django/contrib/auth/models.py
from collections.abc import Iterable
from django.apps import apps
from django.contrib import auth
from django.contrib.auth.base_user import AbstractBaseUser, BaseUserManager
from django.contrib.auth.hashers import make_password
from django.contrib.contenttypes.models import ContentType
from django.core.exceptions import PermissionDenied
from django.core.mail import send_mail
from django.db import models
from django.db.models.manager import EmptyManager
from django.utils import timezone
from django.utils.translation import gettext_lazy as _
from .validators import UnicodeUsernameValidator
def update_last_login(sender, user, **kwargs):
"""
A signal receiver which updates the last_login date for
the user logging in.
"""
user.last_login = timezone.now()
user.save(update_fields=["last_login"])
class PermissionManager(models.Manager):
use_in_migrations = True
def get_by_natural_key(self, codename, app_label, model):
return self.get(
codename=codename,
content_type=ContentType.objects.db_manager(self.db).get_by_natural_key(
app_label, model
),
)
class Permission(models.Model):
"""
The permissions system provides a way to assign permissions to specific
users and groups of users.
The permission system is used by the Django admin site, but may also be
useful in your own code. The Django admin site uses permissions as follows:
- The "add" permission limits the user's ability to view the "add" form
and add an object.
- The "change" permission limits a user's ability to view the change
list, view the "change" form and change an object.
- The "delete" permission limits the ability to delete an object.
- The "view" permission limits the ability to view an object.
Permissions are set globally per type of object, not per specific object
instance. It is possible to say "Mary may change news stories," but it's
not currently possible to say "Mary may change news stories, but only the
ones she created herself" or "Mary may only change news stories that have a
certain status or publication date."
The permissions listed above are automatically created for each model.
"""
name = models.CharField(_("name"), max_length=255)
content_type = models.ForeignKey(
ContentType,
models.CASCADE,
verbose_name=_("content type"),
)
codename = models.CharField(_("codename"), max_length=100)
objects = PermissionManager()
class Meta:
verbose_name = _("permission")
verbose_name_plural = _("permissions")
unique_together = [["content_type", "codename"]]
ordering = ["content_type__app_label", "content_type__model", "codename"]
def __str__(self):
return "%s | %s" % (self.content_type, self.name)
def natural_key(self):
return (self.codename,) + self.content_type.natural_key()
natural_key.dependencies = ["contenttypes.contenttype"]
class GroupManager(models.Manager):
"""
The manager for the auth's Group model.
"""
use_in_migrations = True
def get_by_natural_key(self, name):
return self.get(name=name)
class Group(models.Model):
"""
Groups are a generic way of categorizing users to 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 all 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
apply some label, or extended functionality, to them. For example, you
could create a group 'Special users', and you could write code that would
do special things to those users -- such as giving them access to a
members-only portion of your site, or sending them members-only email
messages.
"""
name = models.CharField(_("name"), max_length=150, unique=True)
permissions = models.ManyToManyField(
Permission,
verbose_name=_("permissions"),
blank=True,
)
objects = GroupManager()
class Meta:
verbose_name = _("group")
verbose_name_plural = _("groups")
def __str__(self):
return self.name
def natural_key(self):
return (self.name,)
class UserManager(BaseUserManager):
use_in_migrations = True
def _create_user(self, username, email, password, **extra_fields):
"""
Create and save a user with the given username, email, and password.
"""
if not username:
raise ValueError("The given username must be set")
email = self.normalize_email(email)
# Lookup the real model class from the global app registry so this
# manager method can be used in migrations. This is fine because
# managers are by definition working on the real model.
GlobalUserModel = apps.get_model(
self.model._meta.app_label, self.model._meta.object_name
)
username = GlobalUserModel.normalize_username(username)
user = self.model(username=username, email=email, **extra_fields)
user.password = make_password(password)
user.save(using=self._db)
return user
def create_user(self, username, email=None, password=None, **extra_fields):
extra_fields.setdefault("is_staff", False)
extra_fields.setdefault("is_superuser", False)
return self._create_user(username, email, password, **extra_fields)
def create_superuser(self, username, email=None, password=None, **extra_fields):
extra_fields.setdefault("is_staff", True)
extra_fields.setdefault("is_superuser", True)
if extra_fields.get("is_staff") is not True:
raise ValueError("Superuser must have is_staff=True.")
