Using the Django authentication system¶
This document explains the usage of Django’s authentication system in its default configuration. This configuration has evolved to serve the most common project needs, handling a reasonably wide range of tasks, and has a careful implementation of passwords and permissions. For projects where authentication needs differ from the default, Django supports extensive extension and customization of authentication.
Django authentication provides both authentication and authorization together and is generally referred to as the authentication system, as these features are somewhat coupled.
User objects¶
User objects are the core of the
authentication system. They typically represent the people interacting with
your site and are used to enable things like restricting access, registering
user profiles, associating content with creators etc. Only one class of user
exists in Django’s authentication framework, i.e., 'superusers' or admin 'staff' users are just user objects with
special attributes set, not different classes of user objects.
The primary attributes of the default user are:
See the full API documentation for
full reference, the documentation that follows is more task oriented.
Creating users¶
The most direct way to create users is to use the included
create_user() helper function:
>>> from django.contrib.auth.models import User
>>> user = User.objects.create_user('john', 'lennon@thebeatles.com', 'johnpassword')
# At this point, user is a User object that has already been saved
# to the database. You can continue to change its attributes
# if you want to change other fields.
>>> user.last_name = 'Lennon'
>>> user.save()
If you have the Django admin installed, you can also create users interactively.
Creating superusers¶
Create superusers using the createsuperuser command:
$ python manage.py createsuperuser --username=joe --email=joe@example.com
You will be prompted for a password. After you enter one, the user will be
created immediately. If you leave off the --username or --email options, it will
prompt you for those values.
Changing passwords¶
Django does not store raw (clear text) passwords on the user model, but only a hash (see documentation of how passwords are managed for full details). Because of this, do not attempt to manipulate the password attribute of the user directly. This is why a helper function is used when creating a user.
To change a user’s password, you have several options:
manage.py changepassword *username* offers a method
of changing a user’s password from the command line. It prompts you to
change the password of a given user which you must enter twice. If
they both match, the new password will be changed immediately. If you
do not supply a user, the command will attempt to change the password
whose username matches the current system user.
You can also change a password programmatically, using
set_password():
>>> from django.contrib.auth.models import User
>>> u = User.objects.get(username='john')
>>> u.set_password('new password')
>>> u.save()
If you have the Django admin installed, you can also change user’s passwords on the authentication system’s admin pages.
Django also provides views and forms that may be used to allow users to change their own passwords.
Changing a user’s password will log out all their sessions. See Session invalidation on password change for details.
Authenticating users¶
- 
authenticate(request=None, **credentials)¶
- Use - authenticate()to verify a set of credentials. It takes credentials as keyword arguments,- usernameand- passwordfor the default case, checks them against each authentication backend, and returns a- Userobject if the credentials are valid for a backend. If the credentials aren’t valid for any backend or if a backend raises- PermissionDenied, it returns- None. For example:- from django.contrib.auth import authenticate user = authenticate(username='john', password='secret') if user is not None: # A backend authenticated the credentials else: # No backend authenticated the credentials - requestis an optional- HttpRequestwhich is passed on the- authenticate()method of the authentication backends.- Note - This is a low level way to authenticate a set of credentials; for example, it’s used by the - RemoteUserMiddleware. Unless you are writing your own authentication system, you probably won’t use this. Rather if you’re looking for a way to login a user, use the- LoginView.
Permissions and Authorization¶
Django comes with a built-in permissions system. It provides a way to assign permissions to specific users and groups of users.
It’s used by the Django admin site, but you’re welcome to use it in your own code.
The Django admin site uses permissions as follows:
- Access to view objects is limited to users with the “view” or “change” permission for that type of object.
- Access to view the “add” form and add an object is limited to users with the “add” permission for that type of object.
- Access to view the change list, view the “change” form and change an object is limited to users with the “change” permission for that type of object.
- Access to delete an object is limited to users with the “delete” permission for that type of object.
Permissions can be set not only per type of object, but also per specific
object instance. By using the
has_view_permission(),
has_add_permission(),
has_change_permission() and
has_delete_permission() methods provided
by the ModelAdmin class, it is possible to
customize permissions for different object instances of the same type.
User objects have two many-to-many
fields: groups and user_permissions.
User objects can access their related
objects in the same way as any other Django model:
myuser.groups.set([group_list])
myuser.groups.add(group, group, ...)
myuser.groups.remove(group, group, ...)
myuser.groups.clear()
myuser.user_permissions.set([permission_list])
myuser.user_permissions.add(permission, permission, ...)
myuser.user_permissions.remove(permission, permission, ...)
myuser.user_permissions.clear()
Default permissions¶
When django.contrib.auth is listed in your INSTALLED_APPS
setting, it will ensure that four default permissions – add, change, delete,
and view – are created for each Django model defined in one of your installed
applications.
These permissions will be created when you run manage.py migrate; the first time you run migrate after adding
django.contrib.auth to INSTALLED_APPS, the default permissions
will be created for all previously-installed models, as well as for any new
models being installed at that time. Afterward, it will create default
permissions for new models each time you run manage.py migrate (the function that creates permissions is connected to the
post_migrate signal).
Assuming you have an application with an
app_label foo and a model named Bar,
to test for basic permissions you should use:
- add: user.has_perm('foo.add_bar')
- change: user.has_perm('foo.change_bar')
- delete: user.has_perm('foo.delete_bar')
- view: user.has_perm('foo.view_bar')
The Permission model is rarely accessed
directly.
