搜索学习--Elasticsearch全文搜索服务器的基本使用

骑猪看日落 2022-06-04 10:05 304阅读 0赞

### 前言 ###

之前我们使用Solr全文搜索服务器来建立我们自己的搜索，本篇文章将介绍跟Solr类似的另一种搜索服务器——Elasticsearch。就个人而言，Elasticsearch比Solr使用更方便，只要使用Http通过Json传输就可以去使用了。对于ElasticSearch服务器的部署，分布式，集群这里就先不介绍了。部署启动后，访问 [http://127.0.0.1:9200/][http_127.0.0.1_9200]，显示如下类似信息，说明服务器已经起来了。

> \{  
> “name” : “8n5uD4P”,  
> “cluster\_name” : “elasticsearch”,  
> “cluster\_uuid” : “D-hKMOfgQQKjizry-i41qw”,  
> “version” : \{  
> “number” : “6.0.0”,  
> “build\_hash” : “8f0685b”,  
> “build\_date” : “2017-11-10T18:41:22.859Z”,  
> “build\_snapshot” : false,  
> “lucene\_version” : “7.0.1”,  
> “minimum\_wire\_compatibility\_version” : “5.6.0”,  
> “minimum\_index\_compatibility\_version” : “5.0.0”  
> \},  
> “tagline” : “You Know, for Search”  
> \}  
> 接下来就是通过客户端去调用了，这里使用Java

### 依赖 ###

<dependency>
        <groupId>com.alibaba</groupId>
         <artifactId>fastjson</artifactId>
         <version>1.2.38</version>
     </dependency>
    
     <dependency>
         <groupId>junit</groupId>
         <artifactId>junit</artifactId>
         <version>4.12</version>
         <scope>test</scope>
     </dependency>
    
     <dependency>
         <groupId>org.elasticsearch.client</groupId>
         <artifactId>elasticsearch-rest-client</artifactId>
         <version>5.6.3</version>
     </dependency>

### Core(要存储的对象) ###

package top.yuyufeng.learn.lucene.elasticsearch.core;
    
    import java.util.Date;
    
    /**
     * @author yuyufeng
     * @date 2017/12/6
     */
    public class BlogCore {
        private String blogId;
        private String blogTitle;
        private String blogContent;
        private Date createTime;
        private String keywords;
    
        public String getBlogId() {
            return blogId;
        }
    
        public void setBlogId(String blogId) {
            this.blogId = blogId;
        }
    
        public String getBlogTitle() {
            return blogTitle;
        }
    
        public void setBlogTitle(String blogTitle) {
            this.blogTitle = blogTitle;
        }
    
        public String getBlogContent() {
            return blogContent;
        }
    
        public void setBlogContent(String blogContent) {
            this.blogContent = blogContent;
        }
    
        public Date getCreateTime() {
            return createTime;
        }
    
        public void setCreateTime(Date createTime) {
            this.createTime = createTime;
        }
    
        public String getKeywords() {
            return keywords;
        }
    
        public void setKeywords(String keywords) {
            this.keywords = keywords;
        }
    
        @Override
        public String toString() {
            return "BlogCore{" +
                    "blogId='" + blogId + '\'' +
                    ", blogTitle='" + blogTitle + '\'' +
                    ", blogContent='" + blogContent + '\'' +
                    ", createTime=" + createTime +
                    ", keywords='" + keywords + '\'' +
                    '}';
        }
    }

### 增删改查 ###

### 搜索 ###

package top.yuyufeng.learn.lucene.elasticsearch;
    
    import com.alibaba.fastjson.JSONObject;
    import org.apache.http.Header;
    import org.apache.http.HttpEntity;
    import org.apache.http.HttpHost;
    import org.apache.http.entity.StringEntity;
    import org.apache.http.message.BasicHeader;
    import org.apache.http.util.EntityUtils;
    import org.elasticsearch.client.Response;
    import org.elasticsearch.client.RestClient;
    import org.junit.After;
    import org.junit.Before;
    import org.junit.Test;
    import top.yuyufeng.learn.lucene.elasticsearch.core.BlogCore;
    
    import java.io.IOException;
    import java.util.Collections;
    import java.util.Date;
    
    /**
     * @author yuyufeng
     * @date 2017/12/11
     */
    public class ClientSearchTest {
    
        private RestClient restClient;
        private Response response;
        private Header header;
    
