django-djconfig’s docs

User’s Guide

Installation

Requirements

• Python 2.7, 3.4, 3.5, 3.6 or 3.7
• Django 1.11 LTS, 2.0 or 2.1

Pip

pip install django-djconfig

Configuration

# settings.py

INSTALLED_APPS = [
    # ...

    'djconfig',
]

MIDDLEWARE_CLASSES = [
    # ...

    'djconfig.middleware.DjConfigMiddleware',
]

TEMPLATES = [
    {
        # ...
        'OPTIONS': {
            'context_processors': [
                # ...
                'djconfig.context_processors.config',
            ],
        },
    },
]

Note

Use MIDDLEWARE instead of MIDDLEWARE_CLASSES in Django >= 1.10

Afterwards, run:

python manage.py migrate

All done.

Usage

Creating the config form

Tip

Form’s field names must be unique across forms, so you should prefix them with the name of your app.

# forms.py

from djconfig.forms import ConfigForm


class AppConfigForm(ConfigForm):

    myapp_first_key = forms.BooleanField(initial=True, required=False)
    myapp_second_key = forms.IntegerField(initial=20)

Registering the config form

Tip

Read the django_applications_docs

# apps.py

from django.apps import AppConfig


class MyAppConfig(AppConfig):

    name = 'myapp'
    verbose_name = "Myapp"

    def ready(self):
        self.register_config()
        # ...

    def register_config(self):
        import djconfig
        from .forms import MyConfigForm

        djconfig.register(MyConfigForm)

Accessing the config

from djconfig import config


if config.myapp_first_key:
    # ...

Accessing the config within templates:

# template.html

# ...

{% if config.myapp_first_key %}
    # ...
{% endif %}

Editing the config values

# views.py

@login_required
def config_view(request):
    if not request.user.is_superuser:
        raise Http404

    if request.method == 'POST':
        form = AppConfigForm(data=request.POST)

        if form.is_valid():
            form.save()
            return redirect('/')
    else:
        form = AppConfigForm()

    return render(request, 'app/configuration.html', {'form': form, })

Testing helpers

There is a helper similar to django’s @override_settings that can be used in tests.

# tests.py

from djconfig.utils import override_djconfig

@override_djconfig(myapp_first_key="foo", myapp_second_key="bar")
def test_something(self):
    # ...

Calling djconfig.reload_maybe() is required when unit testing. For example, it may be called within the test’s setUp method to run it before each test. The middleware will call this, so it’s not needed on integration tests that make use of django’s test Client.

# tests.py

import djconfig

def setUp(self):
    djconfig.reload_maybe()

Admin

Register a config form into django admin.

The following example shows how to register a single form that contains all settings:

# admin.py

import djconfig
from .forms import AppConfigForm


class AppConfigAdmin(djconfig.admin.ConfigAdmin):
    change_list_form = AppConfigForm


class AppConfig(djconfig.admin.Config):
    app_label = 'djconfig'
    verbose_name_plural = 'app config'
    name = 'appconfig'

djconfig.admin.register(AppConfig, AppConfigAdmin)

The following example shows how to register a form in multiple apps:

# myapp/admin.py

import djconfig
from .forms import MyAppConfigForm


class MyAppConfigAdmin(djconfig.admin.ConfigAdmin):
    change_list_form = MyAppConfigForm


class MyAppConfig(djconfig.admin.Config):
    app_label = 'myapp'
    verbose_name_plural = 'myapp config'
    name = 'myappconfig'

djconfig.admin.register(MyAppConfig, MyAppConfigAdmin)


# myotherapp/admin.py

import djconfig
from .forms import MyOtherAppConfigForm


class MyOtherAppConfigAdmin(djconfig.admin.ConfigAdmin):
    change_list_form = MyOtherAppConfigForm


class MyOtherAppConfig(djconfig.admin.Config):
    app_label = 'myotherapp'
    verbose_name_plural = 'myotherapp config'
    name = 'myotherappconfig'

djconfig.admin.register(MyOtherAppConfig, MyOtherAppConfigForm)