Groups¶
django.contrib.auth.models.Group models are a generic way of
categorizing users so you can apply permissions, or some other label, to those
users. A user can belong to any number of groups.
A user in a group automatically has the permissions granted to that group. For
example, if the group Site editors has the permission
can_edit_home_page, any user in that group will have that permission.
Beyond permissions, groups are a convenient way to categorize users to give
them some label, or extended functionality. For example, you could create a
group 'Special users', and you could write code that could, say, give them
access to a members-only portion of your site, or send them members-only email
messages.
Programmatically creating permissions¶
While custom permissions can be defined within
a model’s Meta class, you can also create permissions directly. For
example, you can create the can_publish permission for a BlogPost model
in myapp:
from myapp.models import BlogPost
from django.contrib.auth.models import Permission
from django.contrib.contenttypes.models import ContentType
content_type = ContentType.objects.get_for_model(BlogPost)
permission = Permission.objects.create(
    codename='can_publish',
    name='Can Publish Posts',
    content_type=content_type,
)
The permission can then be assigned to a
User via its user_permissions
attribute or to a Group via its
permissions attribute.
Proxy models need their own content type
If you want to create permissions for a proxy model, pass for_concrete_model=False to
ContentTypeManager.get_for_model() to get the appropriate
ContentType:
content_type = ContentType.objects.get_for_model(BlogPostProxy, for_concrete_model=False)
In older versions, proxy models use the content type of the concrete model.
Permission caching¶
The ModelBackend caches permissions on
the user object after the first time they need to be fetched for a permissions
check. This is typically fine for the request-response cycle since permissions
aren’t typically checked immediately after they are added (in the admin, for
example). If you are adding permissions and checking them immediately
afterward, in a test or view for example, the easiest solution is to re-fetch
the user from the database. For example:
from django.contrib.auth.models import Permission, User
from django.contrib.contenttypes.models import ContentType
from django.shortcuts import get_object_or_404
from myapp.models import BlogPost
def user_gains_perms(request, user_id):
    user = get_object_or_404(User, pk=user_id)
    # any permission check will cache the current set of permissions
    user.has_perm('myapp.change_blogpost')
    content_type = ContentType.objects.get_for_model(BlogPost)
    permission = Permission.objects.get(
        codename='change_blogpost',
        content_type=content_type,
    )
    user.user_permissions.add(permission)
    # Checking the cached permission set
    user.has_perm('myapp.change_blogpost')  # False
    # Request new instance of User
    # Be aware that user.refresh_from_db() won't clear the cache.
    user = get_object_or_404(User, pk=user_id)
    # Permission cache is repopulated from the database
    user.has_perm('myapp.change_blogpost')  # True
    ...
Proxy models¶
Proxy models work exactly the same way as concrete models. Permissions are created using the own content type of the proxy model. Proxy models don’t inherit the permissions of the concrete model they subclass:
class Person(models.Model):
    class Meta:
        permissions = [('can_eat_pizzas', 'Can eat pizzas')]
class Student(Person):
    class Meta:
        proxy = True
        permissions = [('can_deliver_pizzas', 'Can deliver pizzas')]
>>> # Fetch the content type for the proxy model.
>>> content_type = ContentType.objects.get_for_model(Student, for_concrete_model=False)
>>> student_permissions = Permission.objects.filter(content_type=content_type)
>>> [p.codename for p in student_permissions]
['add_student', 'change_student', 'delete_student', 'view_student',
'can_deliver_pizzas']
>>> for permission in student_permissions:
...     user.user_permissions.add(permission)
>>> user.has_perm('app.add_person')
False
>>> user.has_perm('app.can_eat_pizzas')
False
>>> user.has_perms(('app.add_student', 'app.can_deliver_pizzas'))
True
In older versions, permissions for proxy models use the content type of the concrete model rather than content type of the proxy model.
Authentication in Web requests¶
Django uses sessions and middleware to hook the
authentication system into request objects.
These provide a request.user  attribute
on every request which represents the current user. If the current user has not
logged in, this attribute will be set to an instance
of AnonymousUser, otherwise it will be an
instance of User.
You can tell them apart with
is_authenticated, like so:
if request.user.is_authenticated:
    # Do something for authenticated users.
    ...
else:
    # Do something for anonymous users.
    ...
How to log a user in¶
If you have an authenticated user you want to attach to the current session
- this is done with a login() function.
- 
login(request, user, backend=None)¶
- To log a user in, from a view, use - login(). It takes an- HttpRequestobject and a- Userobject.- login()saves the user’s ID in the session, using Django’s session framework.- Note that any data set during the anonymous session is retained in the session after a user logs in. - This example shows how you might use both - authenticate()and- login():- from django.contrib.auth import authenticate, login def my_view(request): username = request.POST['username'] password = request.POST['password'] user = authenticate(request, username=username, password=password) if user is not None: login(request, user) # Redirect to a success page. ... else: # Return an 'invalid login' error message. ... 
Selecting the authentication backend¶
When a user logs in, the user’s ID and the backend that was used for authentication are saved in the user’s session. This allows the same authentication backend to fetch the user’s details on a future request. The authentication backend to save in the session is selected as follows:
- Use the value of the optional backendargument, if provided.
- Use the value of the user.backendattribute, if present. This allows pairingauthenticate()andlogin():authenticate()sets theuser.backendattribute on the user object it returns.
