Using Account Auth to verify if logged in yet - python

I have a small view:
def AccountHome(request):
return render(request, 'myapp/account/accounthome.html', {
})
In previous views, I've used:
if user is not None and user.is_active
to check if a user is already authenticated or not when using native form classes like: AuthenticationForm for example when logging in a user.
But on this view I am not using that, is there someway to validate whether a user is logged in or not without using this AuthenticationForm classagain? Thisviews purpose is to show the homescreen when logged in, so it seems non-intuitive to extend thatAuthenticationForm` class again.
Any help or thoughts?
Thanks

Use is_authenticated() method
Like this: if request.user.is_authenticated():
You can find the reference here: https://docs.djangoproject.com/en/dev/ref/contrib/auth/#methods

Related

Need help understanding Django authentication code

Code from views.py:
from django.contrib.auth.decorators import login_required
#login_required
def index(request):
user = request.user
posts = Post.objects.filter(user=user)
I can't understand the inline #login_required. Why should we use this decorator?
And what about user = request.user? In this project, we hadn't created a model named user.
Please explain this to me. Thanks a lot!
In this code I can't understand inline #login_required Why should we use the decorator
The #login_required decorator does exactly what it says: it requires a user to log in when accessing the route associated with this view.
And user=request.user user ?? In this project, we hadn't created models named user.
Django defines a User model fore you.
For more details about the default authentication and authorization system, read the documentation. Googling something like "django login_required" gives a wealth of information.
The logic behind this function is to achieve that only the logged-in user has access to the posts he wrote himself: all http requests contain the id of the user: if he is not logged in, he is identified as anonymous, otherwise as user.
To get his identification, you call request.user and then pass it to the query to call his posts.
Therefore :
neither an anonymous user nor another user can get access to the full list of posts of a third user.

Create public profiles for users in django

I created a profile view for users and I want everyone to be able to see it without having to log in
But when I click on the profile while not having logged in, it automatically logs into the account of the user I clicked on!
How can I fix it?
This is the view
def public_profile(request, username):
user =
User.objects.get(username=username)
return render(request, 'users/public_profile.html', {"user": user})
This is the url
path('<str:username>/profile/', public_profile, name='public-profile'),
It likely does not log in. But some context processors will add certain elements to the context. For example the django.contrib.auth.context_processors.auth.auth context processor will add a value for the 'user' key to the context if the user is logged in. A template that thus works with {{ user }}, might assume this is the logged in user.
You therefore better pass the user you want to show under a different name, for example profile:
from django.shortcuts import get_object_or_404
def public_profile(request, username):
user = get_object_or_404(User, username=username)
return render(request, 'users/public_profile.html', {'profile' : user})
As Willem Van Onsem says, the user variable is used by the Authentication middleware to represent the current logged user, so your user object is replaced with that. Try changing the name of the variable you use.

How to make a login view for django custom user?

