【MOOC】【實例】—淘寶商品比價定向爬蟲

獲取淘寶搜索頁面信息，提取商品名稱和價格

1、 淘寶搜索接口

2、 翻頁處理

 

import requests
import re

## 獲取頁面
def getHTMLText(url):
    kv = {
        'cookie': 'miid=421313831459957575; _samesite_flag_=true; cookie2=1cd225d128b8f915414ca1d56e99dd42; t=5b4306b92a563cc96ffb9e39037350b4; _tb_token_=587ae39b3e1b8; cna=DmpEFqOo1zMCAdpqkRZ0xo79; unb=643110845; uc3=nk2=30mP%2BxQ%3D&id2=VWsrWqauorhP&lg2=U%2BGCWk%2F75gdr5Q%3D%3D&vt3=F8dBxdz4jRii0h%2Bs3pw%3D; csg=f54462ca; lgc=%5Cu5939zhi; cookie17=VWsrWqauorhP; dnk=%5Cu5939zhi; skt=906cb7efa634723b; existShop=MTU4MjI5Mjk4NQ%3D%3D; uc4=id4=0%40V8o%2FAfalcPHRLJCDGtb%2Fdp1gVzM%3D&nk4=0%403b07vSmMRqc2uEhDugyrBg%3D%3D; publishItemObj=Ng%3D%3D; tracknick=%5Cu5939zhi; _cc_=UIHiLt3xSw%3D%3D; tg=0; _l_g_=Ug%3D%3D; sg=i54; _nk_=%5Cu5939zhi; cookie1=AnPBkeBRJ7RXH1lHWy9jEkFiHPof0dsM6sKE2hraCKY%3D; enc=gTfBHQmDAXUW0nTwDZWT%2BXlVfPmDqVQdFSKTby%2BoWsATGTG4yqih%2FJwqG7BvGfl1N%2Bc1FeptT%2BWNjgCnd3%2FX9Q%3D%3D; __guid=154677242.2334981537288746500.1582292984682.7253; mt=ci=25_1; v=0; thw=cn; hng=CN%7Czh-CN%7CCNY%7C156; JSESSIONID=6A1CD727C830F88997EE7A11C795F670; uc1=cookie14=UoTUOLFGTPNtWQ%3D%3D&lng=zh_CN&cookie16=URm48syIJ1yk0MX2J7mAAEhTuw%3D%3D&existShop=false&cookie21=URm48syIYn73&tag=8&cookie15=URm48syIIVrSKA%3D%3D&pas=0; monitor_count=4; isg=BGRk121i5pgW-RJU8ZZzF7W5NWJW_Yhn96AFLn6F6C_yKQXzpgzI9-XL6IExt8C_; l=cBjv7QE7QsWpTNssBOCiNQhfh1_t7IRf6uSJcRmMi_5p21T_QV7OoWj0Ve96DjWhTFLB4IFj7TyTxeW_JsuKHdGJ4AadZ',
        'user-agent': "Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/63.0.3239.132 Safari/537.36"}
    try:
        r = requests.get(url, headers=kv, timeout=30)
        r.raise_for_status()
        r.encoding = r.apparent_encoding
        return r.text
    except:
        return ""

## 解析頁面信息
def parsePage(ilt, html):
    try:
        ptl = re.findall(r'\"view_price\"\:\"[\d\.]*\"', html) ## 價格 "view_price":"23.00"
        tlt = re.findall(r'\"raw_title\"\:\".*?\"', html)  ## 商品名稱 "raw_title":"蘋果數據線短iphone充電線6六8pl"
        slt = re.findall(r'\"nick\"\:\".*?\"', html)  ## 店鋪名稱 "nick":"普雷達旗艦店"
        for i in range(len(ptl)):
            price = eval(ptl[i].split(':')[1])
            title = eval(tlt[i].split(':')[1])
            nick = eval(slt[i].split(':')[1])
            ilt.append([price, title, nick])
    except:
        print('解析失敗')

