爬虫案例 - 爬取京东的手机数据

爬虫案例

主要目的是 HttpClient 和 Jsoup 的学习

1.需求分析

首先访问京东，搜索手机，分析页面，我们抓取以下商品数据： 商品图片、价格、标题、商品详情页

1.1.SPU 和 SKU

2.环境准备

2.1.数据库

CREATE TABLE `jd_item` ( 
`id` BIGINT(10) NOT NULL AUTO_INCREMENT COMMENT '主键 id', 
`spu` BIGINT(15) DEFAULT NULL COMMENT '商品集合 id', 
`sku` BIGINT(15) DEFAULT NULL COMMENT '商品最小品类单元 id', 
`title` VARCHAR(100) DEFAULT NULL COMMENT '商品标题', 
`price` BIGINT(10) DEFAULT NULL COMMENT '商品价格', 
`pic` VARCHAR(200) DEFAULT NULL COMMENT '商品图片',
`url` VARCHAR(200) DEFAULT NULL COMMENT '商品详情地址', 
`created` DATETIME DEFAULT NULL COMMENT '创建时间', 
`updated` DATETIME DEFAULT NULL COMMENT '更新时间', 
PRIMARY KEY (`id`), 
KEY `sku` (`sku`) USING BTREE )
 ENGINE=INNODB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8 COMMENT='京东商品表';

2.2.POM.xml

<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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0modelVersion>

    <parent>
        <groupId>org.springframework.bootgroupId>
        <artifactId>spring-boot-starter-parentartifactId>
        <version>2.0.2.RELEASEversion>
    parent>

    <groupId>com.rhoningroupId>
    <artifactId>crawlerTest_jdartifactId>
    <version>1.0-SNAPSHOTversion>

    <dependencies>
        
        <dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-starter-webartifactId>
        dependency>
        
        <dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-starter-data-jpaartifactId>
        dependency>
        
        <dependency>
            <groupId>mysqlgroupId>
            <artifactId>mysql-connector-javaartifactId>
        dependency>
        
        <dependency>
            <groupId>org.apache.httpcomponentsgroupId>
            <artifactId>httpclientartifactId>
        dependency>
        
        <dependency>
            <groupId>org.jsoupgroupId>
            <artifactId>jsoupartifactId>
            <version>1.10.3version>
        dependency>
        
        <dependency>
            <groupId>org.apache.commonsgroupId>
            <artifactId>commons-lang3artifactId>
        dependency>
    dependencies>

project>

2.3.添加配置文件

#DB Configuration:
spring.datasource.driverClassName=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://127.0.0.1:3306/test
spring.datasource.username=root
spring.datasource.password=root

#JPA Configuration: 
spring.jpa.database=MySQL
spring.jpa.show-sql=true

3.代码实现

3.1.pojo

package com.rhonin.jd.pojo;

import javax.persistence.*;
import java.util.Date;

@Entity
@Table(name = "jd_item")
public class Item {
    //主键
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY) 
    //标准产品单位（商品集合）
    private Long spu;
    // 库存量单位（最小品类单元）
    private Long sku;
    // 商品标题
    private String title;
    // 商品价格
    private Double price;
    // 商品图片
    private String pic;
    // 商品详情地址
    private String url;
    // 创建时间
    private Date created;
    // 更新时间
    private Date updated;
 	//get set方法略
}

3.2.Dao

public interface ItemDao extends JpaRepository<Item,Long> {
}

3.3.Service&Impl

public interface ItemService {
    /**
     * 保存商品
     * @param item
     */
    public void save(Item item);

    /**
     * 根据条件查询商品
     * @param item
     * @return
     */
    public List<Item> findAll(Item item);
}

---

public class ItemServiceImpl implements ItemService {
    @Autowired
    private ItemDao itemDao;

    @Override
    public void save(Item item) {
        this.itemDao.save(item);
    }

    @Override
    public List<Item> findAll(Item item) {
        //声明查询条件
        Example<Item> example = Example.of(item);
        //根据查询条件进行查询数据
        List<Item> list = this.itemDao.findAll(example);
        return list;
    }
}

3.4.引导类

@SpringBootApplication
@EnableScheduling
public class application {
    public static void main(String[] args) {
        SpringApplication.run(application.class, args);
    }
}

3.5.封装HttpClient

@Component
public class HttpUtils {

    private PoolingHttpClientConnectionManager cm;

    public HttpUtils() {
        this.cm = new PoolingHttpClientConnectionManager();

        //设置最大连接数
        this.cm.setMaxTotal(100);

        //设置每个主机的最大连接数
        this.cm.setDefaultMaxPerRoute(10);
    }

    /**
     * 根据请求地址下载页面数据
     *
     * @param url
     * @return 页面数据
     */
    public String doGetHtml(String url) {
        //获取HttpClient对象
        CloseableHttpClient httpClient = HttpClients.custom().setConnectionManager(this.cm).build();

        //创建httpGet请求对象，设置url地址
        HttpGet httpGet = new HttpGet(url);

        //设置请求信息
        httpGet.setConfig(this.getConfig());

        CloseableHttpResponse response = null;


        try {
            //使用HttpClient发起请求，获取响应
            response = httpClient.execute(httpGet);

