ElasticSearch

一、安装

1、安装ElasticSearch

1.1window下安装

1.1.1解压缩即可使用

1.1.2目录结构:

1.2安装ElasticSearch-head界面显示

1.2.1下载地址:

https://github.com/mobz/elasticsearch-head

1.2.2安装步骤(需要node.js环境):

  • cd elasticsearch-head
  • npm install
  • npm run start

1.2.3解决跨域问题

修改elasticsearch.yml,加上

http.cors.enabled: true
http.cors.allow-origin: "*"

1.3安装kibana

1.3.1什么是kibana?

Kibana是一个基于Node.js的Elasticsearch索引库数据统计工具,可以利用Elasticsearch的聚合功能,生成各种图表,如柱形图,线状图,饼图等。

而且还提供了操作Elasticsearch索引数据的控制台,并且提供了一定的API提示,非常有利于我们学习Elasticsearch的语法。

1.3.2安装步骤

因为Kibana依赖于node,我们的虚拟机没有安装node,而window中安装过。所以我们选择在window下使用kibana。

kibana版本需与elasticsearch保持一致

1)解压即可使用

2)汉化界面:修改kibana.yml

加上

i18n.locale: "zh-CN"

1.4安装ik分词器

1.4.1解压到/path/to/elasticsearch-7.6.1/plugins

1.4.2使用

GET /_analyze
{
  "analyzer": "ik_smart",
  "text": "白云城主叶孤城"
}

GET /_analyze
{
  "analyzer": "ik_max_word",
  "text": "白云城主叶孤城"
}

效果:

 不足:叶孤城没有成为一个词

1.4.3添加自定义分词字典

1)新建my.dic

2)配置IKAnalyzer.cfg.xml:

3)效果:

二、操作Elasticsearch

2.1基本概念

Elasticsearch也是基于Lucene的全文检索库,本质也是存储数据,很多概念与MySQL类似的。

对比关系:

索引(indices)--------------------------------Databases 数据库
​
类型(type)-----------------------------------Table 数据表
​
文档(Document)-------------------------------Row 行
​
字段(Field)----------------------------------Columns 列 

详细说明:

是不是与Lucene和solr中的概念类似。

另外,在SolrCloud中,有一些集群相关的概念,在Elasticsearch也有类似的:

  • 索引集(Indices,index的复数):逻辑上的完整索引 collection1

  • 分片(shard):数据拆分后的各个部分

  • 副本(replica):每个分片的复制

要注意的是:Elasticsearch本身就是分布式的,因此即便你只有一个节点,Elasticsearch默认也会对你的数据进行分片和副本操作,当你向集群添加新数据时,数据也会在新加入的节点中进行平衡。



2.2springboot集成elasticsearch

官方文档地址:https://www.elastic.co/guide/en/elasticsearch/client/java-rest/7.6/java-rest-high.html

2.2.1创建springboot工程

 

 

添加配置类:

package com.example.esapi.config;


import org.apache.http.HttpHost;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class ElasticSearchConfig {

    @Bean
    public RestHighLevelClient restHighLevelClient(){
        RestHighLevelClient restHighLevelClient = new RestHighLevelClient(
                RestClient.builder(
                        new HttpHost("127.0.0.1", 9200, "http")
                )

        );
        return restHighLevelClient;

    }

}

注意:解决版本不对称问题

2.2.2索引操作

package com.example.esapi;

import org.elasticsearch.action.admin.indices.delete.DeleteIndexRequest;
import org.elasticsearch.action.support.master.AcknowledgedResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.client.indices.CreateIndexRequest;
import org.elasticsearch.client.indices.CreateIndexResponse;
import org.elasticsearch.client.indices.GetIndexRequest;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;

import java.io.IOException;

@SpringBootTest
class EsApiApplicationTests {

    @Autowired
    private RestHighLevelClient restHighLevelClient;

