Overview

Override arbitrary Django settings via environment variables.

• Free software: BSD license

tests
package

When to use this package

This package lets you override any Django setting using environment variables, just by adding a couple of lines to the bottom of settings.py.

This is handy if:

• You have a project that is not currently configurable via environment variables, and you want to quickly adapt it to run in an environment like Heroku.
• You want to be able to quickly override settings on deployed code for debugging.

This is not a good idea as the primary way of configuring a complex project in production. In general you'll be happier keeping all settings in source control, and explicitly recording which settings need to be provided by environment variables using django-environ.

Installation

pip install django-env-overrides

Documentation

django-env-overrides lets you quickly adjust an existing Django app to load arbitrary settings from environment variables. It uses django-environ to parse settings from the environment, but allows override of arbitrary settings without specific changes to settings.py.

Setup

Add these lines to the end of your settings.py file:

import django_env_overrides
django_env_overrides.apply_to(globals())

Any environment variable prefixed with DJANGO__ will now be imported to your settings.

Example

settings.py:

DEBUG = True
MEDIA_URL = '/media/'
DATABASES = {
    'default': {
        'ENGINE': 'sqlite3',
    }
}
TEMPLATES = [
    {
        'BACKEND': 'django.template.backends.django.DjangoTemplates',
        'OPTIONS': {
            'context_processors': [
                'django.contrib.auth.context_processors.auth',
            ]
        }
    }
]

import django_env_overrides
django_env_overrides.apply_to(globals())

Environment:

DJANGO__SECRET_KEY=secret
DJANGO__MEDIA_URL=/new_url/
DJANGO__bool__DEBUG=False
POSTGRES=postgres://uf07k1:wegauwhg@ec2-107-21-253-135.compute-1.amazonaws.com:5431/d8r82722
DJANGO__db__DATABASES__default=$POSTGRES
DJANGO__TEMPLATES__0__OPTIONS__context_processors__1='my.context.processor'

Result:

DEBUG = False
MEDIA_URL = '/new_url/'
SECRET_KEY = 'secret'
DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.postgresql_psycopg2',
        'NAME': 'd8r82722',
        'HOST': 'ec2-107-21-253-135.compute-1.amazonaws.com',
        'USER': 'uf07k1',
        'PASSWORD': 'wegauwhg',
        'PORT': 5431,
    }
}
TEMPLATES = [
    {
        'BACKEND': 'django.template.backends.django.DjangoTemplates',
        'OPTIONS': {
            'context_processors': [
                'django.contrib.auth.context_processors.auth',
                'my.context.processor',
            ]
        }
    }
]

Format for environment variables

The format for environment variable names is:

<prefix>__<typecast>__<path>__<to>__<target>__<setting>

<prefix> defaults to DJANGO. If you want to use another prefix, use django_env_overrides.apply_to(globals(), prefix="MYPREFIX").

<typecast> (optional) is any type known to the django-environ package. Currently the supported types are str, bool, int, float, json, list, tuple, dict, url, path, db_url, cache_url, search_url, and email_url. See the django-environ package for usage. If <typecast> is omitted, values are set as str.

<path>__<to>__<target>__<setting> specifies the setting or subsetting the value should be assigned to. Path elements are treated as array indexes if they are integers, and otherwise as dictionary keys.

Development

See CONTRIBUTING.rst