- Use the backendinAUTHENTICATION_BACKENDS, if there is only one.
- Otherwise, raise an exception.
In cases 1 and 2, the value of the backend argument or the user.backend
attribute should be a dotted import path string (like that found in
AUTHENTICATION_BACKENDS), not the actual backend class.
How to log a user out¶
- 
logout(request)¶
- To log out a user who has been logged in via - django.contrib.auth.login(), use- django.contrib.auth.logout()within your view. It takes an- HttpRequestobject and has no return value. Example:- from django.contrib.auth import logout def logout_view(request): logout(request) # Redirect to a success page. - Note that - logout()doesn’t throw any errors if the user wasn’t logged in.- When you call - logout(), the session data for the current request is completely cleaned out. All existing data is removed. This is to prevent another person from using the same Web browser to log in and have access to the previous user’s session data. If you want to put anything into the session that will be available to the user immediately after logging out, do that after calling- django.contrib.auth.logout().
Limiting access to logged-in users¶
The raw way¶
The raw way to limit access to pages is to check
request.user.is_authenticated and either redirect to a
login page:
from django.conf import settings
from django.shortcuts import redirect
def my_view(request):
    if not request.user.is_authenticated:
        return redirect('%s?next=%s' % (settings.LOGIN_URL, request.path))
    # ...
…or display an error message:
from django.shortcuts import render
def my_view(request):
    if not request.user.is_authenticated:
        return render(request, 'myapp/login_error.html')
    # ...
The login_required decorator¶
- 
login_required(redirect_field_name='next', login_url=None)¶
- As a shortcut, you can use the convenient - login_required()decorator:- from django.contrib.auth.decorators import login_required @login_required def my_view(request): ... - login_required()does the following:- If the user isn’t logged in, redirect to
settings.LOGIN_URL, passing the current absolute path in the query string. Example:/accounts/login/?next=/polls/3/.
- If the user is logged in, execute the view normally. The view code is free to assume the user is logged in.
 - By default, the path that the user should be redirected to upon successful authentication is stored in a query string parameter called - "next". If you would prefer to use a different name for this parameter,- login_required()takes an optional- redirect_field_nameparameter:- from django.contrib.auth.decorators import login_required @login_required(redirect_field_name='my_redirect_field') def my_view(request): ... - Note that if you provide a value to - redirect_field_name, you will most likely need to customize your login template as well, since the template context variable which stores the redirect path will use the value of- redirect_field_nameas its key rather than- "next"(the default).- login_required()also takes an optional- login_urlparameter. Example:- from django.contrib.auth.decorators import login_required @login_required(login_url='/accounts/login/') def my_view(request): ... - Note that if you don’t specify the - login_urlparameter, you’ll need to ensure that the- settings.LOGIN_URLand your login view are properly associated. For example, using the defaults, add the following lines to your URLconf:- from django.contrib.auth import views as auth_views path('accounts/login/', auth_views.LoginView.as_view()), - The - settings.LOGIN_URLalso accepts view function names and named URL patterns. This allows you to freely remap your login view within your URLconf without having to update the setting.
- If the user isn’t logged in, redirect to
Note
The login_required decorator does NOT check the is_active flag on a
user, but the default AUTHENTICATION_BACKENDS reject inactive
users.
See also
If you are writing custom views for Django’s admin (or need the same
authorization check that the built-in views use), you may find the
django.contrib.admin.views.decorators.staff_member_required()
decorator a useful alternative to login_required().
The LoginRequired mixin¶
When using class-based views, you can
achieve the same behavior as with login_required by using the
LoginRequiredMixin. This mixin should be at the leftmost position in the
inheritance list.
- 
class LoginRequiredMixin¶
- If a view is using this mixin, all requests by non-authenticated users will be redirected to the login page or shown an HTTP 403 Forbidden error, depending on the - raise_exceptionparameter.- You can set any of the parameters of - AccessMixinto customize the handling of unauthorized users:- from django.contrib.auth.mixins import LoginRequiredMixin class MyView(LoginRequiredMixin, View): login_url = '/login/' redirect_field_name = 'redirect_to' 
Note
Just as the login_required decorator, this mixin does NOT check the
is_active flag on a user, but the default
AUTHENTICATION_BACKENDS reject inactive users.
Limiting access to logged-in users that pass a test¶
To limit access based on certain permissions or some other test, you’d do essentially the same thing as described in the previous section.
You can run your test on request.user in
the view directly. For example, this view checks to make sure the user has an
email in the desired domain and if not, redirects to the login page:
from django.shortcuts import redirect
def my_view(request):
    if not request.user.email.endswith('@example.com'):
        return redirect('/login/?next=%s' % request.path)
    # ...
- 
user_passes_test(test_func, login_url=None, redirect_field_name='next')¶
- As a shortcut, you can use the convenient - user_passes_testdecorator which performs a redirect when the callable returns- False:- from django.contrib.auth.decorators import user_passes_test def email_check(user): return user.email.endswith('@example.com') @user_passes_test(email_check) def my_view(request): ... - user_passes_test()takes a required argument: a callable that takes a- Userobject and returns- Trueif the user is allowed to view the page. Note that- user_passes_test()does not automatically check that the- Useris not anonymous.- user_passes_test()takes two optional arguments:- login_url
- Lets you specify the URL that users who don’t pass the test will be
redirected to. It may be a login page and defaults to
settings.LOGIN_URLif you don’t specify one.
