django-configurator

django-configurator eases Django project configuration by relying on the composability of Python classes. It extends the notion of Django’s module based settings loading with well established object oriented programming patterns. This is a port of the django-configurations project which is no longer supported. To replace django-configurations with this project, search and replace all occurrences of “configurations” with “dj_configurator” in your project that you were using django-configurations.

Check out the documentation for more complete examples.

Quickstart

Install django-configurator:

$ python -m pip install django-configurator

or, alternatively, if you want to use URL-based values:

$ python -m pip install django-configurator[cache,database,email,search]

Then subclass the included dj_configurator.Configuration class in your project’s settings.py or any other module you’re using to store the settings constants, e.g.:

# mysite/settings.py

from dj_configurator import Configuration

class Dev(Configuration):
    DEBUG = True

Set the DJANGO_CONFIGURATION environment variable to the name of the class you just created, e.g. in bash:

$ export DJANGO_CONFIGURATION=Dev

and the DJANGO_SETTINGS_MODULE environment variable to the module import path as usual, e.g. in bash:

$ export DJANGO_SETTINGS_MODULE=mysite.settings

Alternatively supply the --configuration option when using Django management commands along the lines of Django’s default --settings command line option, e.g.

$ python -m manage runserver --settings=mysite.settings --configuration=Dev

To enable Django to use your configuration you now have to modify your manage.py, wsgi.py or asgi.py script to use django-configurator’s versions of the appropriate starter functions, e.g. a typical manage.py using django-configurator would look like this:

#!/usr/bin/env python

import os
import sys

if __name__ == "__main__":
    os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'mysite.settings')
    os.environ.setdefault('DJANGO_CONFIGURATION', 'Dev')

    from dj_configurator.management import execute_from_command_line

    execute_from_command_line(sys.argv)

Notice in line 10 we don’t use the common tool django.core.management.execute_from_command_line but instead dj_configurator.management.execute_from_command_line.

The same applies to your wsgi.py file, e.g.:

import os

os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'mysite.settings')
os.environ.setdefault('DJANGO_CONFIGURATION', 'Dev')

from dj_configurator.wsgi import get_wsgi_application

application = get_wsgi_application()

Here we don’t use the default django.core.wsgi.get_wsgi_application function but instead dj_configurator.wsgi.get_wsgi_application.

Or if you are not serving your app via WSGI but ASGI instead, you need to modify your asgi.py file too.:

import os

os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'mysite.settings')
os.environ.setdefault('DJANGO_CONFIGURATION', 'Dev')

from dj_configurator.asgi import get_asgi_application

application = get_asgi_application()

That’s it! You can now use your project with manage.py and your favorite WSGI/ASGI enabled server.

Okay, how does it work?

Any subclass of the dj_configurator.Configuration 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-configurator 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-configurator 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.

Alternatively you can use the --configuration command line option that django-configurator adds to all Django management commands. Behind the scenes it will simply set the DJANGO_CONFIGURATION environment variable so this is purely optional and just there to compliment the default --settings option that Django adds if you prefer that instead of setting environment 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-configurator because it uses Python import hooks (PEP 302) behind the scenes.

Further documentation

• Usage patterns
  • Server specific settings
  • Property settings
  • Global settings defaults
  • Configuration mixins
  • Pristine methods
  • Setup methods
  • Standalone scripts
• Values
  • Overview
  • Environment variables
    • Default behavior
    • Disabling environment variables
    • Custom environment variable names
    • Allow final value to be used outside the configuration context
    • Custom environment variable prefixes
  • Value class
    • Value
  • Built-ins
    • Type values
    • Validator values
    • URL-based values
    • Other values
    • Value mixins
• Cookbook
  • Calling a Django management command
  • Read .env file
  • Envdir
  • Sentry (dynamic setup calls)
  • Celery
    • < 3.1
    • >= 3.1
  • iPython notebooks
  • FastCGI
  • Sphinx
  • Channels
• Changelog
  • v1.0.0

Alternatives

Many thanks to those project that have previously solved these problems:

• 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-configurator.

• django-configurations Jannis Leidel was the original creator and eventually the project was adopted by Jazzband but became defunct due to lack of project management and resurrected and modernised the original projects tools and packaging here.

Bugs and feature requests

As always your mileage may vary, so please don’t hesitate to send feature requests and bug reports:

• https://github.com/UhuruTechnology/django-configurator/issues

Thanks!