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:

• username
• password
• email
• first_name
• last_name

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', '[email protected]', '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 protected]

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 and password for the default case, checks them against each authentication backend, and returns a User object 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

request is an optional HttpRequest which 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 simple 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.

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 an HttpRequest object and a User 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() 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:

1. Use the value of the optional backend argument, if provided.
2. Use the value of the user.backend attribute, if present. This allows pairing authenticate() and login(): authenticate() sets the user.backend attribute on the user object it returns.
3. Use the backend in AUTHENTICATION_BACKENDS, if there is only one.
4. 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(), use django.contrib.auth.logout() within your view. It takes an HttpRequest 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 calling django.contrib.auth.logout().

Limiting access to logged-in users

The raw way

The simple, 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) [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 optional redirect_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 of redirect_field_name as its key rather than "next" (the default).

login_required() also takes an optional login_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 the settings.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.

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_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'

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.

The simple way is to 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 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 User object and returns True if the user is allowed to view the page. Note that user_passes_test() does not automatically check that the User 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 to None 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 of AccessMixin 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 of test_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 call super() 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.can_vote')
def my_view(request):
    ...

Just like the has_perm() method, permission names take the form "<app label>.<permission codename>" (i.e. polls.can_vote for a permission on a model in the polls 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 optional login_url parameter:

from django.contrib.auth.decorators import permission_required

@permission_required('polls.can_vote', login_url='/loginpage/')
def my_view(request):
    ...

As in the login_required() decorator, login_url defaults to settings.LOGIN_URL.

If the raise_exception parameter 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_exception but 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.can_vote', raise_exception=True)
def my_view(request):
    ...

This also avoids a redirect loop when LoginView’s redirect_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 the permission_required parameter:

from django.contrib.auth.mixins import PermissionRequiredMixin

class MyView(PermissionRequiredMixin, View):
    permission_required = 'polls.can_vote'
    # Or multiple of permissions:
    permission_required = ('polls.can_open', 'polls.can_edit')

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 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 None in 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 PermissionDenied exception 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_url if set, or settings.LOGIN_URL otherwise.

get_permission_denied_message()

When raise_exception is 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_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 the redirect_field_name attribute by default.

handle_no_permission()

Depending on the value of raise_exception, the method either raises a PermissionDenied exception or redirects the user to the login_url, optionally including the redirect_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:
        ...

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 GET field containing the URL to redirect to after login. Defaults to next.
• authentication_form: A callable (typically just 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 the permission_required() decorator unless the raise_exception parameter is used.

• success_url_allowed_hosts: A set of hosts, in addition to request.get_host(), that are safe for redirecting after login. Defaults to an empty set.

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 in next. If next isn’t provided, it redirects to settings.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: A Form object 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_ID setting. 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_name parameter via the extra arguments to the as_view method in your URLconf. For example, this URLconf line would use myapp/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 using redirect_field_name. By default, the field is called next.

Here’s a sample registration/login.html template you can use as a starting point. It assumes you have a base.html template that defines a content 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 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_form attribute. This form must accept a request keyword 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 GET field containing the URL to redirect to after log out. Defaults to next. Overrides the next_page URL if the given GET 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 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_ID setting. 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_URL if 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.html if not supplied.
• success_url: The URL to redirect to after a successful password change.
• 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 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_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.

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 PasswordResetForm and use the form_class attribute.

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.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 of django.contrib.auth.tokens.PasswordResetTokenGenerator.
• success_url: The URL to redirect to after a successful password reset request.
• 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 (see form_class above) for resetting the user’s password.

Email template context:

• email: An alias for user.email
• user: The current User, according to the email form 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 PasswordResetView doesn’t have an explicit success_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 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_login is True. Required only if you have multiple AUTHENTICATION_BACKENDS configured. 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.

Template context:

• form: The form (see form_class above) for setting the new user’s password.
• validlink: Boolean, True if the link (combination of uidb64 and 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_URL if not supplied.
• redirect_field_name: The name of a GET field containing the URL to redirect to after log out. Overrides next if the given GET 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:

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 whose is_active flag 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 AuthenticationForm and overrides the confirm_login_allowed() method. This method should raise a ValidationError 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 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, and html_email_template (if it is not None). 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 context with the same variables that PasswordResetView 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, and password2. It verifies that password1 and password2 match, 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.

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.can_vote:

{% if perms.foo.can_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.can_vote %}
        <p>You can vote!</p>
    {% endif %}
    {% if perms.foo.can_drive %}
        <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.can_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.