- redirect_field_name
- Same as for login_required(). Setting it toNoneremoves it from the URL, which you may want to do if you are redirecting users that don’t pass the test to a non-login page where there’s no “next page”.
 - For example: - @user_passes_test(email_check, login_url='/login/') def my_view(request): ... 
- 
class UserPassesTestMixin¶
- When using class-based views, you can use the - UserPassesTestMixinto do this.- 
test_func()¶
- You have to override the - test_func()method of the class to provide the test that is performed. Furthermore, you can set any of the parameters of- AccessMixinto customize the handling of unauthorized users:- from django.contrib.auth.mixins import UserPassesTestMixin class MyView(UserPassesTestMixin, View): def test_func(self): return self.request.user.email.endswith('@example.com') 
 - 
get_test_func()¶
- You can also override the - get_test_func()method to have the mixin use a differently named function for its checks (instead of- test_func()).
 - Stacking - UserPassesTestMixin- Due to the way - UserPassesTestMixinis implemented, you cannot stack them in your inheritance list. The following does NOT work:- class TestMixin1(UserPassesTestMixin): def test_func(self): return self.request.user.email.endswith('@example.com') class TestMixin2(UserPassesTestMixin): def test_func(self): return self.request.user.username.startswith('django') class MyView(TestMixin1, TestMixin2, View): ... - If - TestMixin1would call- super()and take that result into account,- TestMixin1wouldn’t work standalone anymore.
- 
The permission_required decorator¶
- 
permission_required(perm, login_url=None, raise_exception=False)¶
- It’s a relatively common task to check whether a user has a particular permission. For that reason, Django provides a shortcut for that case: the - permission_required()decorator.:- from django.contrib.auth.decorators import permission_required @permission_required('polls.add_choice') def my_view(request): ... - Just like the - has_perm()method, permission names take the form- "<app label>.<permission codename>"(i.e.- polls.add_choicefor a permission on a model in the- pollsapplication).- The decorator may also take an iterable of permissions, in which case the user must have all of the permissions in order to access the view. - Note that - permission_required()also takes an optional- login_urlparameter:- from django.contrib.auth.decorators import permission_required @permission_required('polls.add_choice', login_url='/loginpage/') def my_view(request): ... - As in the - login_required()decorator,- login_urldefaults to- settings.LOGIN_URL.- If the - raise_exceptionparameter is given, the decorator will raise- PermissionDenied, prompting the 403 (HTTP Forbidden) view instead of redirecting to the login page.- If you want to use - raise_exceptionbut also give your users a chance to login first, you can add the- login_required()decorator:- from django.contrib.auth.decorators import login_required, permission_required @login_required @permission_required('polls.add_choice', raise_exception=True) def my_view(request): ... - This also avoids a redirect loop when - LoginView’s- redirect_authenticated_user=Trueand the logged-in user doesn’t have all of the required permissions.
The PermissionRequiredMixin mixin¶
To apply permission checks to class-based views, you can use the PermissionRequiredMixin:
- 
class PermissionRequiredMixin¶
- This mixin, just like the - permission_requireddecorator, checks whether the user accessing a view has all given permissions. You should specify the permission (or an iterable of permissions) using the- permission_requiredparameter:- from django.contrib.auth.mixins import PermissionRequiredMixin class MyView(PermissionRequiredMixin, View): permission_required = 'polls.add_choice' # Or multiple of permissions: permission_required = ('polls.view_choice', 'polls.change_choice') - You can set any of the parameters of - AccessMixinto customize the handling of unauthorized users.- You may also override these methods: - 
get_permission_required()¶
- Returns an iterable of permission names used by the mixin. Defaults to the - permission_requiredattribute, converted to a tuple if necessary.
 - 
has_permission()¶
- Returns a boolean denoting whether the current user has permission to execute the decorated view. By default, this returns the result of calling - has_perms()with the list of permissions returned by- get_permission_required().
 
- 
Redirecting unauthorized requests in class-based views¶
To ease the handling of access restrictions in class-based views, the AccessMixin can be used to configure
the behavior of a view when access is denied. Authenticated users are denied
access with an HTTP 403 Forbidden response. Anonymous users are redirected to
the login page or shown an HTTP 403 Forbidden response, depending on the
raise_exception attribute.
- 
class AccessMixin¶
- 
login_url¶
- Default return value for - get_login_url(). Defaults to- Nonein which case- get_login_url()falls back to- settings.LOGIN_URL.
 - 
permission_denied_message¶
- Default return value for - get_permission_denied_message(). Defaults to an empty string.
 - 
redirect_field_name¶
- Default return value for - get_redirect_field_name(). Defaults to- "next".
 - 
raise_exception¶
- If this attribute is set to - True, a- PermissionDeniedexception is raised when the conditions are not met. When- False(the default), anonymous users are redirected to the login page.
 - 
get_login_url()¶
- Returns the URL that users who don’t pass the test will be redirected to. Returns - login_urlif set, or- settings.LOGIN_URLotherwise.
 - 
get_permission_denied_message()¶
- When - raise_exceptionis- True, this method can be used to control the error message passed to the error handler for display to the user. Returns the- permission_denied_messageattribute by default.
