Added support for Google+

README

@@ -14,8 +14,19 @@ Currently supported, simultaneous auth backends:
 -------------------------------------------------
 - Usual Django login
 - Login with Facebook (using Facebook Graph API)
+- Login with Google+
 
 Installing (Tryout)
 -------------------
 Just clone this repo and hit 'runserver', to try this out.
 
+For Facebook app:
+i) Create a facebook app from the facebook developers site (with redirect_uri as '/facebook/login/')
+ii) Update settings.py with 'FACEBOOK_APP_ID' and 'FACEBOOK_APP_SECRET'.
+
+For Google+ app:
+i) Create a new application from the Google APIs Console (https://code.google.com/apis/console/),
+with redirect uri specified to '/googleplus/login/' of your server.
+ii) Use the 'client_id' and 'client_secret' obtained from step i, and make
+appropriate changes in settings.py to update 'GOOGLEPLUS_CLIENT_ID' and
+'GOOGLEPLUS_CLIENT_SECRET'.

facebook/views.py

@@ -91,7 +91,8 @@ def _create_or_update_facebook_user(profile, access_token, expires):
     except FacebookUser.DoesNotExist:
         user = User.objects.create( \
             first_name=profile['first_name'],
-            last_name=profile['last_name']
+            last_name=profile['last_name'],
+            username='fb_' + profile['id']
         )
         user_is_created = True
 

googleplus/backends.py

@@ -0,0 +1,16 @@
+from django.contrib.auth.models import User
+
+class GooglePlusBackend:
+    supports_inactive_user = False
+
+    def authenticate(self, googleplus_user=None):
+        if googleplus_user is not None:
+            return googleplus_user.user
+        else:
+            return None
+
+    def get_user(self, user_id):
+        try:
+            return User.objects.get(id=user_id)
+        except User.DoesNotExist:
+            return None

googleplus/models.py

@@ -0,0 +1,15 @@
+from django.contrib.auth.models import User
+from django.db import models
+
+class GooglePlusUser(models.Model):
+    """Stores Google+ user specific details. 
+    """
+    user = models.OneToOneField(User)
+    access_token = models.TextField(db_index=True)
+    expiry_at = models.DateTimeField(null=True)
+    googleplus_id = models.CharField(max_length=100, unique=True, db_index=True)
+    googleplus_display_name = models.CharField(max_length=100, unique=True, db_index=True)
+
+    def __unicode__(self):
+        return unicode(self.id) + u' | ' + unicode(self.googleplus_id)
+

googleplus/tests.py

@@ -0,0 +1,16 @@
+"""
+This file demonstrates writing tests using the unittest module. These will pass
+when you run "manage.py test".
+
+Replace this with more appropriate tests for your application.
+"""
+
+from django.test import TestCase
+
+
+class SimpleTest(TestCase):
+    def test_basic_addition(self):
+        """
+        Tests that 1 + 1 always equals 2.
+        """
+        self.assertEqual(1 + 1, 2)

googleplus/urls.py

@@ -0,0 +1,5 @@
+from django.conf.urls.defaults import patterns, include, url
+
+urlpatterns = patterns('',
+    url(r'login/$', 'googleplus.views.login_handler'),
+)

googleplus/utils.py

@@ -0,0 +1,22 @@
+import json
+import urllib
+import urlparse
+
+def graph_api(path, params, method="GET"):
+    """Invokes the Google+ API.
+    Returns the response as python dictionary.
+    """
+    # Construct the API url.
+    base_url = 'https://www.googleapis.com/plus/v1/'
+    url = urlparse.urljoin(base_url, path)
+
+    # Invoke the Google+ API with the specified method. 
+    if method.upper() == "GET":
+        req = urllib.urlopen(url + '?' + urllib.urlencode(params))
+    elif method.upper() == "POST":
+        req = urllib.urlopen(url, urllib.urlencode(params))
+
+    response = req.read()
+    response_dict = json.loads(response)
+
+    return response_dict