if extra_fields.get("is_superuser") is not True:
raise ValueError("Superuser must have is_superuser=True.")
return self._create_user(username, email, password, **extra_fields)
def with_perm(
self, perm, is_active=True, include_superusers=True, backend=None, obj=None
):
if backend is None:
backends = auth._get_backends(return_tuples=True)
if len(backends) == 1:
backend, _ = backends[0]
else:
raise ValueError(
"You have multiple authentication backends configured and "
"therefore must provide the `backend` argument."
)
elif not isinstance(backend, str):
raise TypeError(
"backend must be a dotted import path string (got %r)." % backend
)
else:
backend = auth.load_backend(backend)
if hasattr(backend, "with_perm"):
return backend.with_perm(
perm,
is_active=is_active,
include_superusers=include_superusers,
obj=obj,
)
return self.none()
# A few helper functions for common logic between User and AnonymousUser.
def _user_get_permissions(user, obj, from_name):
permissions = set()
name = "get_%s_permissions" % from_name
for backend in auth.get_backends():
if hasattr(backend, name):
permissions.update(getattr(backend, name)(user, obj))
return permissions
def _user_has_perm(user, perm, obj):
"""
A backend can raise `PermissionDenied` to short-circuit permission checking.
"""
for backend in auth.get_backends():
if not hasattr(backend, "has_perm"):
continue
try:
if backend.has_perm(user, perm, obj):
return True
except PermissionDenied:
return False
return False
def _user_has_module_perms(user, app_label):
"""
A backend can raise `PermissionDenied` to short-circuit permission checking.
"""
for backend in auth.get_backends():
if not hasattr(backend, "has_module_perms"):
continue
try:
if backend.has_module_perms(user, app_label):
return True
except PermissionDenied:
return False
return False
class PermissionsMixin(models.Model):
"""
Add the fields and methods necessary to support the Group and Permission
models using the ModelBackend.
"""
is_superuser = models.BooleanField(
_("superuser status"),
default=False,
help_text=_(
"Designates that this user has all permissions without "
"explicitly assigning them."
),
)
groups = models.ManyToManyField(
Group,
verbose_name=_("groups"),
blank=True,
help_text=_(
"The groups this user belongs to. A user will get all permissions "
"granted to each of their groups."
),
related_name="user_set",
related_query_name="user",
)
user_permissions = models.ManyToManyField(
Permission,
verbose_name=_("user permissions"),
blank=True,
help_text=_("Specific permissions for this user."),
related_name="user_set",
related_query_name="user",
)
class Meta:
abstract = True
def get_user_permissions(self, obj=None):
"""
Return a list of permission strings that this user has directly.
Query all available auth backends. If an object is passed in,
return only permissions matching this object.
"""
return _user_get_permissions(self, obj, "user")
def get_group_permissions(self, obj=None):
"""
Return a list of permission strings that this user has through their
groups. Query all available auth backends. If an object is passed in,
return only permissions matching this object.
"""
return _user_get_permissions(self, obj, "group")
def get_all_permissions(self, obj=None):
return _user_get_permissions(self, obj, "all")
def has_perm(self, perm, obj=None):
"""
Return True if the user has the specified permission. Query all
available auth backends, but return immediately if any backend returns
True. Thus, a user who has permission from a single auth backend is
assumed to have permission in general. If an object is provided, check
permissions for that object.
"""
# Active superusers have all permissions.
if self.is_active and self.is_superuser:
return True
# Otherwise we need to check the backends.
return _user_has_perm(self, perm, obj)
def has_perms(self, perm_list, obj=None):
"""
Return True if the user has each of the specified permissions. If
object is passed, check if the user has all required perms for it.
"""
if not isinstance(perm_list, Iterable) or isinstance(perm_list, str):
raise ValueError("perm_list must be an iterable of permissions.")
return all(self.has_perm(perm, obj) for perm in perm_list)
def has_module_perms(self, app_label):
"""
Return True if the user has any permissions in the given app label.
