淘宝商品比价定向爬虫

功能描述

目标：获取淘宝搜索页面的信息，提取其中名称和价格
理解：淘宝搜索接口翻页的处理
技术路线：requests+re

搜索"书包"，浏览器起始页链接：
https://s.taobao.com/search?q=书包&commend=all&ssid=s5e&search_type=item&sourceId=tb.index&spm=a21bo.2017.201856taobaoitem.1&ie=utf8&initiative_id=tbindexz_20170306

第二页：

https://s.taobao.com/search?q=书包&commend=all&ssid=s5e&search_type=item&sourceId=tb.index&spm=a21bo.2017.201856taobaoitem.1&ie=utf8&initiative_id=tbindexz_20170306&bcoffset=4&ntoffset=4&p4ppushleft=1%2C48&s=44

每一页有44个商品。

程序的结构

步骤1 提交商品搜索请求，循环获取页面
步骤2 对于每个页面，提取商品名称和价格信息
步骤3 将信息输出在屏幕上

 1 import requests
 2 import re
 3 def getHTMLText(url):
 4     try:
 5         r = requests.get(url, timeout = 30)
 6         r.raise_for_status()
 7         r.encoding = r.apparent_encoding
 8         return r.text
 9     except:
10         return ""
11 def parsePage(goodsList, html):
12     try:
13         priseList = re.findall(r'"view_price":"[d.]*"',html)
14         titleList = re.findall(r'"raw_title":".*?"', html)
15         for i in range(len(priseList)):
16             prise = eval(priseList[i].split(':')[1])
17             title = eval(titleList[i].split(':')[1])
18             goodsList.append([prise, title])
19     except:
20         print("")
21 def printGoodsList(goodsList):
22     tplt = "{:4}	{:8}	{:16}"
23     print(tplt.format("序号", "价格", "商品名称"))
24     count = 0
25     for g in goodsList:
26         count = count + 1
27         print(tplt.format(count, g[0], g[1]))
28 def main():
29     goods = '书包'
30     depth = 3
31     stard_url = 'https://s.taobao.com/search?q=' + goods
32     infoList = []
33     for i in range(depth):
34         try:
35             url = stard_url + '&s' + str(44 * i)
36             html = getHTMLText(url)
37             parsePage(infoList, html)
38         except:
39             continue
40     printGoodsList(infoList)
41 main()

输出（部分）：