Scrapy框架爬取京东商品

这次抓取京东某类商品的信息，这里我选择了手机品类。

使用scrapy爬虫框架，需要编写和设置的文件主要有phone.py , pipelines.py , items.py , settings.py , 其中主要编写的是前两个文件，最后一个文件主要设置破解反爬方法。

phone.py编写程序如下：

import scrapy
from scrapy.http import Request
from jd_phone.items import JdPhoneItem
import re
import urllib.request

class PhoneSpider(scrapy.Spider):
    name = "phone"
    allowed_domains = ["jd.com"]
    start_urls = ['http://jd.com/']

    #获取商品手机100页网址
    def parse(self, response):
        for i in range(1, 100):
            url = "https://search.jd.com/Search?keyword=手机&enc=utf-8&page="+str(i*2-1)
            yield Request(url=url,callback=self.product_url)

    #获取每页商品链接
    def product_url(self, response):
        urls = response.xpath('//div[@class="p-name p-name-type-2"]/a[@target="_blank"]/@href').extract()
        for i in urls:
            url = response.urljoin(i)
            yield Request(url=url, callback=self.product)

    #获取商品的链接，名称，价格，评论数
    def product(self, response):
        #获取标题
        #title = response.xpath("//li[@class='img-hover']/img/@alt").extract()#部分网页不行
        title = response.xpath("//img/@alt").extract()
        #获取id号，用来构造价格和评论的链接
        pattern = r"(\d+)\.html$"
        id = re.findall(pattern, response.url)
        #得到价格
        priceUrl = "https://p.3.cn/prices/mgets?&skuIds=J_"+str(id[0])
        priceData = urllib.request.urlopen(priceUrl).read().decode("utf-8", "ignore")
        patt = r'"p":"(\d+\.\d+)"'
        price = re.findall(patt, priceData)
        #得到评论数
        commentUrl = "https://club.jd.com/comment/productCommentSummaries.action?referenceIds="+str(id[0])
        commentData = urllib.request.urlopen(commentUrl).read().decode("utf-8", "ignore")
        patt1 = r'"CommentCount":(\d+),'
        comment = re.findall(patt1, commentData)

        item = JdPhoneItem()
        item["url"] = response.url
        item["title"] = title[0]
        item["price"] = price[0]
        item["comment"] = comment[0]
        yield item

pipelines.py编写程序如下：

import pymysql.cursors

class JdPhonePipeline(object):
    #连接登陆mysql，新建数据表
    def __init__(self):
        self.conn=pymysql.connect(host="127.0.0.1",
                                  user="root",
                                  passwd="123456",
                                  charset='utf8mb4',
                                  cursorclass=pymysql.cursors.DictCursor)
        cur = self.conn.cursor()
        cur.execute("CREATE DATABASE jd")
        cur.execute("USE jd")
        cur.execute("CREATE TABLE phone (id INT PRIMARY KEY AUTO_INCREMENT,url VARCHAR(50),title VARCHAR(50),price VARCHAR(10),comment VARCHAR(10))")

    #mysql写入
    def process_item(self, item, spider):
        try:
            url = item["url"]
            title = item["title"]
            price = item["price"]
            comment = item["comment"]
            cur = self.conn.cursor()
            sql = "INSERT INTO phone (url, title, price, comment) VALUES ('"+url+"','"+title+"','"+price+"','"+comment+"')"
            cur.execute(sql)
            self.conn.commit()
            return item
        except Exception as err:
            print(err)

    #关闭连接
    def close_spider(self):
        self.conn.close()

items.py编程如下：

import scrapy


class JdPhoneItem(scrapy.Item):
    # define the fields for your item here like:
    # name = scrapy.Field()
    url = scrapy.Field()
    title = scrapy.Field()
    price = scrapy.Field()
    comment = scrapy.Field()

另外不忘settings.py设置常规破解反爬方法。

这个爬虫项目主要学习了：

1.网页源代码屏蔽数据的获取，使用F12开发人员调试工具获取屏蔽信息的网址，通过下载网址读取数据匹配所需信息。

2.将抓取的数据写入mysql中。

要将mysql数据写进本地csv文件，使用如下方法

mysql> select * from phone

      --> into outfile'c:/ProgramData/MySQL/MySQL Server 5.7/Uploads/phone.csv'

      --> fields terminated by ',' 

      --> optionally enclosed by '"' escaped by '"'

      --> lines terminated by '\n';

解决导出csv中文乱码的问题，将phone.csv复制到桌面，用记事本打开，然后另存为，选择utf8编码。

如果是要将csv数据写进mysql，使用如下方法（先要创建对应数据表）

mysql> load data infile 'c:/ProgramData/MySQL/MySQL Server 5.7/Uploads/phone.csv'

      --> into table phone1

      --> fields terminated by ','  

      --> optionally enclosed by '"' escaped by '"'

      --> lines terminated by '\n';

fields terminated by ---- 字段终止字符 
optionally enclosed by  ---- 封套符 
lines terminated by ---- 行终止符