Assign clients to seller

Question

In my application there are two types of users, sellers and clients. Each client must be assigned to exactly one seller but a seller can have multiple clients.

I have created one usermodel, so all my users are saved in the same place. In the model there is a boolean field called "is_seller" and another boolean field called "is_client". These get set to true depending on which registration form the user use.

The client must be assigned when they register but I am not able to get my head around how I should implement this logic. I would appreciate all sorts of guidance!

Answer 1

If I were you I'd do something like:

class Person(models.Model):
    class Meta:
        abstract = True
    user = models.OneToOne(User, on_delete=models.CASCADE)

    def is_seller(self):
        return hasattr(self, 'seller')

    def is_client(self):
        return hasattr(self, 'client')

class Seller(Person):
    pass

class Client(Person):
    seller = models.ForeignKey(Seller,
                               on_delete=models.CASCADE,
                               related_name="clients")

So from this you can do this:

# example to read a person:
p = Person.objects.get(pk=1)
# if he's a seller, display all his clients:
if p.is_seller():
    for client in p.clients.all():
        print(f"Seller {p} has this client: {client}")

And the opposite: if he's a client, display his seller

# example to read a person:
p = Person.objects.get(pk=1)
# if he's a client, display all his seller:
if p.is_client():
    print(f"Client {p} has this seller: {p.seller}")

I didn't test it but it's very close to a well-tested code.