django-compressor / django-appconf

An app to handle configuration defaults of packaged Django apps gracefully
https://django-appconf.readthedocs.io
BSD 3-Clause "New" or "Revised" License
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django-appconf

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A helper class for handling configuration defaults of packaged Django apps gracefully.

.. note::

This app precedes Django's own AppConfig_ classes that act as
"objects [to] store metadata for an application" inside Django's
app loading mechanism. In other words, they solve a related but
different use case than django-appconf and can't easily be used
as a replacement. The similarity in name is purely coincidental.

.. _AppConfig: https://docs.djangoproject.com/en/stable/ref/applications/#django.apps.AppConfig

Overview

Say you have an app called myapp with a few defaults, which you want to refer to in the app's code without repeating yourself all the time. appconf provides a simple class to implement those defaults. Simply add something like the following code somewhere in your app files:

.. code-block:: python

from appconf import AppConf

class MyAppConf(AppConf):
    SETTING_1 = "one"
    SETTING_2 = (
        "two",
    )

.. note::

``AppConf`` classes depend on being imported during startup of the Django
process. Even though there are multiple modules loaded automatically,
only the ``models`` modules (usually the ``models.py`` file of your
app) are guaranteed to be loaded at startup. Therefore it's recommended
to put your ``AppConf`` subclass(es) there, too.

The settings are initialized with the capitalized app label of where the setting is located at. E.g. if your models.py with the AppConf class is in the myapp package, the prefix of the settings will be MYAPP.

You can override the default prefix by specifying a prefix attribute of an inner Meta class:

.. code-block:: python

from appconf import AppConf

class AcmeAppConf(AppConf):
    SETTING_1 = "one"
    SETTING_2 = (
        "two",
    )

    class Meta:
        prefix = 'acme'

The MyAppConf class will automatically look at Django's global settings to determine if you've overridden it. For example, adding this to your site's settings.py would override SETTING_1 of the above MyAppConf:

.. code-block:: python

ACME_SETTING_1 = "uno"

Since django-appconf completes Django's global settings with its default values (like "one" above), the standard python manage.py diffsettings will show these defaults automatically.

In case you want to use a different settings object instead of the default 'django.conf.settings', set the holder attribute of the inner Meta class to a dotted import path:

.. code-block:: python

from appconf import AppConf

class MyAppConf(AppConf):
    SETTING_1 = "one"
    SETTING_2 = (
        "two",
    )

    class Meta:
        prefix = 'acme'
        holder = 'acme.conf.settings'

If you ship an AppConf class with your reusable Django app, it's recommended to put it in a conf.py file of your app package and import django.conf.settings in it, too:

.. code-block:: python

from django.conf import settings
from appconf import AppConf

class MyAppConf(AppConf):
    SETTING_1 = "one"
    SETTING_2 = (
        "two",
    )

In the other files of your app you can easily make sure the settings are correctly loaded if you import Django's settings object from that module, e.g. in your app's views.py:

.. code-block:: python

from django.http import HttpResponse
from myapp.conf import settings

def index(request):
    text = 'Setting 1 is: %s' % settings.MYAPP_SETTING_1
    return HttpResponse(text)