            //解析响应，返回结果
            if (response.getStatusLine().getStatusCode() == 200) {
                //判断响应体Entity是否不为空，如果不为空就可以使用EntityUtils
                if (response.getEntity() != null) {
                    String content = EntityUtils.toString(response.getEntity(), "utf8");
                    return content;
                }
            }

        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            //关闭response
            if (response != null) {
                try {
                    response.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        //返回空串
        return "";
    }


    /**
     * 下载图片
     *
     * @param url
     * @return 图片名称
     */
    public String doGetImage(String url) {
        //获取HttpClient对象
        CloseableHttpClient httpClient = HttpClients.custom().setConnectionManager(this.cm).build();

        //创建httpGet请求对象，设置url地址
        HttpGet httpGet = new HttpGet(url);

        //设置请求信息
        httpGet.setConfig(this.getConfig());

        CloseableHttpResponse response = null;


        try {
            //使用HttpClient发起请求，获取响应
            response = httpClient.execute(httpGet);

            //解析响应，返回结果
            if (response.getStatusLine().getStatusCode() == 200) {
                //判断响应体Entity是否不为空
                if (response.getEntity() != null) {
                    //下载图片
                    //获取图片的后缀
                    String extName = url.substring(url.lastIndexOf("."));

                    //创建图片名，重命名图片
                    String picName = UUID.randomUUID().toString() + extName;

                    //下载图片
                    //声明OutPutStream
                    OutputStream outputStream = new FileOutputStream(new File("C:\\Users\\tree\\Desktop\\images\\" +
                            picName));
                    response.getEntity().writeTo(outputStream);

                    //返回图片名称
                    return picName;
                }
            }

        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            //关闭response
            if (response != null) {
                try {
                    response.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        //如果下载失败，返回空串
        return "";
    }

    //设置请求信息
    private RequestConfig getConfig() {
        RequestConfig config = RequestConfig.custom()
                .setConnectTimeout(1000)    //创建连接的最长时间
                .setConnectionRequestTimeout(500)  // 获取连接的最长时间
                .setSocketTimeout(10000)    //数据传输的最长时间
                .build();

        return config;
    }
}

3.6.实现数据抓取

@Component
public class ItemTask {

    @Autowired
    private HttpUtils httpUtils;
    @Autowired
    private ItemService itemService;

    private static final ObjectMapper MAPPER =  new ObjectMapper();


    //当下载任务完成后，间隔多长时间进行下一次的任务。
    @Scheduled(fixedDelay = 100 * 1000)
    public void itemTask() throws Exception {
        //声明需要解析的初始地址
        String url = "https://search.jd.com/Search?keyword=%E6%89%8B%E6%9C%BA&enc=utf-8&qrst=1&rt=1&stop=1&vt=2&wq" +
                "=%E6%89%8B%E6%9C%BA&cid2=653&cid3=655&s=113&click=0&page=";

        //按照页面对手机的搜索结果进行遍历解析
        for (int i = 1; i < 10; i = i + 2) {
            String html = httpUtils.doGetHtml(url + i);

            //解析页面，获取商品数据并存储
            this.parse(html);
        }


        System.out.println("手机数据抓取完成！");


    }

    //解析页面，获取商品数据并存储
    private void parse(String html) throws Exception {
        //解析html获取Document
        Document doc = Jsoup.parse(html);

        //获取spu信息
        Elements spuEles = doc.select("div#J_goodsList > ul > li");

        for (Element spuEle : spuEles) {
            //获取spu
            long spu = Long.parseLong(spuEle.attr("data-spu"));

            //获取sku信息
            Elements skuEles = spuEle.select("li.ps-item");

            for (Element skuEle : skuEles) {
                //获取sku
                long sku = Long.parseLong(skuEle.select("[data-sku]").attr("data-sku"));

                //根据sku查询商品数据
                Item item = new Item();
                item.setSku(sku);
                List<Item> list = this.itemService.findAll(item);

                if(list.size()>0) {
                    //如果商品存在，就进行下一个循环，该商品不保存，因为已存在
                    continue;
                }

                //设置商品的spu
                item.setSpu(spu);

                //获取商品的详情的url
                String itemUrl = "https://item.jd.com/" + sku + ".html";
                item.setUrl(itemUrl);


                //获取商品的图片
                String picUrl ="https:"+ skuEle.select("img[data-sku]").first().attr("data-lazy-img");
                picUrl = picUrl.replace("/n9/","/n1/");
                String picName = this.httpUtils.doGetImage(picUrl);
                item.setPic(picName);

                //获取商品的价格
                String priceJson = this.httpUtils.doGetHtml("https://p.3.cn/prices/mgets?skuIds=J_" + sku);
                double price = MAPPER.readTree(priceJson).get(0).get("p").asDouble();
                item.setPrice(price);


                //获取商品的标题
                String itemInfo = this.httpUtils.doGetHtml(item.getUrl());
                String title = Jsoup.parse(itemInfo).select("div.sku-name").text();
                item.setTitle(title);


                item.setCreated(new Date());
                item.setUpdated(item.getCreated());

                //保存商品数据到数据库中
                this.itemService.save(item);

            }
        }
    }

}