[snowy] Use a session variable for redirection after login

[Sanford Armstrong <sharm src gnome org>]

commit 8fd1c232384f772164254ab1591354259e930128
Author: Leon Handreke <leon handreke gmail com>
Date:   Mon Nov 15 11:57:31 2010 +0100

    Use a session variable for redirection after login
    
    Doing this fixes OAuth for some more unusual authentication flows,
    such as creating a new account or using username/password to log in.
    
    This fixes bug #633067 and #629853.

 accounts/middleware.py |   13 +++++++++++++
 accounts/views.py      |    7 ++++++-
 settings.py            |    1 +
 3 files changed, 20 insertions(+), 1 deletions(-)
---
diff --git a/accounts/middleware.py b/accounts/middleware.py
index e4bf2db..567966e 100644
--- a/accounts/middleware.py
+++ b/accounts/middleware.py
@@ -17,6 +17,9 @@
 
 from django.middleware.common import CommonMiddleware
 from django.utils import translation
+from django.http import HttpResponseRedirect
+
+from django.conf import settings
 
 class LocaleMiddleware:
     def process_view(self, request, view_func, view_args, view_kwargs):
@@ -25,3 +28,13 @@ class LocaleMiddleware:
             if profile.language:
                 translation.activate(profile.language)
         return None
+
+class LoginRedirectMiddleware:
+    def process_request(self, request):
+        if request.path == settings.LOGIN_REDIRECT_URL and \
+        request.session.get('login_complete_redirect', None) and \
+        request.user.is_authenticated():
+            redirect_to = request.session['login_complete_redirect']
+            # do not redirect the next time the user visits LOGIN_REDIRECT_URL
+            request.session['login_complete_redirect'] = None
+            return HttpResponseRedirect(redirect_to)
diff --git a/accounts/views.py b/accounts/views.py
index a9d48ac..36f7181 100644
--- a/accounts/views.py
+++ b/accounts/views.py
@@ -19,10 +19,11 @@ from django.utils.translation import ugettext_lazy as _
 
 from django.contrib.auth.forms import UserChangeForm, PasswordChangeForm
 from django.contrib.auth.models import User
-from django.contrib.auth import authenticate, login
+from django.contrib.auth import authenticate, login, REDIRECT_FIELD_NAME
 from django.contrib.auth.decorators import login_required
 from django.core.urlresolvers import reverse
 from django.contrib import messages
+from django.views.decorators.csrf import csrf_exempt
 
 from django.shortcuts import render_to_response
 from django.http import HttpResponseRedirect, HttpResponseNotAllowed
@@ -85,6 +86,10 @@ def openid_registration(request, template_name='registration/registration_form.h
 def openid_begin(request, **kwargs):
     """A wrapper view around the login_begin view in
     django_openid_auth that features a nicer error display"""
+    redirect_to = request.REQUEST.get(REDIRECT_FIELD_NAME, '')
+    if redirect_to != '':
+        request.session['login_complete_redirect'] = redirect_to
+
     return django_openid_auth.views.login_begin(request, render_failure=render_openid_failure,
                                                    **kwargs)
 
diff --git a/settings.py b/settings.py
index fec54e8..e21dc06 100644
--- a/settings.py
+++ b/settings.py
@@ -97,6 +97,7 @@ MIDDLEWARE_CLASSES = [
     'django.middleware.locale.LocaleMiddleware',
     'snowy.accounts.middleware.LocaleMiddleware',
     'django.contrib.auth.middleware.AuthenticationMiddleware',
+    'snowy.accounts.middleware.LoginRedirectMiddleware',
     'django.middleware.transaction.TransactionMiddleware',
     #'reversion.middleware.RevisionMiddleware',
     'recaptcha_django.middleware.ReCaptchaMiddleware',