OneToOneModelFactory

factory.py

from django.db import models
from django.utils.importlib import import_module

class OneToOneModelFactory(object):
    """
    creates related models :cls 
    which are subclasses of :subclass named :subclasses

    convenient to define a bunch of related models programmatically 
    (eg. localize table columns in separate tables)

    class Animal(models.Model):
        ...
    class Flying(models.Model):
        wings = models.IntegerField()
        class Meta:
            abstract = True
    ModelSubClassFactory(Animal, Flying, ['Bat', 'Cow'])
    
    registers AnimalBat and AnimalCow models

    """
    def __init__(self, cls, subclass, subclasses):
        self.create_subclasses(cls, subclass, subclasses)

    def create_subclasses(self, cls, subclass, subclasses):
        mod = import_module(cls.__dict__['__module__'], __name__)
        attrs = self.get_subclass_attrs(cls)
        if isinstance(subclass, (list, tuple)):
            subclass_tuple = tuple(subclass)
        else:
            subclass_tuple = (subclass, )
        for sub_cls in subclasses:
            sub_cls_name = self.get_subclass_name(cls, sub_cls)
            model_cls = type(sub_cls_name, subclass_tuple, attrs.copy())
            setattr(mod, sub_cls_name, model_cls)

    def get_subclass_attrs(self, base_class):
        attrs = {
            base_class.__name__.lower(): models.OneToOneField(base_class),
            '__module__': base_class.__dict__['__module__']
        }
        return attrs

    def get_subclass_name(self, cls, subclass):
        return "%s%s" % (cls.__name__, subclass.capitalize())