Django IoC

ipython.py

In [1]: from django.conf import settings
   ...: from django.utils.module_loading import import_string
   ...:
   ...:
   ...: class ServiceFactory:
   ...:     def __init__(self, django_setting):
   ...:         self._django_setting = django_setting
   ...:
   ...:     def __call__(self, import_str=None):
   ...:         if import_str is None:
   ...:             import_str = getattr(settings, self._django_setting)
   ...:         return import_string(import_str)
   ...:
   ...:
   ...: # setting SNS_BACKEND='adapters.sns_adapter.sns'
   ...: get_sns_service = ServiceFactory('SNS_BACKEND')
   ...:

In [2]: get_sns_service()
Out[2]: <module 'adapters.sns_adapter.sns' from '/code/adapters/sns_adapter/sns.py'>

In [3]: get_sns_service('adapters.sns_adapter.dummy')
Out[3]: <module 'adapters.sns_adapter.dummy' from '/code/adapters/sns_adapter/dummy.py'>