.. include:: ../README.rst Wait, what? ----------- django-configurations helps you organize the configuration of your Django project by providing the glue code to bridge between Django's module based settings system and programming patterns like mixins_, facades_, factories_ and adapters_ that are useful for non-trivial configuration scenarios. It allows you to use the native abilities of Python inheritance without the side effects of module level namespaces that often lead to the unfortunate use of the ``import *`` anti-pattern. .. _mixins: http://en.wikipedia.org/wiki/Mixin .. _facades: http://en.wikipedia.org/wiki/Facade_pattern .. _factories: http://en.wikipedia.org/wiki/Factory_method_pattern .. _adapters: http://en.wikipedia.org/wiki/Adapter_pattern Okay, how does it work? ----------------------- Any subclass of the ``configurations.Settings`` class will automatically use the values of its class and instance attributes (including properties and methods) to set module level variables of the same module -- that's how Django will interface to the django-configurations based settings during startup and also the reason why it requires you to use its own startup functions. That means when Django starts up django-configurations will have a look at the ``DJANGO_CONFIGURATION`` environment variable to figure out which class in the settings module (as defined by the ``DJANGO_SETTINGS_MODULE`` environment variable) should be used for the process. It then instantiates the class defined with ``DJANGO_CONFIGURATION`` and copies the uppercase attributes to the module level variables. But isn't that magic? --------------------- Yes, it looks like magic, but it's also maintainable and non-intrusive. No monkey patching is needed to teach Django how to load settings via django-configurations because it uses Python import hooks (`PEP 302`_) behind the scenes. .. _`PEP 302`: http://www.python.org/dev/peps/pep-0302/ Usage patterns -------------- There are various configuration patterns that can be implemented with django-configurations. The most common pattern is to have a base class and various subclasses based on the enviroment they are supposed to be used in, e.g. in production, staging and development. Server specific settings ^^^^^^^^^^^^^^^^^^^^^^^^ For example, imagine you have a base setting class in your ``settings.py`` file:: from configurations import Settings class Base(Settings): TIME_ZONE = 'Europe/Berlin' class Dev(Base): DEBUG = True TEMPLATE_DEBUG = DEBUG class Prod(Base): TIME_ZONE = 'America/New_York' You can now set the ``DJANGO_CONFIGURATION`` environment variable to one of the class names you've defined, e.g. on your production server it should be ``Prod``. In bash that would be:: export DJANGO_SETTINGS_MODULE=mysite.settings export DJANGO_CONFIGURATION=Prod Global settings defaults ^^^^^^^^^^^^^^^^^^^^^^^^ Every ``configurations.Settings`` subclass will automatically contain Django's global settings as class attributes, so you can refer to them when setting other values, e.g.:: from configurations import Settings class Base(Settings): TEMPLATE_CONTEXT_PROCESSORS = \ Settings.TEMPLATE_CONTEXT_PROCESSORS + ( 'django.core.context_processors.request', ) @property def LANGUAGES(self): return Settings.LANGUAGES + (('tlh', 'Klingon'),) Mixins ^^^^^^ You might want to apply some configuration values for each and every project you're working on without having to repeat yourself. Just define a few mixin you re-use multiple times:: class FullPageCaching(object): USE_ETAGS = True Then import that mixin class in your site settings module and use it with a Settings class:: from configurations import Settings class AcmeProd(Settings, FullPageCaching): DEBUG = False # ... Thanks ------ - The Pinax_ project for spearheading the efforts to extend the Django project metaphor with reusable project templates and a flexible configuration environment. - `django-classbasedsettings`_ by Matthew Tretter for being the immediate inspiration for django-configurations. .. _Pinax: http://pinaxproject.com .. _`django-classbasedsettings`: https://github.com/matthewwithanm/django-classbasedsettings Bugs and feature requests ------------------------- As always you mileage may vary, so please don't hesitate to send in feature requests and bug reports at the usual place: https://github.com/jezdez/django-configurations/issues Thanks!