Cookbook

Save an image

from django import forms
from django.core.files.storage import default_storage
from djconfig.forms import ConfigForm


class MyImageForm(ConfigForm):
    """
        Save an image

        Usage ::

            # on POST, files must be passed
            form = MyImageForm(data=request.POST, files=request.FILES)
            if form.is_valid():
                form.save()
                return redirect('/')

    """

    myapp_image = forms.ImageField(initial=None, required=False)

    def save_image(self):
        image = self.cleaned_data.get('myapp_image')
        if image:
            # `name` may change if the storage renames the file,
            # so we update it `image.name = ...`
            image.name = default_storage.save(image.name, image)

    def save(self):
        self.save_image()
        # the image name will be saved into `conf.myapp_image`
        super(MyImageForm, self).save()

Fields

Supported form fields

The following form fields were tested:

• BooleanField
• CharField
• EmailField
• FloatField
• IntegerField
• URLField
• ChoiceField
• ModelChoiceField
• ModelMultipleChoiceField
• FileField
• ImageField

DateField is not supported at this time (sorry).

Limitations

ChoiceField

The config will always return a string representation of the saved value. It’s up to you to coerce it to the right type (int, float or boolean), which can be done within the clean_my_field method.

Example:

# forms.py

from djconfig.forms import ConfigForm


class AppConfigForm(ConfigForm):

    myapp_choice = forms.ChoiceField(initial=None, choices=[(1, 'label_a'), (2, 'label_b')])

def clean_myapp_choice(self):
    # By doing this, config.myapp_choice
    # will return a int instead of a string
    return int(self.cleaned_data['myapp_choice'])

ModelChoiceField

The config will always return the model instance which is frozen in time to when the config was loaded. If you just need the pk, consider returning it within the clean_my_field method.

The config will return the initial value (usually None), if the previously saved choice is ever deleted from the data base.

to_field_name parameter is not currently supported.

Example:

# forms.py

from djconfig.forms import ConfigForm


class AppConfigForm(ConfigForm):

    myapp_model_choice = forms.ModelChoiceField(initial=None, queryset=MyModel.objects.all())

def clean_myapp_model_choice(self):
    # By doing this, config.myapp_model_choice
    # will return the model instance pk
    # instead of the model instance object
    return self.cleaned_data['myapp_model_choice'].pk

API Reference

API

djconfig module

djconfig.config djconfig.conf.Config object (singleton)

Contain registry of config forms and cache of key-value matching the forms field-value.

All methods are private to avoid clashing with the dynamic attributes.

This should be usually accessed through config

djconfig.register djconfig.conf.Config._register attribute

Register a config form into the registry

Parameters:

• form_class (object) – The form class to register. Must be an instance of djconfig.forms.ConfigForm
• check_middleware (bool) – Check djconfig.middleware.DjConfigMiddleware is registered into settings.MIDDLEWARE_CLASSES. Default True

djconfig.reload_maybe djconfig.conf.Config._reload_maybe attribute

Reload the config if the config model has been updated. This is called once on every request by the middleware. Should not be called directly.

Config Object

class djconfig.conf.Config

Contain registry of config forms and cache of key-value matching the forms field-value.

All methods are private to avoid clashing with the dynamic attributes.

This should be usually accessed through config

ConfigForm Object

class djconfig.forms.ConfigForm(*args, **kwargs)

Base class for every registered config form. It behaves like a regular form.

Inherits from django.forms.Form. The initial attr will be updated with the config values if any.

All form fields implementing this, should have a unique name to avoid clashing with other registered forms, prefixing them with the app name is a good practice.

Parameters:

• args – Positional parameters passed to parent class
• kwargs – Keyword parameters passed to parent class

save()

Save the config with the cleaned data, update the last modified date so the config is reloaded on other process/nodes. Reload the config so it can be called right away.