    //测试索引的创建
    @Test
    void testCreateIndex() throws IOException {
        //1.创建索引请求
        CreateIndexRequest request = new CreateIndexRequest("my_index");
        //2.客户端执行请求IndiceClient,请求后获得响应
        CreateIndexResponse createIndexResponse =
                restHighLevelClient.indices().create(request, RequestOptions.DEFAULT);
        System.out.println(createIndexResponse);
    }

    //测试获取索引
    @Test
    void testExistIndex() throws IOException {
        GetIndexRequest request = new GetIndexRequest("my_index");
        boolean exists = restHighLevelClient.indices().exists(request, RequestOptions.DEFAULT);
        System.out.println(exists);
    }

    //测试删除索引
    @Test
    void testDeleteIndex() throws IOException {
        DeleteIndexRequest request = new DeleteIndexRequest("my_index");
        //删除
        AcknowledgedResponse delete = restHighLevelClient.indices().delete(request, RequestOptions.DEFAULT);
        System.out.println(delete.isAcknowledged());
    }


}

2.2.3文档操作

//测试添加文档
    @Test
    void testAddDocument() throws IOException {
        //创建对象
        User user = new User("jack", 22);
        //创建请求
        IndexRequest request = new IndexRequest("my_index");
        //规则 put/my_index/_doc/1
        request.id("1");
        request.timeout("1s");
        //将我们的数据放入请求 json
        request.source(JSON.toJSONString(user), XContentType.JSON);
        //客户端发送请求,获取响应结果
        IndexResponse indexResponse = restHighLevelClient.index(request, RequestOptions.DEFAULT);

        System.out.println(indexResponse.toString());
        System.out.println(indexResponse.status());
    }

    //获取文档,判断是否存在 get/index/doc/1
    @Test
    void testIsExists() throws IOException {
        GetRequest request = new GetRequest("my_index", "1");
        //不获取返回的_source的上下文
        request.fetchSourceContext(new FetchSourceContext(false));
        request.storedFields("_none_");

        boolean exists = restHighLevelClient.exists(request, RequestOptions.DEFAULT);
        System.out.println(exists);
    }

    //获得文档的信息
    @Test
    void testGetDocument() throws IOException {
        GetRequest request = new GetRequest("my_index", "1");
        GetResponse getResponse = restHighLevelClient.get(request, RequestOptions.DEFAULT);
        System.out.println(getResponse.getSourceAsString()); //打印文档的内容
        System.out.println(getResponse);
    }

    //更新文档的信息
    @Test
    void testUpdateDocument() throws IOException {
        //创建对象
        User user = new User("mike", 12);
        //创建请求
        UpdateRequest request = new UpdateRequest("my_index", "1");
        request.timeout("1s");

        //将我们的数据放入请求 json
        request.doc(JSON.toJSONString(user), XContentType.JSON);
        //客户端发送请求,获取响应结果
        UpdateResponse updateResponse = restHighLevelClient.update(request, RequestOptions.DEFAULT);

        System.out.println(updateResponse.status());
    }


    //删除文档记录
    @Test
    void testDeleteDocument() throws IOException {
        DeleteRequest deleteRequest = new DeleteRequest("my_index", "1");
        deleteRequest.timeout("1s");

        DeleteResponse deleteResponse = restHighLevelClient.delete(deleteRequest, RequestOptions.DEFAULT);
        System.out.println(deleteResponse.status());
    }

    //批量操作 插入数据
    @Test
    void testBulkDocument() throws IOException {
        BulkRequest bulkRequest = new BulkRequest();
        bulkRequest.timeout("10s");

        ArrayList<User> users = new ArrayList<>();
        users.add(new User("jack", 11));
        users.add(new User("july", 22));
        users.add(new User("john", 15));
        users.add(new User("dick", 32));
        users.add(new User("lily", 19));
        users.add(new User("lucy", 20));

