``django.contrib.auth``
=======================
This document provides API reference material for the components of Django's
authentication system. For more details on the usage of these components or
how to customize authentication and authorization see the :doc:`authentication
topic guide </topics/auth/index>`.
.. currentmodule:: django.contrib.auth
User
====
Fields
------
.. class:: models.User
:class:`~django.contrib.auth.models.User` objects have the following
fields:
.. attribute:: username
Required. 30 characters or fewer. Usernames may contain alphanumeric,
``_``, ``@``, ``+``, ``.`` and ``-`` characters.
.. attribute:: first_name
Optional. 30 characters or fewer.
.. attribute:: last_name
Optional. 30 characters or fewer.
.. attribute:: email
Optional. Email address.
.. attribute:: password
Required. A hash of, and metadata about, the password. (Django doesn't
store the raw password.) Raw passwords can be arbitrarily long and can
contain any character. See the :doc:`password documentation
</topics/auth/passwords>`.
.. attribute:: groups
Many-to-many relationship to :class:`~django.contrib.auth.models.Group`
.. attribute:: user_permissions
Many-to-many relationship to :class:`~django.contrib.auth.models.Permission`
.. attribute:: is_staff
Boolean. Designates whether this user can access the admin site.
.. attribute:: is_active
Boolean. Designates whether this user account should be considered
active. We recommend that you set this flag to ``False`` instead of
deleting accounts; that way, if your applications have any foreign keys
to users, the foreign keys won't break.
This doesn't necessarily control whether or not the user can log in.
Authentication backends aren't required to check for the ``is_active``
flag, and the default backends do not. If you want to reject a login
based on ``is_active`` being ``False``, it's up to you to check that in
your own login view or a custom authentication backend. However, the
:class:`~django.contrib.auth.forms.AuthenticationForm` used by the
:func:`~django.contrib.auth.views.login` view (which is the default)
*does* perform this check, as do the permission-checking methods such
as :meth:`~django.contrib.auth.models.User.has_perm` and the
authentication in the Django admin. All of those functions/methods will
return ``False`` for inactive users.
.. attribute:: is_superuser
Boolean. Designates that this user has all permissions without
explicitly assigning them.
.. attribute:: last_login
A datetime of the user's last login. Is set to the current date/time by
default.
.. attribute:: date_joined
A datetime designating when the account was created. Is set to the
current date/time by default when the account is created.
Methods
-------
.. class:: models.User
.. method:: get_username()
Returns the username for the user. Since the User model can be swapped
out, you should use this method instead of referencing the username
attribute directly.
.. method:: is_anonymous()
Always returns ``False``. This is a way of differentiating
:class:`~django.contrib.auth.models.User` and
:class:`~django.contrib.auth.models.AnonymousUser` objects.
Generally, you should prefer using
:meth:`~django.contrib.auth.models.User.is_authenticated()` to this
method.
.. method:: is_authenticated()
Always returns ``True`` (as opposed to
``AnonymousUser.is_authenticated()`` which always returns ``False``).
This is a way to tell if the user has been authenticated. This does not
imply any permissions, and doesn't check if the user is active or has
a valid session. Even though normally you will call this method on
``request.user`` to find out whether it has been populated by the
:class:`~django.contrib.auth.middleware.AuthenticationMiddleware`
(representing the currently logged-in user), you should know this method
returns ``True`` for any :class:`~django.contrib.auth.models.User`
instance.
.. method:: get_full_name()
Returns the :attr:`~django.contrib.auth.models.User.first_name` plus
the :attr:`~django.contrib.auth.models.User.last_name`, with a space in
between.
.. method:: get_short_name()
.. versionadded:: 1.5
Returns the :attr:`~django.contrib.auth.models.User.first_name`.
.. method:: set_password(raw_password)
Sets the user's password to the given raw string, taking care of the
password hashing. Doesn't save the
:class:`~django.contrib.auth.models.User` object.
When the ``raw_password`` is ``None``, the password will be set to an
unusable password, as if
:meth:`~django.contrib.auth.models.User.set_unusable_password()`
were used.
.. versionchanged:: 1.6
In Django 1.4 and 1.5, a blank string was unintentionally stored
as an unusable password.
.. method:: check_password(raw_password)
Returns ``True`` if the given raw string is the correct password for
the user. (This takes care of the password hashing in making the
comparison.)
.. versionchanged:: 1.6
In Django 1.4 and 1.5, a blank string was unintentionally
considered to be an unusable password, resulting in this method
returning ``False`` for such a password.
.. method:: set_unusable_password()
Marks the user as having no password set. This isn't the same as
having a blank string for a password.
:meth:`~django.contrib.auth.models.User.check_password()` for this user
will never return ``True``. Doesn't save the
:class:`~django.contrib.auth.models.User` object.