 - 
get_redirect_field_name()¶
- Returns the name of the query parameter that will contain the URL the user should be redirected to after a successful login. If you set this to - None, a query parameter won’t be added. Returns the- redirect_field_nameattribute by default.
 - 
handle_no_permission()¶
- Depending on the value of - raise_exception, the method either raises a- PermissionDeniedexception or redirects the user to the- login_url, optionally including the- redirect_field_nameif it is set.
 
- 
Session invalidation on password change¶
If your AUTH_USER_MODEL inherits from
AbstractBaseUser or implements its own
get_session_auth_hash()
method, authenticated sessions will include the hash returned by this function.
In the AbstractBaseUser case, this is an
HMAC of the password field. Django verifies that the hash in the session for
each request matches the one that’s computed during the request. This allows a
user to log out all of their sessions by changing their password.
The default password change views included with Django,
PasswordChangeView and the
user_change_password view in the django.contrib.auth admin, update
the session with the new password hash so that a user changing their own
password won’t log themselves out. If you have a custom password change view
and wish to have similar behavior, use the update_session_auth_hash()
function.
- 
update_session_auth_hash(request, user)¶
- This function takes the current request and the updated user object from which the new session hash will be derived and updates the session hash appropriately. It also rotates the session key so that a stolen session cookie will be invalidated. - Example usage: - from django.contrib.auth import update_session_auth_hash def password_change(request): if request.method == 'POST': form = PasswordChangeForm(user=request.user, data=request.POST) if form.is_valid(): form.save() update_session_auth_hash(request, form.user) else: ... 
Note
Since
get_session_auth_hash()
is based on SECRET_KEY, updating your site to use a new secret
will invalidate all existing sessions.
Authentication Views¶
Django provides several views that you can use for handling login, logout, and password management. These make use of the stock auth forms but you can pass in your own forms as well.
Django provides no default template for the authentication views. You should create your own templates for the views you want to use. The template context is documented in each view, see All authentication views.
Using the views¶
There are different methods to implement these views in your project. The
easiest way is to include the provided URLconf in django.contrib.auth.urls
in your own URLconf, for example:
urlpatterns = [
    path('accounts/', include('django.contrib.auth.urls')),
]
This will include the following URL patterns:
accounts/login/ [name='login']
accounts/logout/ [name='logout']
accounts/password_change/ [name='password_change']
accounts/password_change/done/ [name='password_change_done']
accounts/password_reset/ [name='password_reset']
accounts/password_reset/done/ [name='password_reset_done']
accounts/reset/<uidb64>/<token>/ [name='password_reset_confirm']
accounts/reset/done/ [name='password_reset_complete']
The views provide a URL name for easier reference. See the URL documentation for details on using named URL patterns.
If you want more control over your URLs, you can reference a specific view in your URLconf:
from django.contrib.auth import views as auth_views
urlpatterns = [
    path('change-password/', auth_views.PasswordChangeView.as_view()),
]
The views have optional arguments you can use to alter the behavior of the
view. For example, if you want to change the template name a view uses, you can
provide the template_name argument. A way to do this is to provide keyword
arguments in the URLconf, these will be passed on to the view. For example:
urlpatterns = [
    path(
        'change-password/',
        auth_views.PasswordChangeView.as_view(template_name='change-password.html'),
    ),
]
All views are class-based, which allows you to easily customize them by subclassing.
All authentication views¶
This is a list with all the views django.contrib.auth provides. For
implementation details see Using the views.
- 
class LoginView¶
- URL name: - login- See the URL documentation for details on using named URL patterns. - Attributes: - template_name: The name of a template to display for the view used to log the user in. Defaults to- registration/login.html.
- redirect_field_name: The name of a- GETfield containing the URL to redirect to after login. Defaults to- next.
- authentication_form: A callable (typically a form class) to use for authentication. Defaults to- AuthenticationForm.
- extra_context: A dictionary of context data that will be added to the default context data passed to the template.
- redirect_authenticated_user: A boolean that controls whether or not authenticated users accessing the login page will be redirected as if they had just successfully logged in. Defaults to- False.- Warning - If you enable - redirect_authenticated_user, other websites will be able to determine if their visitors are authenticated on your site by requesting redirect URLs to image files on your website. To avoid this “social media fingerprinting” information leakage, host all images and your favicon on a separate domain.- Enabling - redirect_authenticated_usercan also result in a redirect loop when using the- permission_required()decorator unless the- raise_exceptionparameter is used.
- success_url_allowed_hosts: A- setof hosts, in addition to- request.get_host(), that are safe for redirecting after login. Defaults to an empty- set.
 - Here’s what - LoginViewdoes:- If called via GET, it displays a login form that POSTs to the same URL. More on this in a bit.
- If called via POSTwith user submitted credentials, it tries to log the user in. If login is successful, the view redirects to the URL specified innext. Ifnextisn’t provided, it redirects tosettings.LOGIN_REDIRECT_URL(which defaults to/accounts/profile/). If login isn’t successful, it redisplays the login form.
 - It’s your responsibility to provide the html for the login template , called - registration/login.htmlby default. This template gets passed four template context variables:- form: A- Formobject representing the- AuthenticationForm.
- next: The URL to redirect to after successful login. This may contain a query string, too.
- site: The current- Site, according to the- SITE_IDsetting. If you don’t have the site framework installed, this will be set to an instance of- RequestSite, which derives the site name and domain from the current- HttpRequest.
