Backwards port of Django 5.0's update_or_create function

README.md

Backwards port of Django's 5.0 update_or_create

The update_or_create model function was updated in Django 5.0 with a create_defaults argument that allows only used during create operations.

db.py

import typing as t
from django.db.models import Model


def update_or_create(
    _model: t.Type[Model],
    *,
    defaults: t.Dict[str, t.Any] = None,
    create_defaults: t.Dict[str, t.Any] = None,
    **kwargs,
) -> t.Tuple[Model, bool]:
    '''
    Update or create a model object.

    - You are probably wondering why do we need this when
      Model.objects.update_or_create exists? Well, this one as an extra
      argument, `create_defaults`, which allows us to set the default values
      for a model object when creating it. This was actually introduce in
      Django 5.0, but we are not there yet.
    '''
    defaults = defaults or {}
    create_defaults = create_defaults or {}

    try:
        model_obj = _model.objects.get(**kwargs)

        for key, value in defaults.items():
            setattr(model_obj, key, value)
        model_obj.save()

        created = False
    except _model.DoesNotExist:
        new_values = {**defaults, **create_defaults, **kwargs}
        model_obj = _model(**new_values)
        model_obj.save()

        created = True

    return model_obj, created

test_db.py

from model_bakery import baker
import pytest

from django.contib.auth.models import User


@pytest.mark.django_db
def test_update_or_create__update():
    user = baker.make(
        User,
        first_name='Fin',
        last_name='the Human',
        email='finn@treehouse.ooo',
    )

    expected_user_id = user.pk
    expected_first_name = 'Finn'
    expected_last_name = user.last_name
    expected_email = user.email

    user, user_created = db.update_or_create(
        _model=User,
        defaults={'first_name': expected_first_name},
        create_defaults={'last_name': 'the kho-mein'},
        email=user.email,
    )

    assert user.pk == expected_user_id
    assert user.first_name == expected_first_name
    assert user.last_name == expected_last_name
    assert user.email == expected_email

    assert user_created is False


@pytest.mark.django_db
def test_update_or_create__created():
    expected_first_name = 'Jake'
    expected_last_name = 'the Dog'
    expected_email = 'jake@treehouse.ooo'

    assert User.objects.filter(email=expected_email).count() == 0

    user, user_created = db.update_or_create(
        _model=User,
        defaults={'first_name': expected_first_name},
        create_defaults={'last_name': expected_last_name},
        email=expected_email,
    )

    assert user.email == expected_email
    assert user.first_name == expected_first_name
    assert user.last_name == expected_last_name

    assert user_created is True