        //批量处理请求
        for (int i = 0; i < users.size(); i++) {
            bulkRequest.add(
                    new IndexRequest("my_index")
                    .id(""+(i+1))
                    .source(JSON.toJSONString(users.get(i)), XContentType.JSON)
            );
        }
        BulkResponse bulkItemResponses = restHighLevelClient.bulk(bulkRequest, RequestOptions.DEFAULT);
        System.out.println(bulkItemResponses.hasFailures());  //返回false即为成功
    }


    //查询
    @Test
    void testSearch() throws IOException {
        SearchRequest searchRequest = new SearchRequest("my_index");
        //构建搜索条件
        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
        //查询条件,我们可以使用QueryBuilders工具来实现
        TermQueryBuilder termQueryBuilder = QueryBuilders.termQuery("name", "lucy");
        sourceBuilder.query(termQueryBuilder);
        sourceBuilder.timeout(new TimeValue(60, TimeUnit.SECONDS));

        searchRequest.source(sourceBuilder);

        SearchResponse searchResponse = restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT);
        System.out.println(JSON.toJSONString(searchResponse.getHits()));
        System.out.println("----------------------------");
        for (SearchHit documentFields : searchResponse.getHits().getHits()) {
            System.out.println(documentFields.getSourceAsMap());
        }
    }

三、实战

3.1创建项目

1)添加依赖

         <!--        解析网页-->
        <dependency>
            <groupId>org.jsoup</groupId>
            <artifactId>jsoup</artifactId>
            <version>1.10.2</version>
        </dependency>   


        <!-- 阿里fastjson包JSON转换-->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.47</version>
        </dependency>

2)项目结构

3.2源码

1)Content.java

package com.example.jdsearch.pojo;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

@Data
@NoArgsConstructor
@AllArgsConstructor
public class Content {
    private String img;
    private String price;
    private String title;

}

2)ContentService

package com.example.jdsearch.service;


import com.alibaba.fastjson.JSON;
import com.example.jdsearch.pojo.Content;
import com.example.jdsearch.utils.HtmlParseUtil;
import org.elasticsearch.action.bulk.BulkRequest;
import org.elasticsearch.action.bulk.BulkResponse;
import org.elasticsearch.action.index.IndexRequest;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.common.text.Text;
import org.elasticsearch.common.unit.TimeValue;
import org.elasticsearch.common.xcontent.XContentType;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.query.TermQueryBuilder;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightField;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.concurrent.TimeUnit;

@Service
public class ContentService {
    @Autowired
    private RestHighLevelClient restHighLevelClient;


    //解析数据并将数据放入es
    public Boolean parse(String keywords) throws IOException {
        List<Content> contents = new HtmlParseUtil().parse(keywords);

        //把查询到的数据放入es
        BulkRequest bulkRequest = new BulkRequest();
        bulkRequest.timeout("3m");


        //批量处理请求
        for (int i = 0; i < contents.size(); i++) {
            bulkRequest.add(
                    new IndexRequest("jd_index")
                            .source(JSON.toJSONString(contents.get(i)), XContentType.JSON)
            );
        }
        BulkResponse bulkItemResponses = restHighLevelClient.bulk(bulkRequest, RequestOptions.DEFAULT);
        return !bulkItemResponses.hasFailures();  //返回false即为成功

    }


    //搜索
    public List<Map<String, Object>> search(String keywords, Integer pageNo, Integer pageSize) throws IOException {
        if(pageNo <= 1)
            pageNo = 1;

        //条件搜索
        SearchRequest searchRequest = new SearchRequest("jd_index");
        //构建搜索条件
        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();

        //分页
        sourceBuilder.from(pageNo);
        sourceBuilder.size(pageSize);

        //查询条件,我们可以使用QueryBuilders工具来实现
        TermQueryBuilder termQueryBuilder = QueryBuilders.termQuery("title", keywords);
        sourceBuilder.query(termQueryBuilder);
        sourceBuilder.timeout(new TimeValue(60, TimeUnit.SECONDS));