Template Context Processors

djconfig.context_processors.config(request)

Simple context processor that puts the config into every RequestContext. Just make sure you have a setting like this:

TEMPLATE_CONTEXT_PROCESSORS = (
    # ...
    'djconfig.context_processors.config',
)

Middlewares

class djconfig.middleware.DjConfigMiddleware(get_response=None)

Populate the cache using the database. Reload the cache only if it is not up to date with the config model

Test Helpers

djconfig.utils.override_djconfig(**new_cache_values)

Temporarily override config values.

This is similar to django.test.override_settings(), use it in testing.

Parameters:new_cache_values – Keyword arguments, the key should match one in the config, a new one is created otherwise, the value is overridden within the decorated function

Admin

This module allows to register a config into django’s admin.

Usage:

class FooConfigAdmin(djconfig.admin.ConfigAdmin):
    change_list_form = FooConfigForm


class FooConfig(djconfig.admin.Config):
    app_label = 'djconfig'
    verbose_name_plural = 'foo config'
    name = 'fooconfig'

djconfig.admin.register(FooConfig, FooConfigAdmin)

djconfig.admin.register(conf, conf_admin, **options)

Register a new admin section.

Parameters:

• conf – A subclass of djconfig.admin.Config
• conf_admin – A subclass of djconfig.admin.ConfigAdmin
• options – Extra options passed to django.contrib.admin.site.register

class djconfig.admin.ConfigAdmin(model, admin_site)

A ConfigAdmin is subclass of django.contrib.admin.ModelAdmin.

change_list_form class var must be set to a valid djconfig.forms.ConfigForm subclass

class djconfig.admin.Config

A Config is akin to django’s model Meta class.

app_label must be a valid installed app, 'djconfig' may be used for every registered form, if they don’t belong in a particular app. verbose_name_plural is the title of the admin’s section link, it can be anything. The (app_label, verbose_name_plural, name) must be unique together across registered forms. name is used as the link slug, and it might be used in other places, valid chars are [a-zA-Z_]

Additional Notes

Changelog

0.9.0

• Add django admin panel support

0.8.0

• Drop support for DJango 1.8, 1.9 and 1.10
• Add support for Django 2.1 (no changes were required)
• Adds Python 3.7 support (no changes were required)

0.7.0

• Add: support for ModelMultipleChoiceField

0.6.0

• Add: support for ImageField and FileField PR #27
• Adds Django 1.11 support (no changes were required)
• Adds Django 2.0 support (no changes were required)
• Adds Python 3.6 support (no changes were required)

0.5.3

• Fix: compat for new style middleware (PR #25)

0.5.2

• Adds compat for new style (Django 1.10) middleware (PR #24)

0.5.1

• Adds Django 1.10 support

0.5.0

• Drops Django 1.7 support
• Adds Django 1.9 support
• Adds Python 3.5 support
• Remove config lazy loading
• Adds conf.reload_maybe() to load the config
• Adds app.py config
• Docs

0.4.0

• No longer use django cache
• Renamed DjConfigLocMemMiddleware to DjConfigMiddleware
• DjConfigMiddleware is required

0.3.2

• Fix to never expire keys

0.3.1

• Include missing migrations in setup.py

0.3.0

• Drops support for django 1.5 and 1.6 (for no special reason)
• Support for django 1.8
• Adds migrations
• Raise AttributeError if the config key/attr is not found
• Fix race condition that caused returning non existent values (None) if the config was not fully loaded
• Huge code refactor

0.2.0

• Configuration is lazy loaded, now. This means the database will get queried the first time an option is accessed (ie: `confi.my_first_key`)
• Only config and register are available for importing from the root module djconfig.

License

The MIT License (MIT)

Copyright (c) 2015 Esteban Castro Borsani <ecastroborsani@gmail.com>

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED ‘AS IS’, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.