质上都是对client进行配置，且达到相同目的。

​ 由于Client配置为单例模式，在Spring中的生命周期随着容器开始结束而开始结束。在定义bean创建和销毁方法后会自动关闭连接。

​ 但是使用一般Java配置时，需要手动关闭。如果在web项目中，可以使用监听器，随着项目的生命周期手动调用开启关闭。

客户端演示

接下来就是最简单的几个demo，校验这种客户端的有效性，同时也为大家试验如何使用这种Java客户端：

数据准备

首先准备要操作的数据：创建一个index为demo，type为demo的新闻索引。
 

//PUT 
http://{{host}}:{{port}}/demo
{
    "mappings":{
        "demo":{
            "properties":{
                "title":{
                    "type":"text"
                },
                "tag":{
                    "type":"keyword"
                },
                "publishTime":{
                    "type":"date"
                }
            }
        }
    }
}

插入数据

API格式

/POST http://{{host}}:{{port}}/demo/demo/
{
    "title":"中国产小型无人机的“对手”来了，俄微型拦截导弹便宜量又多",
    "tag":"军事",
    "publishTime":"2018-01-24T23:59:30Z"
}

Java Client

public class News {

    private String title;
    private String tag;
    private String publishTime;


    public News() {
        super();
    }
    public News(String title, String tag, String publishTime) {
        super();
        this.title = title;
        this.tag = tag;
        this.publishTime = publishTime;
    }
    public String getTitle() {
        return title;
    }
    public void setTitle(String title) {
        this.title = title;
    }
    public String getTag() {
        return tag;
    }
    public void setTag(String tag) {
        this.tag = tag;
    }
    public String getPublishTime() {
        return publishTime;
    }
    public void setPublishTime(String publishTime) {
        this.publishTime = publishTime;
    }
}

@RunWith(SpringJUnit4ClassRunner.class)

@ContextConfiguration("classpath:spring/spring-context.xml")
public class FreeClientTest {

    private String index;

    private String type;

    @Autowired
    private RestHighLevelClient rhlClient;

    @Before
    public void prepare() {
        index = "demo";
        type = "demo";
    }

    @Test
    public void addTest() {
        IndexRequest indexRequest = new IndexRequest(index, type);
        News news = new News();
        news.setTitle("中国产小型无人机的“对手”来了，俄微型拦截导弹便宜量又多");
        news.setTag("军事");
        news.setPublishTime("2018-01-24T23:59:30Z");
        String source = JsonUtil.toString(news);
        indexRequest.source(source, XContentType.JSON);
        try {
            rhlClient.index(indexRequest);
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

}

两种方式均可插入数据。如果有大量数据这样插入未免效率太低，接下来看一看批量插入数据。

批量插入数据

API格式

/POST http://{{host}}:{{port}}/_bulk
{"index":{"_index":"demo","_type":"demo"}}
{"title":"中印边防军于拉达克举行会晤 强调维护边境和平","tag":"军事","publishTime":"2018-01-27T08:34:00Z"}
{"index":{"_index":"demo","_type":"demo"}}
{"title":"费德勒收郑泫退赛礼 进决赛战西里奇","tag":"体育","publishTime":"2018-01-26T14:34:00Z"}
{"index":{"_index":"demo","_type":"demo"}}
{"title":"欧文否认拿动手术威胁骑士 兴奋全明星联手詹皇","tag":"体育","publishTime":"2018-01-26T08:34:00Z"}
{"index":{"_index":"demo","_type":"demo"}}
{"title":"皇马官方通告拉莫斯伊斯科伤情 将缺阵西甲关键战","tag":"体育","publishTime":"2018-01-26T20:34:00Z"}

Java Client

@RunWith(SpringJUnit4ClassRunner.class)

@ContextConfiguration("classpath:spring/spring-context.xml")
public class FreeClientTest {

    private String index;

    private String type;

    @Autowired
    private RestHighLevelClient rhlClient;

    @Before
    public void prepare() {
        index = "demo";
        type = "demo";
    }


