Custom Auth backend with middleware - django

I tried looking at this answer, as well as using django sessions here.
The login with my custom auth works fine, but I want to validate the token on every request with middleware, and I can't figure out how to store the token so that it may be accessed from both the middleware as well as views.
I tried storing a session variable from my auth backend, but I would always get a key error when trying to access it from my views.
Is there a good way to do this?
Thanks!
class MyAuthBackend(object):
supports_inactive_user = False
supports_object_permissions = False
supports_anonymous_user = False
def authenticate(self, username=None, password=None):
# This makes a call to my API to varify login, then return token if valid. I need to make login_valid accessible to my middleware and views.
login_valid = auth.login(username,password)
if login_valid:
try:
user = User.objects.get(username=username)
except User.DoesNotExist:
user = User(username=username, password='never_used')
user.is_active = True
user.save()
return user
return None
def get_user(self, user_id):
try:
return User.objects.get(pk=user_id)
except User.DoesNotExist:
return None
class MyAuthMiddleware(object):
def process_request(self, request):
if not request.user.is_anonymous():
# API call to my backend to check if token is still valid. If not, return to login page.
token_variable = ???????????
if isTokenStillValid(token_variable):
return
else:
return HttpResponseRedirect('/accounts/login/?next=%s' % request.path)

Are you using the default django.contrib.auth login view for logging in? It seems to completely clear the session during the login process (which happens after your authentication backend is called, in contrib.auth.login function, described here).
I think you might either try to write your own login view, with an alternative login function that preserves the auth token, or store the token somewhere else (database table, cache system). The latter might make it difficult to allow multiple simultaneous logins for one user.

Related

Django : How can we custom login_required decorator?

I want to write a decorator like the login_required decorator of Django to check the Azure AD authentication and the Django authentication at the same time. If one of the two is not true, it redirects to the login page.
For the authentication, I used the tutorial (https://learn.microsoft.com/en-us/graph/tutorials/python). I do not how to deal with groups and permissions since I use Azure AD authentication. So I take the username and surname from the token that comes from the Azure Authentication and with this two infos, I create an user in the User Django models. I know it is not the best idea, but I can start to play with groups and permissions.
The django authentication is automatic without that the user create it. It is done in the callback function.
def callback(request):
# Make the token request
result = get_token_from_code(request)
#Get the user's profile
user = get_user(result['access_token'])
# Store user
store_user(request, user)
# Get user info
# user attribute like displayName,surname,mail etc. are defined by the
# institute incase you are using single-tenant. You can get these
# attribute by exploring Microsoft graph-explorer.
username = user['displayName']
password = user['surname']
email = user['mail']
try:
# if use already exist
user = User.objects.get(username=username)
except User.DoesNotExist:
# if user does not exist then create a new user
user = User.objects.create_user(username,email,password)
user.save()
user = authenticate(username=username,password=password)
if user is not None:
login(request,user)
messages.success(request,"Success: You were successfully logged in.")
return redirect('home')
return redirect('home')
If I want to check if the user is authenticated by Azure AD. From the tutorial, I should do something like that :
if request.session.get('user').get('is_authenticated') :
But I do not know how to combine with the django authentication to check both. Anyone can help me
Thanks
simplest way would be to use the user_passes_test decorator to make your own function and apply that as a decorator to your views as per the docs
from django.contrib.auth.decorators import user_passes_test
def check_azure(user):
# so something here to check the azure login which should result in True/False
return #theResult of your check
#user_passes_test(check_azure)
def my_view(request):
...
Here is my solution :
from django.shortcuts import redirect
def authenticated_user(view_func) :
def wrapper_func(request, *args, **kwargs):
if request.user.is_authenticated and request.session.get('user').get('is_authenticated') :
return view_func(request, *args, **kwargs)
else :
return redirect('login')
return wrapper_func

user.is_authenticated returns False with custom backend

I've created a custom backend for my application in order to let people log in with ldap. Seems like everything is working, apart from one thing:
I am checking if "user.is_authenticated" in template to show "Log out" button for authenticated users, and it seems to return false all the time.
I am using standard django LoginView. Before I added my custom backend it all worked just fine, and I only rewrote the "authenticate()" function the way it says in django docs.
How could I fix it?
My backend is:
class MyBackEnd(object):
"""
This is the custom backend to authenticate the user in the DB.
if this authentication fais then django default authentication will get called
"""
def authenticate(self, request, username, password):
#here comes server address and search templates
try:
return User.objects.get(username=username)
except User.DoesNotExist:
try:
l = ldap.initialize(server)
l.protocol_version = 3
l.set_option(ldap.OPT_REFERRALS, 0)
l.simple_bind_s(username, password)
r = l.search(base, scope, filter, attrs)
type, user = l.result(r, 60)
if len(user) == 1:
user = User.objects.create_user(username=username, password=password)
user.save()
return user
except:
print("Failed to connect with ldap")
return None
def get_user(self, user_id):
try:
return User.objects.get(username=user_id)
except User.DoesNotExist:
return None
In function get_user:
return User.objects.get(username=user_id)
Is username stands for primary key in User model?
Try to replace following line by this:
return User.objects.get(pk=user_id)