I have made a custom user model using the AbstractUser , removed the username and replaced it with email and extended the model, tried creating superuser and it worked and also created some users by a signup form , logged in the admin interface and it worked however when tried to create a login form for the users it fails
I tried this but it didn't work
def LoginView(request):
if request.method == 'POST':
form = AuthenticationForm(data=request.POST)
if form.is_valid():
user = form.get_user()
login(request,user)
return redirect('accounts:login')
else:
form = AuthenticationForm()
return render(request,'accounts/login.html', {'form':form})
then i tried this
class LoginView(FormView):
form_class = AuthenticationForm
template_name = 'login.html'
def form_valid(self, form):
email = form.cleaned_data['email']
password = form.cleaned_data['password']
user = authenticate(email=email, password=password)
# Check here if the user is an admin
if user is not None and user.is_active:
login(self.request, user)
return HttpResponseRedirect(self.success_url)
else:
return self.form_invalid(form)
Obviously i expect the user to be logged in
i think the code in this post is badly formatted. mainly it's my fault as i'm new to this platform
I've developed almost the same setup that you're describing (I didn't remove the username field, just stopped using it). If you haven't already seen it, Django's documentation at https://docs.djangoproject.com/en/2.2/topics/auth/customizing/#substituting-a-custom-user-model is quite helpful.
There are a couple of important things that need to be set up correctly for this to work.
The USERNAME_FIELD on your model should be set to the name of your email field.
The AUTH_USER_MODEL needs to point to your custom user model.
class MyUser(AbstractUser):
USERNAME_FIELD = 'email'
AUTH_USER_MODEL = 'customauth.MyUser'
Since you've removed the username field altogether you might need to subclass django.contrib.auth.forms.AuthenticationForm and django.contrib.auth.views.LoginView to avoid breaking things, but Django should handle a different authentication field quite well.
If you do wind up needing to subclass the view, https://ccbv.co.uk/projects/Django/2.2/django.contrib.auth.views/LoginView/ is a great place to look over all the methods to see what's going on.
Edit - On Subclassing and it's necessity
What I was saying about possibly needing to subclass certain things was influenced by https://docs.djangoproject.com/en/2.2/topics/auth/customizing/#writing-a-manager-for-a-custom-user-model. I wasn't sure if there were other parts of the authentication system that would need you to customize them because you removed the username field.
I've read through some of the source code for Django's authentication system. Here's the path that's being followed.
When the POST request is made to Django's authentication view the authentication form is validated. https://github.com/django/django/blob/2.2.2/django/contrib/auth/forms.py#L191
The authenticate function is called. This iterates through the backends set up and tries to authenticate on each of them. https://github.com/django/django/blob/2.2.2/django/contrib/auth/__init__.py#L62
Django's built-in authentication backend gets the user if it exists using the natural key. https://github.com/django/django/blob/2.2.2/django/contrib/auth/backends.py#L16
We can see in the base manager that the natural key used is the field named by USERNAME_FIELD. https://github.com/django/django/blob/2.2.2/django/contrib/auth/base_user.py#L43
If the form is valid, meaning that the user is authenticated properly, the user is then logged in. https://github.com/django/django/blob/2.2.2/django/contrib/auth/views.py#L88
My reaction is that it looks like Django should work out of the box for your use case. You shouldn't need to write a backend. Here's the extent of the code my gut says you should have to write.
from django.contrib.auth import views as auth_views
from django.shortcuts import resolve_url
class LoginView(auth_views.LoginView):
template_name = 'accounts/login.html'
def get_success_url(self):
return resolve_url('accounts:login')
I don't know if this could be of any use to somebody but I can confirm that Django can authenticate you well with its own Login view if you just replace the username with an email field on your custom user model (as long as you specify the USERNAME_FIELD on the custom user model and are indeed using it by declaring it in the settings).
As I was expecting this behavior I designed a custom HTML form with email/password inputs and used the same principles I would use with the original user model authentication. It was failing though and I understood it was because I wasn't adapting my form to the original Login view expectations or would have worked from the start.
Just make sure to remember that the form HTML input tag for the email address needs to have "type" set to "email" but "id" set to "id_username" and "name" to "username".
This means you can just replace username with an email field and authenticate normally. I did not even declare a Login view for my login form to work, the Django view automacally used from the core is just being called at /accounts/login and working on its own. I'm working on Django 3.2