googleplus/views.py

@@ -0,0 +1,119 @@
+from django.conf import settings
+from django.contrib import messages
+from django.contrib.auth import authenticate, login
+from django.contrib.auth.models import User
+from django.contrib.sites.models import Site
+from django.http import HttpResponseRedirect
+from django.shortcuts import render_to_response
+from django.template.context import RequestContext
+import datetime
+import json
+import urllib
+import urlparse
+
+from googleplus import utils
+from googleplus.models import GooglePlusUser
+
+GOOGLEPLUS_LOGIN_URL = '/googleplus/login/'
+REDIRECT_URI = urlparse.urljoin( \
+    'http://' + Site.objects.get_current().domain, GOOGLEPLUS_LOGIN_URL
+)
+
+def login_handler(request):
+    """Google+ OAuth2 login handler.
+    """
+    if request.user.is_authenticated():
+        return HttpResponseRedirect(settings.LOGIN_REDIRECT_URL)
+
+    if 'error' in request.GET:
+        messages.add_message(request, messages.ERROR, 
+                             request.GET['error'])
+        return HttpResponseRedirect(settings.LOGIN_REDIRECT_URL)
+    elif 'code' in request.GET:
+        params = { \
+            'client_id': settings.GOOGLEPLUS_CLIENT_ID, \
+            'redirect_uri': REDIRECT_URI, \
+            'client_secret': settings.GOOGLEPLUS_CLIENT_SECRET, \
+            'code': request.GET['code'], \
+            'grant_type': 'authorization_code', \
+        }
+        req = urllib.urlopen('https://accounts.google.com/o/oauth2/token',
+            urllib.urlencode(params)
+        )
+        if req.getcode() != 200:
+            response = render_to_response('500.html', {}, \
+                               context_instance=RequestContext(request))
+            response.status_code = 500
+            return response
+
+        response = req.read()
+        response_query_dict = json.loads(response)
+        access_token = response_query_dict['access_token']
+        expires_in = response_query_dict['expires_in']
+
+        profile = utils.graph_api('people/me', {'access_token': access_token})
+
+        googleplus_user = _create_or_update_googleplus_user(profile, access_token, expires_in)
+
+        user = authenticate(googleplus_user=googleplus_user)
+        if user is not None:
+            if user.is_active:
+                login(request, user)
+                request.session.set_expiry(googleplus_user.expiry_at)
+                if 'next' in request.GET:
+                    return HttpResponseRedirect(request.GET['next'])
+                return HttpResponseRedirect(settings.LOGIN_REDIRECT_URL)
+            else:
+                messages.add_message(request, messages.ERROR, "Account disabled.")
+        else:
+            messages.add_message(request, messages.ERROR, "Login failed.")
+    else:
+        params = { \
+            'client_id': settings.GOOGLEPLUS_CLIENT_ID, \
+            'redirect_uri': REDIRECT_URI, \
+            'scope': 'https://www.googleapis.com/auth/plus.me', \
+            'response_type': 'code', \
+        }    
+        return HttpResponseRedirect('https://accounts.google.com/o/oauth2/auth?' +
+            urllib.urlencode(params)
+        )
+
+def _create_or_update_googleplus_user(profile, access_token, expires_in):
+    """Creates or updates a Google+ user profile in local database.
+    """
+    user_is_created = False
+    try:
+        googleplus_user = GooglePlusUser.objects.get(googleplus_id=profile['id'])
+    except GooglePlusUser.DoesNotExist:
+        first_name, last_name = _get_first_and_last_name(profile['displayName'])
+        user = User.objects.create( \
+            first_name=first_name,
+            last_name=last_name,
+            username='googleplus_' + profile['id']
+        )
+        user_is_created = True
+
+    if user_is_created:
+        googleplus_user = GooglePlusUser()
+        googleplus_user.googleplus_id = profile['id']
+        googleplus_user.user = user
+    else:
+        first_name, last_name = _get_first_and_last_name(profile['displayName'])
+        googleplus_user.user.first_name = first_name
+        googleplus_user.last_name = last_name
+
+    googleplus_user.googleplus_display_name = profile['displayName']
+    googleplus_user.access_token = access_token
+    googleplus_user.expiry_at = datetime.datetime.now() + \
+        datetime.timedelta(seconds=int(expires_in))    
+    googleplus_user.save()
+
+    return googleplus_user
+
+def _get_first_and_last_name(display_name):
+    try:
+        first_name, last_name = display_name.strip().rsplit(' ', 1)
+    except ValueError:
+        first_name = display_name
+        last_name = ''
+    return first_name, last_name

settings.py

@@ -123,6 +123,7 @@
     # 'django.contrib.admindocs',
     'account',
     'facebook',
+    'googleplus',
 )
 
 # A sample logging configuration. The only tangible logging
@@ -158,11 +159,15 @@
 AUTHENTICATION_BACKENDS = (
     'django.contrib.auth.backends.ModelBackend',
     'facebook.backends.FacebookBackend',
+    'googleplus.backends.GooglePlusBackend',
 )
 
 LOGIN_URL = '/login/'
 LOGIN_REDIRECT_URL = '/'
 
-FACEBOOK_APP_ID = '222026897833284'
-FACEBOOK_APP_SECRET = '175712afcb64656ca488844202394e0b'
+FACEBOOK_APP_ID = ''
+FACEBOOK_APP_SECRET = ''
 FACEBOOK_APP_PERMISSIONS = ''
+
+GOOGLEPLUS_CLIENT_ID = ''
+GOOGLEPLUS_CLIENT_SECRET = ''

templates/account/index.html

@@ -20,6 +20,7 @@ <h3>You are not authenticated. Login to proceed.</h3>
 	<div class="login">
 		<div class="login-option"><a href="{% url 'account.views.login_handler' %}">Usual Login</div>
 		<div class="login-option"><a href="{% url 'facebook.views.login_handler' %}">Login using Facebook</div>
+		<div class="login-option"><a href="{% url 'googleplus.views.login_handler' %}">Login with Google+</div>
 	</div>
 {% endif %}
 {% endblock content %}

urls.py

@@ -18,4 +18,5 @@
     url(r'^login/$', 'account.views.login_handler'),
     url(r'^logout/$', 'account.views.logout_handler'),
     url(r'^facebook/', include('facebook.urls')),
+    url(r'^googleplus/', include('googleplus.urls')),
 )