## 輸出商品信息
def printGoodsList(ilt):
    tplt = '{0:4}\t{1:8}\t{2:<100}\t{3:<8}'
    print(tplt.format('序號','價格','商品名稱','店鋪名稱'))
    count = 0
    for g in ilt:
        count += 1
        print(tplt.format(count, g[0], g[1], g[2]))


def main():
    goods = '數據線'
    depth = 2  #設定向下一頁爬取地深度
    start_url = 'https://s.taobao.com/search?q=' + goods
    infoList = []
    for i in range(depth):
        try:
            url = start_url + '&s=' + str(44*i)
            html = getHTMLText(url)
            parsePage(infoList, html)
        except:
            continue
    printGoodsList(infoList)

main()

　　結果【排版有點問題】：

 

 

爬取不到任何內容處理：

原因：由於淘寶的設置，雖然可以requests爬取頁面內容，但正則表達式會匹配不到任何內容；

解決：替換headers，模擬瀏覽器向服務器發起請求

 

1、 查找瀏覽器headers（360瀏覽器）

先打開需要爬取的淘寶頁面

F12進入開發者工具

選擇Network—Name—第一條請求—Headers—Request Headers—復制cookie和user-agent

 

2、將復制的cookie和user-agent作為程序的Headers

def getHTMLText(url):
    kv = {
        'cookie': 'miid=421313831459957575; _samesite_flag_=true; cookie2=1cd225d128b8f915414ca1d56e99dd42; t=5b4306b92a563cc96ffb9e39037350b4; _tb_token_=587ae39b3e1b8; cna=DmpEFqOo1zMCAdpqkRZ0xo79; unb=643110845; uc3=nk2=30mP%2BxQ%3D&id2=VWsrWqauorhP&lg2=U%2BGCWk%2F75gdr5Q%3D%3D&vt3=F8dBxdz4jRii0h%2Bs3pw%3D; csg=f54462ca; lgc=%5Cu5939zhi; cookie17=VWsrWqauorhP; dnk=%5Cu5939zhi; skt=906cb7efa634723b; existShop=MTU4MjI5Mjk4NQ%3D%3D; uc4=id4=0%40V8o%2FAfalcPHRLJCDGtb%2Fdp1gVzM%3D&nk4=0%403b07vSmMRqc2uEhDugyrBg%3D%3D; publishItemObj=Ng%3D%3D; tracknick=%5Cu5939zhi; _cc_=UIHiLt3xSw%3D%3D; tg=0; _l_g_=Ug%3D%3D; sg=i54; _nk_=%5Cu5939zhi; cookie1=AnPBkeBRJ7RXH1lHWy9jEkFiHPof0dsM6sKE2hraCKY%3D; enc=gTfBHQmDAXUW0nTwDZWT%2BXlVfPmDqVQdFSKTby%2BoWsATGTG4yqih%2FJwqG7BvGfl1N%2Bc1FeptT%2BWNjgCnd3%2FX9Q%3D%3D; __guid=154677242.2334981537288746500.1582292984682.7253; mt=ci=25_1; v=0; thw=cn; hng=CN%7Czh-CN%7CCNY%7C156; JSESSIONID=6A1CD727C830F88997EE7A11C795F670; uc1=cookie14=UoTUOLFGTPNtWQ%3D%3D&lng=zh_CN&cookie16=URm48syIJ1yk0MX2J7mAAEhTuw%3D%3D&existShop=false&cookie21=URm48syIYn73&tag=8&cookie15=URm48syIIVrSKA%3D%3D&pas=0; monitor_count=4; isg=BGRk121i5pgW-RJU8ZZzF7W5NWJW_Yhn96AFLn6F6C_yKQXzpgzI9-XL6IExt8C_; l=cBjv7QE7QsWpTNssBOCiNQhfh1_t7IRf6uSJcRmMi_5p21T_QV7OoWj0Ve96DjWhTFLB4IFj7TyTxeW_JsuKHdGJ4AadZ',
        'user-agent': "Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/63.0.3239.132 Safari/537.36"}
    try:
        r = requests.get(url, headers=kv, timeout=30)
        r.raise_for_status()
        r.encoding = r.apparent_encoding
        return r.text
    except:
        return ""