forum_modules/facebookauth/authentication.py

   1 import hashlib\r
   2 from time import time\r
   3 from datetime import datetime\r
   4 from urllib import urlopen,  urlencode\r
   5 from forum.authentication.base import AuthenticationConsumer, ConsumerTemplateContext, InvalidAuthentication\r
   6 from django.utils.translation import ugettext as _\r
   7 \r
   8 import settings\r
   9 \r
  10 try:\r
  11     from json import load as load_json\r
  12 except:\r
  13     from django.utils.simplejson import JSONDecoder\r
  14 \r
  15     def load_json(json):\r
  16         decoder = JSONDecoder()\r
  17         return decoder.decode(json.read())\r
  18 \r
  19 class FacebookAuthConsumer(AuthenticationConsumer):\r
  20     \r
  21     def process_authentication_request(self, request):\r
  22         API_KEY = settings.FB_API_KEY\r
  23 \r
  24         if API_KEY in request.COOKIES:\r
  25             if self.check_cookies_signature(request.COOKIES):\r
  26                 if self.check_session_expiry(request.COOKIES):\r
  27                     return request.COOKIES[API_KEY + '_user']\r
  28                 else:\r
  29                     raise InvalidAuthentication(_('Sorry, your Facebook session has expired, please try again'))\r
  30             else:\r
  31                 raise InvalidAuthentication(_('The authentication with Facebook connect failed due to an invalid signature'))\r
  32         else:\r
  33             raise InvalidAuthentication(_('The authentication with Facebook connect failed, cannot find authentication tokens'))\r
  34 \r
  35     def generate_signature(self, values):\r
  36         keys = []\r
  37 \r
  38         for key in sorted(values.keys()):\r
  39             keys.append(key)\r
  40 \r
  41         signature = ''.join(['%s=%s' % (key,  values[key]) for key in keys]) + settings.FB_APP_SECRET\r
  42         return hashlib.md5(signature).hexdigest()\r
  43 \r
  44     def check_session_expiry(self, cookies):\r
  45         return datetime.fromtimestamp(float(cookies[settings.FB_API_KEY+'_expires'])) > datetime.now()\r
  46 \r
  47     def check_cookies_signature(self, cookies):\r
  48         API_KEY = settings.FB_API_KEY\r
  49 \r
  50         values = {}\r
  51 \r
  52         for key in cookies.keys():\r
  53             if (key.startswith(API_KEY + '_')):\r
  54                 values[key.replace(API_KEY + '_',  '')] = cookies[key]\r
  55 \r
  56         return self.generate_signature(values) == cookies[API_KEY]\r
  57 \r
  58     def get_user_data(self, key):\r
  59         request_data = {\r
  60             'method': 'Users.getInfo',\r
  61             'api_key': settings.FB_API_KEY,\r
  62             'call_id': time(),\r
  63             'v': '1.0',\r
  64             'uids': key,\r
  65             'fields': 'name,first_name,last_name,email',\r
  66             'format': 'json',\r
  67         }\r
  68 \r
  69         request_data['sig'] = self.generate_signature(request_data)\r
  70         fb_response = load_json(urlopen(settings.REST_SERVER, urlencode(request_data)))[0]\r
  71 \r
  72         return {\r
  73             'username': fb_response['first_name'] + ' ' + fb_response['last_name'],\r
  74             'email': fb_response['email']\r
  75         }\r
  76 \r
  77 class FacebookAuthContext(ConsumerTemplateContext):\r
  78     mode = 'BIGICON'\r
  79     type = 'CUSTOM'\r
  80     weight = 100\r
  81     human_name = 'Facebook'\r
  82     code_template = 'modules/facebookauth/button.html'\r
  83     extra_css = ["http://www.facebook.com/css/connect/connect_button.css"]\r
  84 \r
  85     API_KEY = settings.FB_API_KEY