    @Test
    public void batchAddTest() {
        BulkRequest bulkRequest = new BulkRequest();
        List<IndexRequest> requests = generateRequests();
        for (IndexRequest indexRequest : requests) {
            bulkRequest.add(indexRequest);
        }
        try {
            rhlClient.bulk(bulkRequest);
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

    public List<IndexRequest> generateRequests(){
        List<IndexRequest> requests = new ArrayList<>();
        requests.add(generateNewsRequest("中印边防军于拉达克举行会晤 强调维护边境和平", "军事", "2018-01-27T08:34:00Z"));
        requests.add(generateNewsRequest("费德勒收郑泫退赛礼 进决赛战西里奇", "体育", "2018-01-26T14:34:00Z"));
        requests.add(generateNewsRequest("欧文否认拿动手术威胁骑士 兴奋全明星联手詹皇", "体育", "2018-01-26T08:34:00Z"));
        requests.add(generateNewsRequest("皇马官方通告拉莫斯伊斯科伤情 将缺阵西甲关键战", "体育", "2018-01-26T20:34:00Z"));
        return requests;
    }

    public IndexRequest generateNewsRequest(String title, String tag, String publishTime){
        IndexRequest indexRequest = new IndexRequest(index, type);
        News news = new News();
        news.setTitle(title);
        news.setTag(tag);
        news.setPublishTime(publishTime);
        String source = JsonUtil.toString(news);
        indexRequest.source(source, XContentType.JSON);
        return indexRequest;
    }

}

 无论通过哪种方式，现在ES中已插入五条文档数据。那么现在就可以通过多种多样的查询方式获得需要的数据了。

查询数据

查询目标：2018年1月26日早八点到晚八点关于费德勒的前十条体育新闻的标题

API 格式

/POST http://{{host}}:{{port}}/demo/demo/_search
{
    "from":"0",
    "size":"10",
    "_source":["title"],
    "query":{
        "bool":{
            "must":{
                "match":{
                    "title":"费德勒"
                }
            },
            "must":{
                "term":{"tag":"体育"}
            },
            "must":{
                "range":{
                    "publishTime":{
                        "gte":"2018-01-26T08:00:00Z",
                        "lte":"2018-01-26T20:00:00Z"
                    }
                }
            }
        }
    }

}

Java Client

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:spring/spring-context.xml")
public class FreeClientTest {

    private String index;

    private String type;

    @Autowired
    private RestHighLevelClient rhlClient;

    @Before
    public void prepare() {
        index = "demo";
        type = "demo";
    }


    @Test
    public void queryTest(){
        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
        sourceBuilder.from(0);
        sourceBuilder.size(10);
        sourceBuilder.fetchSource(new String[]{"title"}, new String[]{});
        MatchQueryBuilder matchQueryBuilder = QueryBuilders.matchQuery("title", "费德勒");
        TermQueryBuilder termQueryBuilder = QueryBuilders.termQuery("tag", "体育");
        RangeQueryBuilder rangeQueryBuilder = QueryBuilders.rangeQuery("publishTime");
        rangeQueryBuilder.gte("2018-01-26T08:00:00Z");
        rangeQueryBuilder.lte("2018-01-26T20:00:00Z");
        BoolQueryBuilder boolBuilder = QueryBuilders.boolQuery();
        boolBuilder.must(matchQueryBuilder);
        boolBuilder.must(termQueryBuilder);
        boolBuilder.must(rangeQueryBuilder);
        sourceBuilder.query(boolBuilder);
        SearchRequest searchRequest = new SearchRequest(index);
        searchRequest.types(type);
        searchRequest.source(sourceBuilder);
        try {
            SearchResponse response = rhlClient.search(searchRequest);
            System.out.println(response);
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

}

查询结果

{
  "took": 1,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "skipped": 0,
    "failed": 0
  },
  "hits": {
    "total": 1,
    "max_score": 2.1507285,
    "hits": [
      {
        "_index": "demo",
        "_type": "demo",
        "_id": "AWE1fnSx00f4t28WJ4D6",
        "_score": 2.1507285,
        "_source": {
          "title": "费德勒收郑泫退赛礼 进决赛战西里奇"
        }
      }
    ]
  }
}

更新文档

如果插入了错误的数据，想要更改或者在文档中新增新的数据，那么就需要更新文档了。

演示 将费德勒的新闻的tag更改为网球类型：

API格式

/POST http://{{host}}:{{port}}/demo/demo/AWE1fnSx00f4t28WJ4D6/_update
{
    "doc":{
        "tag":"网球"
    }
}

Java Client

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:spring/spring-context.xml")
public class FreeClientTest {

    private String index;

    private String type;

    private String id;

    @Autowired
    private RestHighLevelClient rhlClient;

    @Before
    public void prepare() {
        index = "demo";
        type = "demo";
        id = "AWE1fnSx00f4t28WJ4D6";
    }


    @Test
    public void updateTest(){
        UpdateRequest updateRequest = new UpdateRequest(index, type, id);
        Map<String, String> map = new HashMap<>();
        map.put("tag", "网球");
        updateRequest.doc(map);
        try {
            rhlClient.update(updateRequest);
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

}

以上介绍了最简单的doc文档更改，至于脚本更改以后有机会再介绍。

上面文章转自 ElasticSearch RestHighLevelClient 教程（一）通用操作

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