Use similar logic as has_perm(), above.
"""
# Active superusers have all permissions.
if self.is_active and self.is_superuser:
return True
return _user_has_module_perms(self, app_label)
class AbstractUser(AbstractBaseUser, PermissionsMixin):
"""
An abstract base class implementing a fully featured User model with
admin-compliant permissions.
Username and password are required. Other fields are optional.
"""
username_validator = UnicodeUsernameValidator()
username = models.CharField(
_("username"),
max_length=150,
unique=True,
help_text=_(
"Required. 150 characters or fewer. Letters, digits and @/./+/-/_ only."
),
validators=[username_validator],
error_messages={
"unique": _("A user with that username already exists."),
},
)
first_name = models.CharField(_("first name"), max_length=150, blank=True)
last_name = models.CharField(_("last name"), max_length=150, blank=True)
email = models.EmailField(_("email address"), blank=True)
is_staff = models.BooleanField(
_("staff status"),
default=False,
help_text=_("Designates whether the user can log into this admin site."),
)
is_active = models.BooleanField(
_("active"),
default=True,
help_text=_(
"Designates whether this user should be treated as active. "
"Unselect this instead of deleting accounts."
),
)
date_joined = models.DateTimeField(_("date joined"), default=timezone.now)
objects = UserManager()
EMAIL_FIELD = "email"
USERNAME_FIELD = "username"
REQUIRED_FIELDS = ["email"]
class Meta:
verbose_name = _("user")
verbose_name_plural = _("users")
abstract = True
def clean(self):
super().clean()
self.email = self.__class__.objects.normalize_email(self.email)
def get_full_name(self):
"""
Return the first_name plus the last_name, with a space in between.
"""
full_name = "%s %s" % (self.first_name, self.last_name)
return full_name.strip()
def get_short_name(self):
"""Return the short name for the user."""
return self.first_name
def email_user(self, subject, message, from_email=None, **kwargs):
"""Send an email to this user."""
send_mail(subject, message, from_email, [self.email], **kwargs)
class User(AbstractUser):
"""
Users within the Django authentication system are represented by this
model.
Username and password are required. Other fields are optional.
"""
class Meta(AbstractUser.Meta):
swappable = "AUTH_USER_MODEL"
class AnonymousUser:
id = None
pk = None
username = ""
is_staff = False
is_active = False
is_superuser = False
_groups = EmptyManager(Group)
_user_permissions = EmptyManager(Permission)
def __str__(self):
return "AnonymousUser"
def __eq__(self, other):
return isinstance(other, self.__class__)
def __hash__(self):
return 1 # instances always return the same hash value
def __int__(self):
raise TypeError(
"Cannot cast AnonymousUser to int. Are you trying to use it in place of "
"User?"
)
def save(self):
raise NotImplementedError(
"Django doesn't provide a DB representation for AnonymousUser."
)
def delete(self):
raise NotImplementedError(
"Django doesn't provide a DB representation for AnonymousUser."
)
def set_password(self, raw_password):
raise NotImplementedError(
"Django doesn't provide a DB representation for AnonymousUser."
)
def check_password(self, raw_password):
raise NotImplementedError(
"Django doesn't provide a DB representation for AnonymousUser."
)
@property
def groups(self):
return self._groups
@property
def user_permissions(self):
return self._user_permissions
def get_user_permissions(self, obj=None):
return _user_get_permissions(self, obj, "user")
def get_group_permissions(self, obj=None):
return set()
def get_all_permissions(self, obj=None):
return _user_get_permissions(self, obj, "all")
def has_perm(self, perm, obj=None):
return _user_has_perm(self, perm, obj=obj)
def has_perms(self, perm_list, obj=None):
if not isinstance(perm_list, Iterable) or isinstance(perm_list, str):
raise ValueError("perm_list must be an iterable of permissions.")
return all(self.has_perm(perm, obj) for perm in perm_list)
def has_module_perms(self, module):
return _user_has_module_perms(self, module)
@property
def is_anonymous(self):
return True
@property
def is_authenticated(self):
return False
def get_username(self):
return self.username