Custom django authentication backend doesn't log user in first time, but works second time

So I'm using Rdio to login and create users, and wrote a backend to handle its oauth. The first time you try to sign in using Rdio, it creates a user and an attached Rdio user, but it doesn't create a session and return the session cookie.
The flow is like any oauth2 flow: you press a button on my app, it redirects w/ get params to Rdio, and Rdio calls a callback view on my app (along with a code in the GET params). In that callback view, I call authenticate:
class RdioCallbackView(View):
def get(self, request):
""" here, you need to create and auth a django user and create and tie the rdio user's stuff to it """
if request.user.is_authenticated() == False:
try:
rdio_code = request.GET['code']
except KeyError:
return redirect(reverse('login'))
# authenticate
user = auth.authenticate(rdio_code=rdio_code)
if user is not None and user.is_active:
auth.login(request, user)
else:
return render(request, 'home/login.html', {'rdio_url': create_rdio_auth_url(), 'message': "That code didn't seem to work"})
else:
# user exists!
user = request.user
return HttpResponseRedirect(reverse('the-next-view'))
The custom auth backend looks like this:
class RdioBackend(object):
def authenticate(self, rdio_code=None):
token_info = exchange_rdio_code(rdio_code)
try:
access_token = token_info['access_token']
refresh_token = token_info['refresh_token']
except KeyError:
return None
except TypeError:
# the code was probably already used.
return None
rdio_user_dict = get_rdio_user_for_access_token(access_token)
rdio_key = rdio_user_dict['key']
try:
rdio_user = RdioUser.objects.get(rdio_id=rdio_key)
rdio_user.access_token = access_token
rdio_user.refresh_token = refresh_token
rdio_user.save()
user = rdio_user.user
except RdioUser.DoesNotExist:
user = User.objects.create(username=rdio_key)
user.set_unusable_password()
rdio_user = RdioUser.objects.create(
rdio_id = rdio_key,
access_token = access_token,
refresh_token = token_info['refresh_token'],
user = user,
)
return user
def get_user(self, user_id):
try:
return User.objects.get(pk=user_id)
except User.DoesNotExist:
return None
And that's where things get weird. It doesn't seem to make a new Session object, and definitely doesn't return a session cookie. However, when I go back and do the Rdio login again for a second time, it returns a session cookie, makes the session on the backend, and login and auth work perfectly.
And I think my AUTHENTICATION_BACKENDS settings is right:
AUTHENTICATION_BACKENDS = (
'appname.backend.RdioBackend',
'django.contrib.auth.backends.ModelBackend',
)
Edit: More possibly relevant info:
The views that it's redirecting to have a LoginRequiredMixin:
class LoginRequiredMixin(object):
#classmethod
def as_view(cls, **initkwargs):
view = super(LoginRequiredMixin, cls).as_view(**initkwargs)
return login_required(view)
And in RdioCallbackView, when I change the final line from return HttpResponseRedirect(reverse('the-next-view')) to instead just serve the template directly with return render(request, 'path/to.html', param_dict), it does serve the cookie and make a sessionid, but then it deletes it from the DB and from the browser the moment I navigate away from that screen.
This might be the dumbest bug ever. It turns out that if you create a user without a password, you don't need to call user.set_unusable_password(). And if you do call user.set_unusable_password(), it somehow messes with any auth you do (even AFTER you call that).
So to fix this, I just got rid of the call to user.set_unusable_password() in my custom django auth backend.

How to establish Django session using Tastypie ApiKeyAuthentication?