        //高亮
        HighlightBuilder highlightBuilder = new HighlightBuilder();
        highlightBuilder.field("title");
        highlightBuilder.requireFieldMatch(false);//是否需要多个高亮显示
        highlightBuilder.preTags("<span style='color:red'>");
        highlightBuilder.postTags("</span>");
        sourceBuilder.highlighter(highlightBuilder);

        //执行结果
        searchRequest.source(sourceBuilder);
        SearchResponse searchResponse = restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT);

        //解析结果
        ArrayList<Map<String, Object>> list = new ArrayList<>();
        for (SearchHit documentFields : searchResponse.getHits().getHits()) {
            Map<String, HighlightField> highlightFields = documentFields.getHighlightFields();
            HighlightField title = highlightFields.get("title");
            Map<String, Object> sourceAsMap =  documentFields.getSourceAsMap();

            //解析高亮的字段,将原来的字段换成我们高亮的字段即可
            if(title != null){
                Text[] fragments = title.fragments();
                String n_title = "";
                for (Text text : fragments) {
                    n_title += text;
                }
                sourceAsMap.put("title", n_title);
            }


            list.add(sourceAsMap);
        }

        return list;
    }



}

3)HtmlParseUtil

package com.example.jdsearch.utils;

import com.example.jdsearch.pojo.Content;
import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
import org.jsoup.nodes.Element;
import org.jsoup.select.Elements;

import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;

public class HtmlParseUtil {
    public static void main(String[] args) throws IOException {
        HtmlParseUtil htmlParseUtil = new HtmlParseUtil();
       List<Content> contents = htmlParseUtil.parse("java");
       contents.forEach(System.out::println);

    }


    public List<Content> parse(String keywords) throws IOException {
        //准备url
        String url = "https://search.jd.com/Search?keyword="+keywords;
        //解析网页,jsoup返回的document对象就是js中的document对象
        Document document = Jsoup.parse(new URL(url), 30000);
        Element j_goodsList = document.getElementById("J_goodsList");

        List<Content> contents = new ArrayList<>();

        //获取所有的li元素
        Elements elements = j_goodsList.getElementsByTag("li");
        for (Element element : elements) {
            String img = element.getElementsByTag("img").eq(0).attr("data-lazy-img");  //图片延迟加载,不在src
            String price = element.getElementsByClass("p-price").eq(0).text();
            String title = element.getElementsByClass("p-name").eq(0).text();

            contents.add(new Content(img, price, title));

        }

        return contents;
    }
}

4)ContentController

package com.example.jdsearch.web;

import com.example.jdsearch.service.ContentService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.io.IOException;
import java.util.List;
import java.util.Map;

@RestController
public class ContentController {

    @Autowired
    private ContentService contentService;


    //爬取数据
    @RequestMapping("/parse/{keywords}")
    public Boolean parse(@PathVariable("keywords") String keywords) throws IOException {
        return contentService.parse(keywords);

    }

    //查询数据
    @RequestMapping("/search/{keywords}/{pageNo}/{pageSize}")
    public List<Map<String, Object>> search(
            @PathVariable("keywords") String keywords,
            @PathVariable("pageNo") Integer pageNo,
            @PathVariable("pageSize") Integer pageSize) throws IOException {

        return contentService.search(keywords, pageNo, pageSize);

    }
}

5)IndexController

package com.example.jdsearch.web;


import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;

@Controller
public class IndexController {

    @GetMapping({"/", "/index"})
    public String index(){
        return "index";

    }

}

6)index.html

<!DOCTYPE html>
<html xmlns:th="http://www.thymeleaf.org">

<head>
    <meta charset="utf-8"/>
    <title>狂神说Java-ES仿京东实战</title>
    <link rel="stylesheet" th:href="@{/css/style.css}"/>

</head>

<body class="pg">
<div class="page" id="app">
    <div id="mallPage" class=" mallist tmall- page-not-market ">

        <!-- 头部搜索 -->
        <div id="header" class=" header-list-app">
            <div class="headerLayout">
                <div class="headerCon ">
                    <!-- Logo-->
                    <h1 id="mallLogo">
                        <img th:src="@{/images/jdlogo.png}" alt="">
                    </h1>