- site_name: An alias for- site.name. If you don’t have the site framework installed, this will be set to the value of- request.META['SERVER_NAME']. For more on sites, see The “sites” framework.
 - If you’d prefer not to call the template - registration/login.html, you can pass the- template_nameparameter via the extra arguments to the- as_viewmethod in your URLconf. For example, this URLconf line would use- myapp/login.htmlinstead:- path('accounts/login/', auth_views.LoginView.as_view(template_name='myapp/login.html')), - You can also specify the name of the - GETfield which contains the URL to redirect to after login using- redirect_field_name. By default, the field is called- next.- Here’s a sample - registration/login.htmltemplate you can use as a starting point. It assumes you have a- base.htmltemplate that defines a- contentblock:- {% extends "base.html" %} {% block content %} {% if form.errors %} <p>Your username and password didn't match. Please try again.</p> {% endif %} {% if next %} {% if user.is_authenticated %} <p>Your account doesn't have access to this page. To proceed, please login with an account that has access.</p> {% else %} <p>Please login to see this page.</p> {% endif %} {% endif %} <form method="post" action="{% url 'login' %}"> {% csrf_token %} <table> <tr> <td>{{ form.username.label_tag }}</td> <td>{{ form.username }}</td> </tr> <tr> <td>{{ form.password.label_tag }}</td> <td>{{ form.password }}</td> </tr> </table> <input type="submit" value="login"> <input type="hidden" name="next" value="{{ next }}"> </form> {# Assumes you setup the password_reset view in your URLconf #} <p><a href="{% url 'password_reset' %}">Lost password?</a></p> {% endblock %} - If you have customized authentication (see Customizing Authentication) you can use a custom authentication form by setting the - authentication_formattribute. This form must accept a- requestkeyword argument in its- __init__()method and provide a- get_user()method which returns the authenticated user object (this method is only ever called after successful form validation).
- 
class LogoutView¶
- Logs a user out. - URL name: - logout- Attributes: - next_page: The URL to redirect to after logout. Defaults to- settings.LOGOUT_REDIRECT_URL.
- template_name: The full name of a template to display after logging the user out. Defaults to- registration/logged_out.html.
- redirect_field_name: The name of a- GETfield containing the URL to redirect to after log out. Defaults to- next. Overrides the- next_pageURL if the given- GETparameter is passed.
- extra_context: A dictionary of context data that will be added to the default context data passed to the template.
- success_url_allowed_hosts: A- setof hosts, in addition to- request.get_host(), that are safe for redirecting after logout. Defaults to an empty- set.
 - Template context: - title: The string “Logged out”, localized.
- site: The current- Site, according to the- SITE_IDsetting. If you don’t have the site framework installed, this will be set to an instance of- RequestSite, which derives the site name and domain from the current- HttpRequest.
- site_name: An alias for- site.name. If you don’t have the site framework installed, this will be set to the value of- request.META['SERVER_NAME']. For more on sites, see The “sites” framework.
 
- 
logout_then_login(request, login_url=None)¶
- Logs a user out, then redirects to the login page. - URL name: No default URL provided - Optional arguments: - login_url: The URL of the login page to redirect to. Defaults to- settings.LOGIN_URLif not supplied.
 
- 
class PasswordChangeView¶
- URL name: - password_change- Allows a user to change their password. - Attributes: - template_name: The full name of a template to use for displaying the password change form. Defaults to- registration/password_change_form.htmlif not supplied.
- success_url: The URL to redirect to after a successful password change. Defaults to- 'password_change_done'.
- form_class: A custom “change password” form which must accept a- userkeyword argument. The form is responsible for actually changing the user’s password. Defaults to- PasswordChangeForm.
- extra_context: A dictionary of context data that will be added to the default context data passed to the template.
 - Template context: - form: The password change form (see- form_classabove).
 
- 
class PasswordChangeDoneView¶
- URL name: - password_change_done- The page shown after a user has changed their password. - Attributes: - template_name: The full name of a template to use. Defaults to- registration/password_change_done.htmlif not supplied.
- extra_context: A dictionary of context data that will be added to the default context data passed to the template.
 
- 
class PasswordResetView¶
- URL name: - password_reset- Allows a user to reset their password by generating a one-time use link that can be used to reset the password, and sending that link to the user’s registered email address. - If the email address provided does not exist in the system, this view won’t send an email, but the user won’t receive any error message either. This prevents information leaking to potential attackers. If you want to provide an error message in this case, you can subclass - PasswordResetFormand use the- form_classattribute.- Note - Be aware that sending an email costs extra time, hence you may be vulnerable to an email address enumeration timing attack due to a difference between the duration of a reset request for an existing email address and the duration of a reset request for a nonexistent email address. To reduce the overhead, you can use a 3rd party package that allows to send emails asynchronously, e.g. django-mailer. - Users flagged with an unusable password (see - set_unusable_password()aren’t allowed to request a password reset to prevent misuse when using an external authentication source like LDAP. Note that they won’t receive any error message since this would expose their account’s existence but no mail will be sent either.- Attributes: - template_name: The full name of a template to use for displaying the password reset form. Defaults to- registration/password_reset_form.htmlif not supplied.
- form_class: Form that will be used to get the email of the user to reset the password for. Defaults to- PasswordResetForm.
- email_template_name: The full name of a template to use for generating the email with the reset password link. Defaults to- registration/password_reset_email.htmlif not supplied.