I want to use Tastypie's ApiKeyAuthentication to authenticate a request and then establish a session for the user within a Django view. I have username and api_key for the user. I do not have the user's password. This is the code I currently have:
class ApiKeyPlusWebAuthentication(ApiKeyAuthentication):
def is_authenticated(self, request, **kwargs):
isAuthenticated = super(ApiKeyPlusWebAuthentication, self).is_authenticated(request, **kwargs)
if isAuthenticated:
print request.user.email
return isAuthenticated
#login for access from UIWebView
def login_usingApiKeyAuthentication(request):
auth = ApiKeyPlusWebAuthentication(request)
if auth.is_authenticated(request):
print 'authenticated'
login(request, request.user)
return redirect(reverse(view_name))
else:
print 'NOT authenticated'
messages.error(request, MESSAGE_INVALID_LOGIN)
fail_redirect = redirect(reverse('login'))
return fail_redirect
I am getting an error 'User' object has no attribute 'backend'. This is because I haven't called authenticate(user, password). I am using the Django default authentication backend.
In this scenario, I only have APIKey associated with the user and don't have the raw password for authentication.
One way to handle this may be to create custom authentication backend that bypasses password requirement. However, registering a "password-less" authentication backend in settings.py seems like a hack prone to security breakdown.
So, how can I use ApiKeyAuthentication and then authenticate & login the user in Django establishing a session?
I found a solution to set the backend in another post. You can set the custom backend directly on the user object.
from django.contrib.auth.backends import ModelBackend
from django.contrib.auth.models import User
class PasswordlessAuthBackend(ModelBackend):
"""Log in to Django without providing a password.
"""
def authenticate(self, username=None):
try:
return User.objects.get(username=username)
except User.DoesNotExist:
return None
def get_user(self, user_id):
try:
return User.objects.get(pk=user_id)
except User.DoesNotExist:
return None
#csrf_exempt
def login_uiwebview(request):
auth = ApiKeyPlusWebAuthentication(request)
if auth.is_authenticated(request):
view_name = request.POST.get('view_name')
request.user.backend = 'app.views.PasswordlessAuthBackend'
login(request, request.user)
return redirect(view_name)
else:
print 'NOT authenticated'
messages.error(request, MESSAGE_INVALID_LOGIN)
fail_redirect = redirect(reverse('login'))
return fail_redirect

Test that user was logged in successfully

How can I test that a user is logged in after submitting the registration form?
I tried the following but it returns True even before I added the login logic to my registration view.
def test_that_user_gets_logged_in(self):
response = self.client.post(reverse('auth-registration'),
{ 'username':'foo',
'password1':'bar',
'password2':'bar' } )
user = User.objects.get(username='foo')
assert user.is_authenticated()
The code that's being tested:
class RegistrationView(CreateView):
template_name = 'auth/registration.html'
form_class = UserCreationForm
success_url = '/'
def auth_login(self, request, username, password):
'''
Authenticate always needs to be called before login because it
adds which backend did the authentication which is required by login.
'''
user = authenticate(username=username, password=password)
login(request, user)
def form_valid(self, form):
'''
Overwrite form_valid to login.
'''
#save the user
response = super(RegistrationView, self).form_valid(form)
#Get the user creditials
username = form.cleaned_data['username']
password = form.cleaned_data['password1']
#authenticate and login
self.auth_login(self.request, username, password)
return response
You can use the get_user method of the auth module. It says it wants a request as parameter, but it only ever uses the session attribute of the request. And it just so happens that our Client has that attribute.
from django.contrib import auth
user = auth.get_user(self.client)
assert user.is_authenticated
This is not the best answer. See https://stackoverflow.com/a/35871564/307511
Chronial has given
an excellent example on how to make this assertion below. His answer
better than mine for nowadays code.
The most straightforward method to test if a user is logged in is by testing the Client object:
self.assertIn('_auth_user_id', self.client.session)
You could also check if a specific user is logged in:
self.assertEqual(int(self.client.session['_auth_user_id']), user.pk)
As an additional info, the response.request object is not a HttpRequest object; instead, it's an ordinary dict with some info about the actual request, so it won't have the user attribute anyway.
Also, testing the response.context object is not safe because you don't aways have a context.
Django's TestClient has a login method which returns True if the user was successfully logged in.
The method is_authenticated() on the User model always returns True. False is returned for request.user.is_authenticated() in the case that request.user is an instance of AnonymousUser, which is_authenticated() method always returns False.
While testing you can have a look at response.context['request'].user.is_authenticated().
You can also try to access another page in test which requires to be logged in, and see if response.status returns 200 or 302 (redirect from login_required).
Where are you initialising your self.client? What else is in your setUp method? I have a similar test and your code should work fine. Here's how I do it:
from django.contrib.auth.models import User
from django.test import TestCase
from django.test.client import Client
class UserTestCase(TestCase):
def setUp(self):
self.client = Client()
def testLogin(self):
print User.objects.all() # returns []
response = self.client.post(reverse('auth-registration'),
{ 'username':'foo',
'password1':'bar',
'password2':'bar' } )
print User.objects.all() # returns one user
print User.objects.all()[0].is_authenticated() # returns True
EDIT
If I comment out my login logic, I don't get any User after self.client.post(. If you really want to check if the user has been authenticated, use the self.client to access another url which requires user authentication. Continuing from the above, access another page:
response = self.client.get(reverse('another-page-which-requires-authentication'))
print response.status_code
The above should return 200 to confirm that the user has authenticated. Anything else, it will redirect to the login page with a 302 code.
There is another succinct way, using wsgi_request in response:
response = self.client.post('/signup', data)
assert response.wsgi_request.user.is_authenticated()
and #Chronial 's manner is also available with wsgi_request:
from django.contrib import auth
user = auth.get_user(response.wsgi_request)
assert user.is_authenticated()
Because response.wsgi_request object has a session attribute.
However, I think using response.wsgi_request.user is more simple.