        @Before
        public void testBefore() {
            restClient = RestClient.builder(
                    new HttpHost("127.0.0.1", 9200, "http")).build();
            header = new BasicHeader("Content-Type", "application/json");
        }
    
    
        /**
         * 轻量搜索1
         */
        @Test
        public void testSearch1() throws IOException {
            response = restClient.performRequest("GET", "/test/blog/_search?pretty", header);
            System.out.println(EntityUtils.toString(response.getEntity()));
        }
    
        /**
         * 轻量搜索2
         */
        @Test
        public void testSearch2() throws IOException {
            response = restClient.performRequest("GET", "/test/blog/_search?q=blogTitle:达摩&pretty", header);
            System.out.println(EntityUtils.toString(response.getEntity()));
        }
    
    
    
        /**
         * 使用查询表达式搜索
         */
        @Test
        public void testSearchWithMatch() throws IOException {
            String json = "{" +
                    "    \"query\" : {" +
                    "        \"match\" : {" +
                    "            \"blogTitle\" : \"达摩阿里巴巴\"" +
                    "        }" +
                    "    }" +
                    "}";
            HttpEntity entity = new StringEntity(json, "utf-8");
            response = restClient.performRequest("GET", "/test/blog/_search?pretty", Collections.emptyMap(),entity, header);
            System.out.println(EntityUtils.toString(response.getEntity()));
        }
    
        /**
         * 使用查询表达式搜索
         */
        @Test
        public void testSearchWithMatchAndFilter() throws IOException {
            String json = "{\n" +
                    "    \"query\" : {\n" +
                    "        \"bool\": {\n" +
                    "            \"must\": {\n" +
                    "                \"match\" : {\n" +
                    "                    \"blogTitle\" : \"达摩\" \n" +
                    "                }\n" +
                    "            },\n" +
                    "            \"filter\": {\n" +
                    "                \"range\" : {\n" +
                    "                    \"blogId\" : { \"gt\" : 1 } \n" +
                    "                }\n" +
                    "            }\n" +
                    "        }\n" +
                    "    }\n" +
                    "}";
            HttpEntity entity = new StringEntity(json, "utf-8");
            response = restClient.performRequest("GET", "/test/blog/_search?pretty", Collections.emptyMap(),entity, header);
            System.out.println(EntityUtils.toString(response.getEntity()));
        }
    
        /**
         * 短语搜索  （单词之间紧挨着）
         * @throws IOException
         */
        @Test
        public void testSearchWithMatchPhrase() throws IOException {
            String json = "{\n" +
                    "    \"query\" : {\n" +
                    "        \"match_phrase\" : {\n" +
                    "            \"blogContent\" : \"阿里巴巴达摩院\"\n" +
                    "        }\n" +
                    "    }\n" +
                    "}";
            HttpEntity entity = new StringEntity(json, "utf-8");
            response = restClient.performRequest("GET", "/test/blog/_search?pretty", Collections.emptyMap(),entity, header);
            System.out.println(EntityUtils.toString(response.getEntity()));
        }
    
    
        /**
         * 高亮
         * @throws IOException
         */
        @Test
        public void testSearchWithighlight() throws IOException {
            String json = "{\n" +
                    "    \"query\" : {\n" +
                    "        \"match\" : {\n" +
                    "            \"blogContent\" : \"阿里巴巴全球研究院\"\n" +
                    "        }\n" +
                    "    },\n" +
                    "    \"highlight\": {\n" +
                    "        \"fields\" : {\n" +
                    "            \"blogContent\" : {}\n" +
                    "        }\n" +
                    "    }\n" +
                    "}";
            HttpEntity entity = new StringEntity(json, "utf-8");
            response = restClient.performRequest("GET", "/test/blog/_search?pretty", Collections.emptyMap(),entity, header);
            System.out.println(EntityUtils.toString(response.getEntity()));
        }
    
    
    
    
    
        @After
        public void testAfter() {
            try {
                restClient.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

### 参考文献 ###

*  [https://www.elastic.co/guide/cn/elasticsearch/guide/current/index.html][https_www.elastic.co_guide_cn_elasticsearch_guide_current_index.html]

[http_127.0.0.1_9200]: http://127.0.0.1:9200/
[https_www.elastic.co_guide_cn_elasticsearch_guide_current_index.html]: https://www.elastic.co/guide/cn/elasticsearch/guide/current/index.html