You may need this if authentication for your application takes place
against an existing external source such as an LDAP directory.
.. method:: has_usable_password()
Returns ``False`` if
:meth:`~django.contrib.auth.models.User.set_unusable_password()` has
been called for this user.
.. method:: get_group_permissions(obj=None)
Returns a set of permission strings that the user has, through their
groups.
If ``obj`` is passed in, only returns the group permissions for
this specific object.
.. method:: get_all_permissions(obj=None)
Returns a set of permission strings that the user has, both through
group and user permissions.
If ``obj`` is passed in, only returns the permissions for this
specific object.
.. method:: has_perm(perm, obj=None)
Returns ``True`` if the user has the specified permission, where perm
is in the format ``"<app label>.<permission codename>"``. (see
documentation on :ref:`permissions <topic-authorization>`). If the user is
inactive, this method will always return ``False``.
If ``obj`` is passed in, this method won't check for a permission for
the model, but for this specific object.
.. method:: has_perms(perm_list, obj=None)
Returns ``True`` if the user has each of the specified permissions,
where each perm is in the format
``"<app label>.<permission codename>"``. If the user is inactive,
this method will always return ``False``.
If ``obj`` is passed in, this method won't check for permissions for
the model, but for the specific object.
.. method:: has_module_perms(package_name)
Returns ``True`` if the user has any permissions in the given package
(the Django app label). If the user is inactive, this method will
always return ``False``.
.. method:: email_user(subject, message, from_email=None)
Sends an email to the user. If ``from_email`` is ``None``, Django uses
the :setting:`DEFAULT_FROM_EMAIL`.
.. method:: get_profile()
.. deprecated:: 1.5
With the introduction of :ref:`custom User models <auth-custom-user>`,
the use of :setting:`AUTH_PROFILE_MODULE` to define a single profile
model is no longer supported. See the
:doc:`Django 1.5 release notes</releases/1.5>` for more information.
Returns a site-specific profile for this user. Raises
``django.contrib.auth.models.SiteProfileNotAvailable`` if the
current site doesn't allow profiles, or
:exc:`django.core.exceptions.ObjectDoesNotExist` if the user does not
have a profile.
Manager methods
---------------
.. class:: models.UserManager
The :class:`~django.contrib.auth.models.User` model has a custom manager
that has the following helper methods (in addition to the methods provided
by :class:`~django.contrib.auth.models.BaseUserManager`):
.. method:: create_user(username, email=None, password=None, **extra_fields)
Creates, saves and returns a :class:`~django.contrib.auth.models.User`.
The :attr:`~django.contrib.auth.models.User.username` and
:attr:`~django.contrib.auth.models.User.password` are set as given. The
domain portion of :attr:`~django.contrib.auth.models.User.email` is
automatically converted to lowercase, and the returned
:class:`~django.contrib.auth.models.User` object will have
:attr:`~django.contrib.auth.models.User.is_active` set to ``True``.
If no password is provided,
:meth:`~django.contrib.auth.models.User.set_unusable_password()` will
be called.
The ``extra_fields`` keyword arguments are passed through to the
:class:`~django.contrib.auth.models.User`âs ``__init__`` method to
allow setting arbitrary fields on a :ref:`custom User model
<auth-custom-user>`.
See :ref:`Creating users <topics-auth-creating-users>` for example usage.
.. method:: create_superuser(username, email, password, **extra_fields)
Same as :meth:`create_user`, but sets :attr:`~models.User.is_staff` and
:attr:`~models.User.is_superuser` to ``True``.
Anonymous users
===============
.. class:: models.AnonymousUser
:class:`django.contrib.auth.models.AnonymousUser` is a class that
implements the :class:`django.contrib.auth.models.User` interface, with
these differences:
* :ref:`id <automatic-primary-key-fields>` is always ``None``.
* :attr:`~django.contrib.auth.models.User.is_staff` and
:attr:`~django.contrib.auth.models.User.is_superuser` are always
``False``.
* :attr:`~django.contrib.auth.models.User.is_active` is always ``False``.
* :attr:`~django.contrib.auth.models.User.groups` and
:attr:`~django.contrib.auth.models.User.user_permissions` are always
empty.
* :meth:`~django.contrib.auth.models.User.is_anonymous()` returns ``True``
instead of ``False``.
* :meth:`~django.contrib.auth.models.User.is_authenticated()` returns
``False`` instead of ``True``.
* :meth:`~django.contrib.auth.models.User.set_password()`,
:meth:`~django.contrib.auth.models.User.check_password()`,
:meth:`~django.db.models.Model.save` and
:meth:`~django.db.models.Model.delete()` raise
:exc:`~exceptions.NotImplementedError`.
In practice, you probably won't need to use
:class:`~django.contrib.auth.models.AnonymousUser` objects on your own, but
they're used by Web requests, as explained in the next section.