                    <div class="header-extra">

                        <!--搜索-->
                        <div id="mallSearch" class="mall-search">
                            <form name="searchTop" class="mallSearch-form clearfix">
                                <fieldset>
                                    <legend>天猫搜索</legend>
                                    <div class="mallSearch-input clearfix">
                                        <div class="s-combobox" id="s-combobox-685">
                                            <div class="s-combobox-input-wrap">
                                                <input type="text" autocomplete="off" value="dd" id="mq"
                                                       class="s-combobox-input" aria-haspopup="true" v-model="keywords">
                                            </div>
                                        </div>
                                        <button type="submit" id="searchbtn" @click.prevent="search">搜索</button>
                                    </div>
                                </fieldset>
                            </form>
                            <ul class="relKeyTop">
                                <li><a>狂神说Java</a></li>
                                <li><a>狂神说前端</a></li>
                                <li><a>狂神说Linux</a></li>
                                <li><a>狂神说大数据</a></li>
                                <li><a>狂神聊理财</a></li>
                            </ul>
                        </div>
                    </div>
                </div>
            </div>
        </div>

        <!-- 商品详情页面 -->
        <div id="content">
            <div class="main">
                <!-- 品牌分类 -->
                <form class="navAttrsForm">
                    <div class="attrs j_NavAttrs" style="display:block">
                        <div class="brandAttr j_nav_brand">
                            <div class="j_Brand attr">
                                <div class="attrKey">
                                    品牌
                                </div>
                                <div class="attrValues">
                                    <ul class="av-collapse row-2">
                                        <li><a href="#"> 狂神说 </a></li>
                                        <li><a href="#"> Java </a></li>
                                    </ul>
                                </div>
                            </div>
                        </div>
                    </div>
                </form>

                <!-- 排序规则 -->
                <div class="filter clearfix">
                    <a class="fSort fSort-cur">综合<i class="f-ico-arrow-d"></i></a>
                    <a class="fSort">人气<i class="f-ico-arrow-d"></i></a>
                    <a class="fSort">新品<i class="f-ico-arrow-d"></i></a>
                    <a class="fSort">销量<i class="f-ico-arrow-d"></i></a>
                    <a class="fSort">价格<i class="f-ico-triangle-mt"></i><i class="f-ico-triangle-mb"></i></a>
                </div>

                <!-- 商品详情 -->
                <div class="view grid-nosku">

                    <div class="product" v-for="item in items">
                        <div class="product-iWrap">
                            <!--商品封面-->
                            <div class="productImg-wrap">
                                <a class="productImg">
                                    <img :src="item.img">
                                </a>
                            </div>
                            <!--价格-->
                            <p class="productPrice">
                                <em>{{item.price}}</em>
                            </p>
                            <!--标题-->
                            <p class="productTitle">
                                <a v-html="item.title"> </a>
                            </p>
                            <!-- 店铺名 -->
                            <div class="productShop">
                                <span>店铺: 狂神说Java </span>
                            </div>
                            <!-- 成交信息 -->
                            <p class="productStatus">
                                <span>月成交<em>999笔</em></span>
                                <span>评价 <a>3</a></span>
                            </p>
                        </div>
                    </div>
                </div>
            </div>
        </div>
    </div>
</div>

<script th:src="@{/js/vue.min.js}"></script>
<script th:src="@{/js/axios.min.js}"></script>
<script>

    const app = new Vue({
        el: "#app",
        data:{
            keywords:"",
            items: []
        },
        methods:{
            search: function () {
                axios.get("/search/"+this.keywords+"/1/10").then(result => {
                    this.items = result.data;
                })

            }
        }
    })


</script>

</body>
</html>
View Code

7)application.properties

spring.thymeleaf.cache=false

server.port=9090

3.3实现效果

原文地址:https://www.cnblogs.com/dominik/p/14031238.html