Automatic acquisition and expiration of cookies through web crawlers (detailed tutorial)

This article mainly introduces the implementation method of automatic acquisition of cookies and automatic update of expired cookies by web crawlers. Friends in need can refer to the following

This article implements automatic acquisition of cookies and automatic update of cookies when expired.

A lot of information on social networking sites requires logging in to get it. Take Weibo as an example. Without logging in, you can only see the top ten Weibo posts of big Vs. To stay logged in, cookies are required. Take logging in to www.weibo.cn as an example:

Enter in chrome: http://login.weibo.cn/login/

Analysis Control When the header request from the station is returned, you will see several sets of cookies returned by weibo.cn.

Implementation steps:

1, use selenium to automatically log in to obtain cookies, save them to a file;

2, read cookie, compare the validity period of the cookie, and if it expires, perform step 1 again;

3, when requesting other web pages, fill in the cookie to maintain the login status.

1, Get cookies online

Use selenium PhantomJS to simulate browser login and obtain cookies;

There are usually multiple cookies, and the cookies are stored one by one with the .weibo suffix. document.

def get_cookie_from_network():
 from selenium import webdriver
 url_login = 'http://login.weibo.cn/login/' 
 driver = webdriver.PhantomJS()
 driver.get(url_login)
 driver.find_element_by_xpath('//input[@type="text"]').send_keys('your_weibo_accout') # 改成你的微博账号
 driver.find_element_by_xpath('//input[@type="password"]').send_keys('your_weibo_password') # 改成你的微博密码
 driver.find_element_by_xpath('//input[@type="submit"]').click() # 点击登录
 # 获得 cookie信息
 cookie_list = driver.get_cookies()
 print cookie_list
 cookie_dict = {}
 for cookie in cookie_list:
  #写入文件
  f = open(cookie['name']+'.weibo','w')
  pickle.dump(cookie, f)
  f.close()
  if cookie.has_key('name') and cookie.has_key('value'):
   cookie_dict[cookie['name']] = cookie['value']
 return cookie_dict

2, get cookies from files

Traverse files ending with .weibo, that is, cookie files, from the current directory. Use pickle to unpack it into a dict, compare the expiry value with the current time, and return empty if it expires;

def get_cookie_from_cache():
 cookie_dict = {}
 for parent, dirnames, filenames in os.walk('./'):
  for filename in filenames:
   if filename.endswith('.weibo'):
    print filename
    with open(self.dir_temp + filename, 'r') as f:
     d = pickle.load(f)
     if d.has_key('name') and d.has_key('value') and d.has_key('expiry'):
      expiry_date = int(d['expiry'])
      if expiry_date > (int)(time.time()):
       cookie_dict[d['name']] = d['value']
      else:
       return {}
 return cookie_dict

3, if the cached cookie expires, obtain the cookie from the network again

def get_cookie():
 cookie_dict = get_cookie_from_cache()
 if not cookie_dict:
  cookie_dict = get_cookie_from_network()
 return cookie_dict

4, Use cookies to request other Weibo homepages

def get_weibo_list(self, user_id):
 import requests
 from bs4 import BeautifulSoup as bs
 cookdic = get_cookie()
 url = 'http://weibo.cn/stocknews88' 
 headers = {'User-Agent': 'Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/31.0.1650.57 Safari/537.36'}
 timeout = 5
 r = requests.get(url, headers=headers, cookies=cookdic,timeout=timeout)
 soup = bs(r.text, 'lxml')
 ...
 # 用BeautifulSoup 解析网页
 ...

The above is what I compiled for everyone. I hope it will be helpful to everyone in the future.

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