Custom User model

Added in version 1.1

Django comes with the ability to customize default auth.User model - either by subclassing AbstractUser or defining very own class. This can be very powerful; it must be done with caution, though. Basically, if we subclass AbstractUser or define many-to-many relation with auth.Group (and give reverse relate name groups) we should be fine.

By default, django-guardian monkey patches the user model to add some needed functionality. This can result in errors if guardian is imported into the models.py of the same app where the custom user model lives.

To fix this, it is recommended to add the setting GUARDIAN_MONKEY_PATCH_USER = False in your settings.py and subclass guardian.mixins.GuardianUserMixin in your custom user model.

important

django-guardian relies heavily on the auth.User model. Specifically it was build from the ground-up with relation between auth.User and auth.Group models. Retaining this relation is crucial for guardian - without many to many User (custom or default) and auth.Group relation django-guardian will BREAK.

See Also

Read more about customizing the Django User model

Anonymous user creation

It is also possible to override default behavior of how instance for anonymous user is created. In example, let's imagine we have our user model as follows:

from django.contrib.auth.models import AbstractUser
from django.db import models


class CustomUser(AbstractUser):
    real_username = models.CharField(max_length=120, unique=True)
    birth_date = models.DateField()  # field without default value

    USERNAME_FIELD = 'real_username'

Note that there is a birth_date field defined at the model and it does not have a default value. It would fail to create anonymous user instance as default implementation cannot know anything about CustomUser model.

In order to override the way anonymous instance is created we need to make GUARDIAN_GET_INIT_ANONYMOUS_USER pointing at our custom implementation. In example, let's define our init function:

import datetime


def get_anonymous_user_instance(User):
    return User(real_username='Anonymous', birth_date=datetime.date(1970, 1, 1))

and put it at myapp/models.py. Last step is to set proper configuration in our settings module:

GUARDIAN_GET_INIT_ANONYMOUS_USER = 'myapp.models.get_anonymous_user_instance'

If the field type of the our custom User class is not a CharField, we need to override the default value that the anonymous user is instantiated with. We can override this value by setting ANONYMOUS_DEFAULT_USERNAME_VALUE to a proper non-string default value, in our settings module:

ANONYMOUS_DEFAULT_USERNAME_VALUE = non_string_object_value