- subject_template_name: The full name of a template to use for the subject of the email with the reset password link. Defaults to- registration/password_reset_subject.txtif not supplied.
- token_generator: Instance of the class to check the one time link. This will default to- default_token_generator, it’s an instance of- django.contrib.auth.tokens.PasswordResetTokenGenerator.
- success_url: The URL to redirect to after a successful password reset request. Defaults to- 'password_reset_done'.
- from_email: A valid email address. By default Django uses the- DEFAULT_FROM_EMAIL.
- extra_context: A dictionary of context data that will be added to the default context data passed to the template.
- html_email_template_name: The full name of a template to use for generating a- text/htmlmultipart email with the password reset link. By default, HTML email is not sent.
- extra_email_context: A dictionary of context data that will be available in the email template. It can be used to override default template context values listed below e.g.- domain.
 - Template context: - form: The form (see- form_classabove) for resetting the user’s password.
 - Email template context: - email: An alias for- user.email
- user: The current- User, according to the- emailform field. Only active users are able to reset their passwords (- User.is_active is True).
- site_name: An alias for- site.name. If you don’t have the site framework installed, this will be set to the value of- request.META['SERVER_NAME']. For more on sites, see The “sites” framework.
- domain: An alias for- site.domain. If you don’t have the site framework installed, this will be set to the value of- request.get_host().
- protocol: http or https
- uid: The user’s primary key encoded in base 64.
- token: Token to check that the reset link is valid.
 - Sample - registration/password_reset_email.html(email body template):- Someone asked for password reset for email {{ email }}. Follow the link below: {{ protocol}}://{{ domain }}{% url 'password_reset_confirm' uidb64=uid token=token %} - The same template context is used for subject template. Subject must be single line plain text string. 
- 
class PasswordResetDoneView¶
- URL name: - password_reset_done- The page shown after a user has been emailed a link to reset their password. This view is called by default if the - PasswordResetViewdoesn’t have an explicit- success_urlURL set.- Note - If the email address provided does not exist in the system, the user is inactive, or has an unusable password, the user will still be redirected to this view but no email will be sent. - Attributes: - template_name: The full name of a template to use. Defaults to- registration/password_reset_done.htmlif not supplied.
- extra_context: A dictionary of context data that will be added to the default context data passed to the template.
 
- 
class PasswordResetConfirmView¶
- URL name: - password_reset_confirm- Presents a form for entering a new password. - Keyword arguments from the URL: - uidb64: The user’s id encoded in base 64.
- token: Token to check that the password is valid.
 - Attributes: - template_name: The full name of a template to display the confirm password view. Default value is- registration/password_reset_confirm.html.
- token_generator: Instance of the class to check the password. This will default to- default_token_generator, it’s an instance of- django.contrib.auth.tokens.PasswordResetTokenGenerator.
- post_reset_login: A boolean indicating if the user should be automatically authenticated after a successful password reset. Defaults to- False.
- post_reset_login_backend: A dotted path to the authentication backend to use when authenticating a user if- post_reset_loginis- True. Required only if you have multiple- AUTHENTICATION_BACKENDSconfigured. Defaults to- None.
- form_class: Form that will be used to set the password. Defaults to- SetPasswordForm.
- success_url: URL to redirect after the password reset done. Defaults to- 'password_reset_complete'.
- extra_context: A dictionary of context data that will be added to the default context data passed to the template.
- reset_url_token: Token parameter displayed as a component of password reset URLs. Defaults to- 'set-password'.Changed in Django 3.0:- The - reset_url_tokenclass attribute was added.
 - Template context: - form: The form (see- form_classabove) for setting the new user’s password.
- validlink: Boolean, True if the link (combination of- uidb64and- token) is valid or unused yet.
 
- 
class PasswordResetCompleteView¶
- URL name: - password_reset_complete- Presents a view which informs the user that the password has been successfully changed. - Attributes: - template_name: The full name of a template to display the view. Defaults to- registration/password_reset_complete.html.
- extra_context: A dictionary of context data that will be added to the default context data passed to the template.
 
Helper functions¶
- 
redirect_to_login(next, login_url=None, redirect_field_name='next')¶
- Redirects to the login page, and then back to another URL after a successful login. - Required arguments: - next: The URL to redirect to after a successful login.
 - Optional arguments: - login_url: The URL of the login page to redirect to. Defaults to- settings.LOGIN_URLif not supplied.
- redirect_field_name: The name of a- GETfield containing the URL to redirect to after log out. Overrides- nextif the given- GETparameter is passed.
 
Built-in forms¶
If you don’t want to use the built-in views, but want the convenience of not
having to write forms for this functionality, the authentication system
provides several built-in forms located in django.contrib.auth.forms:
Note
The built-in authentication forms make certain assumptions about the user model that they are working with. If you’re using a custom user model, it may be necessary to define your own forms for the authentication system. For more information, refer to the documentation about using the built-in authentication forms with custom user models.
- 
class AdminPasswordChangeForm¶
- A form used in the admin interface to change a user’s password. - Takes the - useras the first positional argument.
