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)[source]¶ Use
authenticate()
to verify a set of credentials. It takes credentials as keyword arguments,username
andpassword
for the default case, checks them against each authentication backend, and returns aUser
object if the credentials are valid for a backend. If the credentials aren’t valid for any backend or if a backend raisesPermissionDenied
, it returnsNone
. 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
request
is an optionalHttpRequest
which is passed on theauthenticate()
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 theLoginView
.
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)
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
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)[source]¶ To log a user in, from a view, use
login()
. It takes anHttpRequest
object and aUser
object.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()
andlogin()
: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
backend
argument, if provided. - Use the value of the
user.backend
attribute, if present. This allows pairingauthenticate()
andlogin()
:authenticate()
sets theuser.backend
attribute on the user object it returns. - Use the
backend
inAUTHENTICATION_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)[source]¶ To log out a user who has been logged in via
django.contrib.auth.login()
, usedjango.contrib.auth.logout()
within your view. It takes anHttpRequest
object 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 callingdjango.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(f'{settings.LOGIN_URL}?next={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)[source]¶ 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 optionalredirect_field_name
parameter: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 ofredirect_field_name
as its key rather than"next"
(the default).login_required()
also takes an optionallogin_url
parameter. 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_url
parameter, you’ll need to ensure that thesettings.LOGIN_URL
and 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_URL
also 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 LoginRequiredMixin
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_exception
parameter.You can set any of the parameters of
AccessMixin
to 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')[source]¶ As a shortcut, you can use the convenient
user_passes_test
decorator which performs a redirect when the callable returnsFalse
: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 aUser
object and returnsTrue
if the user is allowed to view the page. Note thatuser_passes_test()
does not automatically check that theUser
is 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_URL
if you don’t specify one. redirect_field_name
- Same as for
login_required()
. Setting it toNone
removes 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
UserPassesTestMixin
to 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 ofAccessMixin
to 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 oftest_func()
).
Stacking
UserPassesTestMixin
Due to the way
UserPassesTestMixin
is 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
TestMixin1
would callsuper()
and take that result into account,TestMixin1
wouldn’t work standalone anymore.-
The permission_required
decorator¶
-
permission_required
(perm, login_url=None, raise_exception=False)[source]¶ 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_choice
for a permission on a model in thepolls
application).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 optionallogin_url
parameter: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_url
defaults tosettings.LOGIN_URL
.If the
raise_exception
parameter is given, the decorator will raisePermissionDenied
, prompting the 403 (HTTP Forbidden) view instead of redirecting to the login page.If you want to use
raise_exception
but also give your users a chance to login first, you can add thelogin_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
’sredirect_authenticated_user=True
and 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_required
decorator, checks whether the user accessing a view has all given permissions. You should specify the permission (or an iterable of permissions) using thepermission_required
parameter: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
AccessMixin
to 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_required
attribute, 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 byget_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 toNone
in which caseget_login_url()
falls back tosettings.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
, aPermissionDenied
exception is raised when the conditions are not met. WhenFalse
(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_url
if set, orsettings.LOGIN_URL
otherwise.
-
get_permission_denied_message
()¶ When
raise_exception
isTrue
, this method can be used to control the error message passed to the error handler for display to the user. Returns thepermission_denied_message
attribute 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 theredirect_field_name
attribute by default.
-
handle_no_permission
()¶ Depending on the value of
raise_exception
, the method either raises aPermissionDenied
exception or redirects the user to thelogin_url
, optionally including theredirect_field_name
if 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)[source]¶ 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
, secret key values must be
rotated to avoid invalidating existing sessions when updating your site to
use a new secret. See SECRET_KEY_FALLBACKS
for details.
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.
Methods and Attributes
-
template_name
¶ The name of a template to display for the view used to log the user in. Defaults to
registration/login.html
.
-
next_page
¶ The URL to redirect to after login. Defaults to
LOGIN_REDIRECT_URL
.
-
redirect_field_name
¶ The name of a
GET
field containing the URL to redirect to after login. Defaults tonext
. Overrides theget_default_redirect_url()
URL if the givenGET
parameter is passed.
-
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_user
can also result in a redirect loop when using thepermission_required()
decorator unless theraise_exception
parameter is used.
-
success_url_allowed_hosts
¶ A
set
of hosts, in addition torequest.get_host()
, that are safe for redirecting after login. Defaults to an emptyset
.
-
get_default_redirect_url
()¶ Returns the URL to redirect to after login. The default implementation resolves and returns
next_page
if set, orLOGIN_REDIRECT_URL
otherwise.
