django-settingsdict 1.1.1

Simple helper class to handle dict style settings for django app

This is small helper that makes it easier to store distributable django app settings in project settings.py as a dict. Purpose is to keep settings file simple and clean. With this it’s also easier to set defaults for the settings and warn about settings that have been removed.

Helper also supports marking settings that should be imported before returning. Import is done using django.utils.module_loading.import_string.

Helper resolves variables when requested for the first time and caches the value for faster lookup next time. Variables that are not in required or defaults raise AttributeError. If you like to clear the cache, you can use _clear_cached().

Using migrate, you can configure list of migration actions. Parameter takes a list of tuples, where first field is the new setting name, second is the old name outside of the dictionary and optional third is callable. The callable has format migrate_script(old_value: Any, current_dictionary: dict) -> Any, where current_dictionary contains all values read so far.

Design is based on class done in Django REST framework.

Example

Setting defitions in your applications app_settings.py (for example):

from django_settingsdict import SettingsDict
REQUIRED = (
    'IMPORTANT_SETTING',
)
DEFAULTS = {
    'URL_NAME': 'test_app',
    'MIGRATED_VALUE': 'something old, but supported',
    'REVERSE_FUNC': 'django.core.urlresolvers.reverse',
}
IMPORT_STRINGS = (
    'REVERSE_FUNC',
)
REMOVED = (
    'OLD_SETTING',
)
MIGRATE = (
    ('MIGRATED_VALUE', 'MY_APP_OLD_OPTION'),
)
app_settings = SettingsDict('MY_APP',
                            required=REQUIRED,
                            defaults=DEFAULTS,
                            removed=REMOVED,
                            migrate=MIGRATE,
                            import_strings=IMPORT_STRINGS)

Configuration in your projects settings.py:

MY_APP = {
    'IMPORTANT_SETTING': 'some value',
    'URL_NAME': 'test_app_2',
}
MY_APP_OLD_OPTION = 'this is not fixed yet'

And in your application code:

from .app_settings import app_settings

print(app_settings.IMPORTANT_SETTING)
print(app_settings.URL_NAME)
print(app_settings.REVERSE_FUNC)
print(app_settings.MIGRATED_VALUE)

would make following result:

some value
test_app_2
<function reverse at 0x7fd5119e0578>
this is not fixed yet