Is it possible to forge HttpRequest attributes for a Django server

I am writing a web app using Django. I am trying to allow a user to see its profile and only his own.
if(not request.user.id == request.GET.get('user_id', '')):
raise PermissionDenied
My question is: is it safe to check this way or is it possible for a smart kid to somehow alter the value in request.user.id to match the user_id of anyone?
The user must be logged in before accessing this page using this:
user = LDAPBackend().authenticate(username=username, password=password)
if(user is not None):
login(request, user)
Yes it should be safe.
request.user get's only populated when authentication with session cookies. Unless and until someone steals the cookie or token it should be no issue.
One thing i don't understand is why do you need user_id parameter here to be explicitly passed.
if you are putting logged in compulsory to view the page. there are two way i can see this.
/profile
Directly get user profile corresponding to the request.user
/<username>
Query the profile corresponding to the username and compare it with request.user.id
request.user is set using AuthenticationMiddleware for each request:
Adds the user attribute, representing the currently-logged-in user, to every incoming HttpRequest object.
If a user is not logged in then request.user is set to Anonymous User. Have a look at Authentication in Web requests.
So, I am not sure how would a smart kid alter the id of the logged-in user.
Mostly, there is a one-to-one relation between the user and its profile. If that's the case you can modify the queryset to get the profile for request.user directly.
request.user is already an object about the current user who send the request to get the page. You can use login_required or to only allow user login to access (2 solutions : decorator or Mixin).
And then you can use your condition to load the page in the function. Example:
=> url.py:
url(r'^profile/$', login_required(app.views.profile), name='profile'),
=> views.py :
def profile(request):
try:
myProfile = User.objects.get(username=request.user.username)
except ObjectDoesNotExist:
return render(request, "error.html", {'message' : 'No Profile Found'})
return render(request, "app/profile.html",
{'myProfile': myProfile})
Like this you can only display YOUR profile (user who send the request) AND you need to be logged.
EDIT: if you don't want "try and catch" you can use get_object_or_404(User, username=request.user.username)

How to make Django admin site accessed by non-staff user?

I would like to implement a 2nd admin site which provides a subset of feature of the primary admin site. That's possible and described in the Django docs
However, I would like to limit access on the primary admin site. Some users can access the 2ndary site but not the primary site.
In order to implement that feature, I would like these users not to be in the staff (is_staff=False) and rewrite the AdminSite.has_permission
class SecondaryAdminSite(AdminSite):
def has_permission(self, request):
if request.user.is_anonymous:
try:
username = request.POST['username']
password = request.POST['password']
except KeyError:
return False
try:
user = User.objects.get(username = username)
if user.check_password(password):
return user.has_perm('app.change_onlythistable')
else:
return False
except User.DoesNotExist:
return False
else:
return request.user.has_perm('app.change_onlythistable')
Unfortunately, this approach doesn't work. The user can login but can't see anything in the secondary admin site.
What's wrong with this approach?
Any idea how to implement this feature?
Thanks in advance
Here's what worked for me with Django >= 3.2.
Create a subclass of AdminSite
Override the has_permission() method to remove the is_staff check.
Override the login_form to use AuthenticationForm.
AdminSite uses AdminAuthenticationForm, which extends AuthenticationForm and adds a check for is_staff.
Code
# PROJECT/APP/admin.py
from django.contrib.admin import AdminSite
from django.contrib.admin.forms import AuthenticationForm
class MyAdminSite(AdminSite):
"""
App-specific admin site implementation
"""
login_form = AuthenticationForm
site_header = 'Todomon'
def has_permission(self, request):
"""
Checks if the current user has access.
"""
return request.user.is_active
site = MyAdminSite(name='myadmin')
I think that your approach should now be possible: http://code.djangoproject.com/ticket/14434 (closed 5 weeks ago)
However, the explicit "is_staff" check is still done in two places (apart from the staff_member_required decorator):
django.contrib.admin.forms.AdminAuthenticationForm.clean()
On top of "has_permission()" you'd need to provide your non-staff AdminSite with a "login_form" that doesn't do the is_staff check, so could just subclass and adjust clean() accordingly.
templates/admin/base.html
would need to be slightly customized.
The div with id "user-tools" is only shown for active staff members. I'm assuming that's done because the login form also uses this template, and someone could be logged in as an active non-staff member but still should'nt see those links.
What's wrong with this approach? Any idea how to implement this feature?
What's wrong with this approach is that permissions and groups can already provide you with what you need. There is no need to subclass AdminSite if all you need is to divide users.
This is probably why this feature is so poorly documented, IMHO

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