Here’s what
LoginView
does:- If called via
GET
, it displays a login form that POSTs to the same URL. More on this in a bit. - If called via
POST
with user submitted credentials, it tries to log the user in. If login is successful, the view redirects to the URL specified innext
. Ifnext
isn’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.html
by default. This template gets passed four template context variables:form
: AForm
object representing theAuthenticationForm
.next
: The URL to redirect to after successful login. This may contain a query string, too.site
: The currentSite
, according to theSITE_ID
setting. If you don’t have the site framework installed, this will be set to an instance ofRequestSite
, which derives the site name and domain from the currentHttpRequest
.site_name
: An alias forsite.name
. If you don’t have the site framework installed, this will be set to the value ofrequest.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 thetemplate_name
parameter via the extra arguments to theas_view
method in your URLconf. For example, this URLconf line would usemyapp/login.html
instead:path('accounts/login/', auth_views.LoginView.as_view(template_name='myapp/login.html')),
You can also specify the name of the
GET
field which contains the URL to redirect to after login usingredirect_field_name
. By default, the field is callednext
.Here’s a sample
registration/login.html
template you can use as a starting point. It assumes you have abase.html
template that defines acontent
block:{% 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 set up 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_form
attribute. This form must accept arequest
keyword argument in its__init__()
method and provide aget_user()
method which returns the authenticated user object (this method is only ever called after successful form validation).-
-
class
LogoutView
¶ Logs a user out on
POST
requests.Deprecated since version 4.1: Support for logging out on
GET
requests is deprecated and will be removed in Django 5.0.URL name:
logout
Attributes:
-
next_page
¶ The URL to redirect to after logout. Defaults to
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
GET
field containing the URL to redirect to after log out. Defaults to'next'
. Overrides thenext_page
URL if the givenGET
parameter 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
set
of hosts, in addition torequest.get_host()
, that are safe for redirecting after logout. Defaults to an emptyset
.
Template context:
title
: The string “Logged out”, localized.site
: The currentSite
, according to theSITE_ID
setting. If you don’t have the site framework installed, this will be set to an instance ofRequestSite
, which derives the site name and domain from the currentHttpRequest
.site_name
: An alias forsite.name
. If you don’t have the site framework installed, this will be set to the value ofrequest.META['SERVER_NAME']
. For more on sites, see The “sites” framework.
-
-
logout_then_login
(request, login_url=None)¶ Logs a user out on
POST
requests, 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 tosettings.LOGIN_URL
if not supplied.
Deprecated since version 4.1: Support for logging out on
GET
requests is deprecated and will be removed in Django 5.0.
-
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.html
if 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
user
keyword argument. The form is responsible for actually changing the user’s password. Defaults toPasswordChangeForm
.
-
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 (seeform_class
above).
-
-
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.html
if 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.
This view will send an email if the following conditions are met:
- The email address provided exists in the system.
- The requested user is active (
User.is_active
isTrue
). - The requested user has a usable password. 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.
If any of these conditions are not met, no email will be sent, 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
PasswordResetForm
and use theform_class
attribute.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.
Attributes:
-
template_name
¶ The full name of a template to use for displaying the password reset form. Defaults to
registration/password_reset_form.html
if 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.html
if 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.txt
if 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 ofdjango.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/html multipart 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 (seeform_class
above) for resetting the user’s password.
Email template context:
email
: An alias foruser.email
user
: The currentUser
, according to theemail
form field. Only active users are able to reset their passwords (User.is_active is True
).site_name
: An alias forsite.name
. If you don’t have the site framework installed, this will be set to the value ofrequest.META['SERVER_NAME']
. For more on sites, see The “sites” framework.domain
: An alias forsite.domain
. If you don’t have the site framework installed, this will be set to the value ofrequest.get_host()
.protocol
: http or httpsuid
: 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
PasswordResetView
doesn’t have an explicitsuccess_url
URL 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.html
if 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 ofdjango.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_login
isTrue
. Required only if you have multipleAUTHENTICATION_BACKENDS
configured. Defaults toNone
.
-
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'
.
Template context:
form
: The form (seeform_class
above) for setting the new user’s password.validlink
: Boolean, True if the link (combination ofuidb64
andtoken
) 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 tosettings.LOGIN_URL
if not supplied.redirect_field_name
: The name of aGET
field containing the URL to redirect to after log out. Overridesnext
if the givenGET
parameter 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
user
as the first positional argument.
-
class
AuthenticationForm
¶ A form for logging a user in.
Takes
request
as its first positional argument, which is stored on the form instance for use by sub-classes.-
confirm_login_allowed
(user)¶ By default,
AuthenticationForm
rejects users whoseis_active
flag is set toFalse
. You may override this behavior with a custom policy to determine which users can log in. Do this with a custom form that subclassesAuthenticationForm
and overrides theconfirm_login_allowed()
method. This method should raise aValidationError
if 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 ValidationError( _("This account is inactive."), code='inactive', ) if user.username.startswith('b'): raise 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 thecontext
with the same variables thatPasswordResetView
passes 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
ModelForm
for creating a new user.It has three fields:
username
(from the user model),password1
, andpassword2
. It verifies thatpassword1
andpassword2
match, validates the password usingvalidate_password()
, and sets the user’s password usingset_password()
.Changed in Django 4.2:In older versions,
UserCreationForm
didn’t save many-to-many form fields for a custom user model.
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.