- 
class AuthenticationForm¶
- A form for logging a user in. - Takes - requestas its first positional argument, which is stored on the form instance for use by sub-classes.- 
confirm_login_allowed(user)¶
- By default, - AuthenticationFormrejects users whose- is_activeflag is set to- False. You may override this behavior with a custom policy to determine which users can log in. Do this with a custom form that subclasses- AuthenticationFormand overrides the- confirm_login_allowed()method. This method should raise a- ValidationErrorif the given user may not log in.- For example, to allow all users to log in regardless of “active” status: - from django.contrib.auth.forms import AuthenticationForm class AuthenticationFormWithInactiveUsersOkay(AuthenticationForm): def confirm_login_allowed(self, user): pass - (In this case, you’ll also need to use an authentication backend that allows inactive users, such as - AllowAllUsersModelBackend.)- Or to allow only some active users to log in: - class PickyAuthenticationForm(AuthenticationForm): def confirm_login_allowed(self, user): if not user.is_active: raise forms.ValidationError( _("This account is inactive."), code='inactive', ) if user.username.startswith('b'): raise forms.ValidationError( _("Sorry, accounts starting with 'b' aren't welcome here."), code='no_b_users', ) 
 
- 
- 
class PasswordChangeForm¶
- A form for allowing a user to change their password. 
- 
class PasswordResetForm¶
- A form for generating and emailing a one-time use link to reset a user’s password. - 
send_mail(subject_template_name, email_template_name, context, from_email, to_email, html_email_template_name=None)¶
- Uses the arguments to send an - EmailMultiAlternatives. Can be overridden to customize how the email is sent to the user.- Parameters: - subject_template_name – the template for the subject.
- email_template_name – the template for the email body.
- context – context passed to the subject_template,email_template, andhtml_email_template(if it is notNone).
- from_email – the sender’s email.
- to_email – the email of the requester.
- html_email_template_name – the template for the HTML body;
defaults to None, in which case a plain text email is sent.
 - By default, - save()populates the- contextwith the same variables that- PasswordResetViewpasses to its email context.
 
- 
- 
class SetPasswordForm¶
- A form that lets a user change their password without entering the old password. 
- 
class UserChangeForm¶
- A form used in the admin interface to change a user’s information and permissions. 
- 
class UserCreationForm¶
- A - ModelFormfor creating a new user.- It has three fields: - username(from the user model),- password1, and- password2. It verifies that- password1and- password2match, validates the password using- validate_password(), and sets the user’s password using- set_password().
Authentication data in templates¶
The currently logged-in user and their permissions are made available in the
template context when you use
RequestContext.
Technicality
Technically, these variables are only made available in the template
context if you use RequestContext and the
'django.contrib.auth.context_processors.auth' context processor is
enabled. It is in the default generated settings file. For more, see the
RequestContext docs.
Users¶
When rendering a template RequestContext, the
currently logged-in user, either a  User
instance or an AnonymousUser instance, is
stored in the template variable {{ user }}:
{% if user.is_authenticated %}
    <p>Welcome, {{ user.username }}. Thanks for logging in.</p>
{% else %}
    <p>Welcome, new user. Please log in.</p>
{% endif %}
This template context variable is not available if a RequestContext is not
being used.
Permissions¶
The currently logged-in user’s permissions are stored in the template variable
{{ perms }}. This is an instance of
django.contrib.auth.context_processors.PermWrapper, which is a
template-friendly proxy of permissions.
Evaluating a single-attribute lookup of {{ perms }} as a boolean is a proxy
to User.has_module_perms(). For example, to check if
the logged-in user has any permissions in the foo app:
{% if perms.foo %}
Evaluating a two-level-attribute lookup as a boolean is a proxy to
User.has_perm(). For example,
to check if the logged-in user has the permission foo.add_vote:
{% if perms.foo.add_vote %}
Here’s a more complete example of checking permissions in a template:
{% if perms.foo %}
    <p>You have permission to do something in the foo app.</p>
    {% if perms.foo.add_vote %}
        <p>You can vote!</p>
    {% endif %}
    {% if perms.foo.add_driving %}
        <p>You can drive!</p>
    {% endif %}
{% else %}
    <p>You don't have permission to do anything in the foo app.</p>
{% endif %}
It is possible to also look permissions up by {% if in %} statements.
For example:
{% if 'foo' in perms %}
    {% if 'foo.add_vote' in perms %}
        <p>In lookup works, too.</p>
    {% endif %}
{% endif %}
Managing users in the admin¶
When you have both django.contrib.admin and django.contrib.auth
installed, the admin provides a convenient way to view and manage users,
groups, and permissions. Users can be created and deleted like any Django
model. Groups can be created, and permissions can be assigned to users or
groups. A log of user edits to models made within the admin is also stored and
displayed.
Creating users¶
You should see a link to “Users” in the “Auth” section of the main admin index page. The “Add user” admin page is different than standard admin pages in that it requires you to choose a username and password before allowing you to edit the rest of the user’s fields.
Also note: if you want a user account to be able to create users using the Django admin site, you’ll need to give them permission to add users and change users (i.e., the “Add user” and “Change user” permissions). If an account has permission to add users but not to change them, that account won’t be able to add users. Why? Because if you have permission to add users, you have the power to create superusers, which can then, in turn, change other users. So Django requires add and change permissions as a slight security measure.
Be thoughtful about how you allow users to manage permissions. If you give a non-superuser the ability to edit users, this is ultimately the same as giving them superuser status because they will be able to elevate permissions of users including themselves!
Changing passwords¶
User passwords are not displayed in the admin (nor stored in the database), but the password storage details are displayed. Included in the display of this information is a link to a password change form that allows admins to change user passwords.
 
          