django.core.exceptions.FieldDoesNotExist: User has no field named 'username'

Question

I'm trying to customize django's AbstractUser. When I try to reset username to None, I get the following exception:

"django.core.exceptions.FieldDoesNotExist: User has no field named 'username'".

Here is my code:

class UserManager(BaseUserManager):
    use_in_migrations = True

    def _create_user(self, email, password, **extra_fields):
        if not email:
            raise ValueError("L'adresse e-mail donnée doit etre definie")
        email = self.normalize_email(email)
        user = self.model(email=email, **extra_fields)
        user.set_password(password)
        user.save(using=self._db)
        return user

    def create_user(self, email, password, **extra_fields):
        extra_fields.setdefault("is_staff", False)
        extra_fields.setdefault("is_superuser", False)
        return self._create_user(email, password, **extra_fields)

    def create_superuser(self, email, password, **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(email, password, **extra_fields)


class User(AbstractUser):
    username = None
    email = models.EmailField('email adress', unique=True)
    telephone = models.CharField(max_length=20)
    REQUIRED_FIELDS = []

What can I do to solve this problem?

Answer 1

You haven't set a value for USERNAME_FIELD in your code. This must be set to a field that uniquely identifies a user instance. AbstractUser sets this to 'username' and hence you are getting the error. You can set this to 'email' to solve your problem:

class User(AbstractUser):
    username = None
    email = models.EmailField('email adress', unique=True)
    telephone = models.CharField(max_length=20)
    # set below value
    USERNAME_FIELD = 'email'
    REQUIRED_FIELDS = []

Answer 2

This might have also caused if you are using django-allauth in your project.To fix this you need to define ACCOUNT_USER_MODEL_USERNAME_FIELD to None inside settings.py. Refer this question and allauth documentation for more information.

ACCOUNT_USER_MODEL_USERNAME_FIELD = None

Answer 3

What's the reason to set username as None?

User model must has a unique field like a username or email or phone_number to identificate user.

If you want to override user's model, you should to provide such unique field, mark it as username field and set django settings variable AUTH_USER_MODEL defining your customized model.

Something like this:

# model
class User(AbstractUser):
    username = models.CharField(max_length=32, unique=True)  # or something else
    ...

    USERNAME_FIELD = 'username'


# settings
AUTH_USER_MODEL = 'users.User'