How to make Django custom user model an abstract class

Question

I have created my own custom user model in django and specified the same in settings.py :

AUTH_USER_MODEL = 'userprofile.User'

After this, I created User as an abstract class since I wanted to have two separate classes derived from this class namely - Vendor and Customer . This will create two separate database tables.

The problem occurs when I created another class - ProductReview . This class needs a foreign key to the user who added the review and this user can be either a Vendor or a Customer . I am not sure how to put this foreign key constraint here, because settings.AUTH_USER_MODEL will not work, as User is an abstract class.

Following is the class structure:

class UserManager(BaseUserManager):

class User(PermissionsMixin, AbstractBaseUser):
    class Meta:
        abstract = True

class Vendor(User):

class Customer(User):

class ProductReview(models.Model):
    user = models.ForeignKey(
        settings.AUTH_USER_MODEL, related_name='reviews', null=True, blank=True)

Edit - I went ahead with three different tables for each of the models.

Answer 1

The declaration of user field in ProductReview model class will map with the USER model. To define whether it is a Vendor or a Customer you need to declare another field probably integer field with mapping declared as

TYPE_OF_USER_MAPPING = {
    1: 'Vendor',
    2: 'Customer'
}

and then create a query to check in which model Vendor or Customer the original USER is.

Answer 2

For your case I would consider changing my modeling. This how I would do it:

• Leave the default User as the auth user model for Django.
• Create a Vendor and a Customer class with one-to-one relationship to the User model in order to extend it.

In this way, a you can have a ProductReview to reference a User , who could be either a Vendor or a Customer , or you can reference Customer s only if you wish.

See more on Django documentation: Extending the User model .