Improve handling of iframe applications - get session key/uid from GE…

…T if not in session if internal=False. Also ensure cookies expire properly.

facebook/djangofb/__init__.py

@@ -1,5 +1,5 @@
 import re
-
+import datetime
 import facebook
 
 from django.http import HttpResponse, HttpResponseRedirect
@@ -205,12 +205,19 @@ def __init__(self, api_key=None, secret_key=None, app_name=None, callback_path=N
 
     def process_request(self, request):
         _thread_locals.facebook = request.facebook = Facebook(self.api_key, self.secret_key, app_name=self.app_name, callback_path=self.callback_path, internal=self.internal, proxy=self.proxy)
-        if not self.internal and 'facebook_session_key' in request.session and 'facebook_user_id' in request.session:
-            request.facebook.session_key = request.session['facebook_session_key']
-            request.facebook.uid = request.session['facebook_user_id']
+        if not self.internal:
+            if 'fb_sig_session_key' in request.GET and 'fb_sig_user' in request.GET:
+                request.facebook.session_key = request.session['facebook_session_key'] = request.GET['fb_sig_session_key']
+                request.facebook.uid = request.session['fb_sig_user'] = request.GET['fb_sig_user']
+            elif request.session.get('facebook_session_key', None) and request.session.get('facebook_user_id', None):
+                request.facebook.session_key = request.session['facebook_session_key']
+                request.facebook.uid = request.session['facebook_user_id']
 
     def process_response(self, request, response):
         if not self.internal and request.facebook.session_key and request.facebook.uid:
             request.session['facebook_session_key'] = request.facebook.session_key
             request.session['facebook_user_id'] = request.facebook.uid
+            if request.facebook.session_key_expires:
+                expiry = datetime.datetime.fromtimestamp(request.facebook.session_key_expires)
+                request.session.set_expiry(expiry)
         return response