Permission
==========
.. class:: models.Permission
Fields
------
:class:`~django.contrib.auth.models.Permission` objects have the following
fields:
.. class:: models.Permission
.. attribute:: name
Required. 50 characters or fewer. Example: ``'Can vote'``.
.. attribute:: content_type
Required. A reference to the ``django_content_type`` database table,
which contains a record for each installed model.
.. attribute:: codename
Required. 100 characters or fewer. Example: ``'can_vote'``.
Methods
-------
:class:`~django.contrib.auth.models.Permission` objects have the standard
data-access methods like any other :doc:`Django model </ref/models/instances>`.
Group
=====
.. class:: models.Group
Fields
------
:class:`~django.contrib.auth.models.Group` objects have the following fields:
.. class:: models.Group
.. attribute:: name
Required. 80 characters or fewer. Any characters are permitted. Example:
``'Awesome Users'``.
.. attribute:: permissions
Many-to-many field to :class:`~django.contrib.auth.models.Permission`::
group.permissions = [permission_list]
group.permissions.add(permission, permission, ...)
group.permissions.remove(permission, permission, ...)
group.permissions.clear()
.. _topics-auth-signals:
Login and logout signals
========================
.. module:: django.contrib.auth.signals
The auth framework uses the following :doc:`signals </topics/signals>` that
can be used for notification when a user logs in or out.
.. function:: user_logged_in
Sent when a user logs in successfully.
Arguments sent with this signal:
``sender``
The class of the user that just logged in.
``request``
The current :class:`~django.http.HttpRequest` instance.
``user``
The user instance that just logged in.
.. function:: user_logged_out
Sent when the logout method is called.
``sender``
As above: the class of the user that just logged out or ``None``
if the user was not authenticated.
``request``
The current :class:`~django.http.HttpRequest` instance.
``user``
The user instance that just logged out or ``None`` if the
user was not authenticated.
.. function:: user_login_failed
.. versionadded:: 1.5
Sent when the user failed to login successfully
``sender``
The name of the module used for authentication.
``credentials``
A dictionary of keyword arguments containing the user credentials that were
passed to :func:`~django.contrib.auth.authenticate()` or your own custom
authentication backend. Credentials matching a set of 'sensitive' patterns,
(including password) will not be sent in the clear as part of the signal.
.. _authentication-backends-reference:
Authentication backends
=======================
.. module:: django.contrib.auth.backends
:synopsis: Django's built-in authentication backend classes.
This section details the authentication backends that come with Django. For
information on how to use them and how to write your own authentication
backends, see the :ref:`Other authentication sources section
<authentication-backends>` of the :doc:`User authentication guide
</topics/auth/index>`.
Available authentication backends
---------------------------------
The following backends are available in :mod:`django.contrib.auth.backends`:
.. class:: ModelBackend
This is the default authentication backend used by Django. It
authenticates using credentials consisting of a user identifier and
password. For Django's default user model, the user identifier is the
username, for custom user models it is the field specified by
USERNAME_FIELD (see :doc:`Customizing Users and authentication
</topics/auth/customizing>`).
It also handles the default permissions model as defined for
:class:`~django.contrib.auth.models.User` and
:class:`~django.contrib.auth.models.PermissionsMixin`.
.. class:: RemoteUserBackend
Use this backend to take advantage of external-to-Django-handled
authentication. It authenticates using usernames passed in
:attr:`request.META['REMOTE_USER'] <django.http.HttpRequest.META>`. See
the :doc:`Authenticating against REMOTE_USER </howto/auth-remote-user>`
documentation.
If you need more control, you can create your own authentication backend
that inherits from this class and override these attributes or methods:
.. attribute:: RemoteUserBackend.create_unknown_user
``True`` or ``False``. Determines whether or not a
:class:`~django.contrib.auth.models.User` object is created if not already
in the database. Defaults to ``True``.
.. method:: RemoteUserBackend.authenticate(remote_user)
The username passed as ``remote_user`` is considered trusted. This method
simply returns the ``User`` object with the given username, creating a new
``User`` object if :attr:`~RemoteUserBackend.create_unknown_user` is
``True``.
Returns ``None`` if :attr:`~RemoteUserBackend.create_unknown_user` is
``False`` and a ``User`` object with the given username is not found in the
database.
.. method:: RemoteUserBackend.clean_username(username)
Performs any cleaning on the ``username`` (e.g. stripping LDAP DN
information) prior to using it to get or create a
:class:`~django.contrib.auth.models.User` object. Returns the cleaned
username.
.. method:: RemoteUserBackend.configure_user(user)
Configures a newly created user. This method is called immediately after a
new user is created, and can be used to perform custom setup actions, such
as setting the user's groups based on attributes in an LDAP directory.
Returns the user object.
