tko/unique_cookie.py

   1 import os, random
   2
   3
   4 def unique_id(cookie_key):
   5     """
   6     Find out if remote caller has cookie set on the key.
   7     If not, set cookie on client side: evaluate this key by a random string.
   8     ( unique user identifier )
   9     In both scenarios return value of the cookie, be it old or newly set one
  10     """
  11     uid = ''
  12     ## try to retrieve uid from Cookie
  13     if 'HTTP_COOKIE' in os.environ:
  14         ## parse os.environ['HTTP_COOKIE']
  15         cookies = os.environ['HTTP_COOKIE'].split(';')
  16         key = '%s=' % cookie_key
  17         uid_cookies = [c for c in cookies if c.strip().startswith(key)]
  18
  19         if uid_cookies:
  20             assert(len(uid_cookies) == 1)
  21             uid_cookie = uid_cookies[0]
  22             uid = uid_cookie.replace(key, '')
  23
  24     if not uid:
  25         uid = str(random.random())[2:16] # random string of 14 digits
  26         set_cookie_statement = 'Set-Cookie:%s=%s;' % (cookie_key, uid)
  27         set_cookie_statement += 'expires=Thu, 26-Dec-2013 22:03:25 GMT;'
  28         print set_cookie_statement
  29
  30     return uid