===============

Django settings

===============

A Django settings file contains all the configuration of your Django

installation. This document explains how settings work and which settings are

available.

The basics

==========

A settings file is just a Python module with module-level variables.

Here are a couple of example settings::

    DEBUG = False

    DEFAULT_FROM_EMAIL = 'webmaster@example.com'

    TEMPLATE_DIRS = ('/home/templates/mike', '/home/templates/john')

Because a settings file is a Python module, the following apply:

    * It doesn't allow for Python syntax errors.

    * It can assign settings dynamically using normal Python syntax.

      For example::

          MY_SETTING = [str(i) for i in range(30)]

    * It can import values from other settings files.

Designating the settings

========================

When you use Django, you have to tell it which settings you're using. Do this

by using an environment variable, ``DJANGO_SETTINGS_MODULE``.

The value of ``DJANGO_SETTINGS_MODULE`` should be in Python path syntax, e.g.

``mysite.settings``. Note that the settings module should be on the

Python `import search path`_.

.. _import search path: http://diveintopython.org/getting_to_know_python/everything_is_an_object.html

The django-admin.py utility

---------------------------

When using `django-admin.py`_, you can either set the environment variable

once, or explicitly pass in the settings module each time you run the utility.

Example (Unix Bash shell)::

    export DJANGO_SETTINGS_MODULE=mysite.settings

    django-admin.py runserver

Example (Windows shell)::

    set DJANGO_SETTINGS_MODULE=mysite.settings

    django-admin.py runserver

Use the ``--settings`` command-line argument to specify the settings manually::

    django-admin.py runserver --settings=mysite.settings

.. _django-admin.py: ../django_admin/

On the server (mod_python)

--------------------------

In your live server environment, you'll need to tell Apache/mod_python which

settings file to use. Do that with ``SetEnv``::

    <Location "/mysite/">

        SetHandler python-program

        PythonHandler django.core.handlers.modpython

        SetEnv DJANGO_SETTINGS_MODULE mysite.settings

    </Location>

Read the `Django mod_python documentation`_ for more information.

.. _Django mod_python documentation: ../modpython/

Default settings

================

A Django settings file doesn't have to define any settings if it doesn't need

to. Each setting has a sensible default value. These defaults live in the file

``django/conf/global_settings.py``.

Here's the algorithm Django uses in compiling settings:

    * Load settings from ``global_settings.py``.

    * Load settings from the specified settings file, overriding the global

      settings as necessary.

Note that a settings file should *not* import from ``global_settings``, because

that's redundant.

Seeing which settings you've changed

------------------------------------

There's an easy way to view which of your settings deviate from the default

settings. The command ``python manage.py diffsettings`` displays differences

between the current settings file and Django's default settings.

For more, see the `diffsettings documentation`_.

.. _diffsettings documentation: ../django_admin/#diffsettings

Using settings in Python code

=============================

In your Django apps, use settings by importing the object

``django.conf.settings``. Example::

    from django.conf import settings

    if settings.DEBUG:

        # Do something

Note that ``django.conf.settings`` isn't a module -- it's an object. So

importing individual settings is not possible::

    from django.conf.settings import DEBUG  # This won't work.

Also note that your code should *not* import from either ``global_settings`` or

your own settings file. ``django.conf.settings`` abstracts the concepts of

default settings and site-specific settings; it presents a single interface.

It also decouples the code that uses settings from the location of your

settings.

Altering settings at runtime

============================

You shouldn't alter settings in your applications at runtime. For example,

don't do this in a view::

    from django.conf import settings

    settings.DEBUG = True   # Don't do this!

The only place you should assign to settings is in a settings file.

Security

========

Because a settings file contains sensitive information, such as the database

password, you should make every attempt to limit access to it. For example,

change its file permissions so that only you and your Web server's user can

read it. This is especially important in a shared-hosting environment.

Available settings

==================

Here's a full list of all available settings, in alphabetical order, and their

default values.

ABSOLUTE_URL_OVERRIDES

----------------------

Default: ``{}`` (Empty dictionary)

A dictionary mapping ``"app_label.model_name"`` strings to functions that take

a model object and return its URL. This is a way of overriding

``get_absolute_url()`` methods on a per-installation basis. Example::

    ABSOLUTE_URL_OVERRIDES = {

        'blogs.weblog': lambda o: "/blogs/%s/" % o.slug,

        'news.story': lambda o: "/stories/%s/%s/" % (o.pub_year, o.slug),

    }

Note that the model name used in this setting should be all lower-case, regardless

of the case of the actual model class name.

ADMIN_FOR

---------

Default: ``()`` (Empty list)

Used for admin-site settings modules, this should be a tuple of settings

modules (in the format ``'foo.bar.baz'``) for which this site is an admin.

The admin site uses this in its automatically-introspected documentation of

models, views and template tags.

ADMIN_MEDIA_PREFIX

------------------

Default: ``'/media/'``

The URL prefix for admin media -- CSS, JavaScript and images. Make sure to use

a trailing slash.

ADMINS

------

Default: ``()`` (Empty tuple)

A tuple that lists people who get code error notifications. When

``DEBUG=False`` and a view raises an exception, Django will e-mail these people

with the full exception information. Each member of the tuple should be a tuple

of (Full name, e-mail address). Example::

    (('John', 'john@example.com'), ('Mary', 'mary@example.com'))

Note that Django will e-mail *all* of these people whenever an error happens. See the

section on `error reporting via e-mail`_ for more information.

ALLOWED_INCLUDE_ROOTS

---------------------

Default: ``()`` (Empty tuple)

A tuple of strings representing allowed prefixes for the ``{% ssi %}`` template

tag. This is a security measure, so that template authors can't access files

that they shouldn't be accessing.

For example, if ``ALLOWED_INCLUDE_ROOTS`` is ``('/home/html', '/var/www')``,

then ``{% ssi /home/html/foo.txt %}`` would work, but ``{% ssi /etc/passwd %}``

wouldn't.

APPEND_SLASH

------------

Default: ``True``

Whether to append trailing slashes to URLs. This is only used if

``CommonMiddleware`` is installed (see the `middleware docs`_). See also

``PREPEND_WWW``.

CACHE_BACKEND

-------------

Default: ``'simple://'``

The cache backend to use. See the `cache docs`_.

CACHE_MIDDLEWARE_KEY_PREFIX

Default: ``''`` (Empty string)

The cache key prefix that the cache middleware should use. See the

`cache docs`_.

DATABASE_ENGINE

---------------

Default: ``''`` (Empty string)

Which database backend to use. Either ``'postgresql_psycopg2'``, 

``'postgresql'``, ``'mysql'``,  ``'mysql_old'``, ``'sqlite3'`` or

``'ado_mssql'``.

DATABASE_HOST

-------------

Default: ``''`` (Empty string)

Which host to use when connecting to the database. An empty string means

localhost. Not used with SQLite.

If this value starts with a forward slash (``'/'``) and you're using MySQL,

MySQL will connect via a Unix socket to the specified socket. For example::

    DATABASE_HOST = '/var/run/mysql'

If you're using MySQL and this value *doesn't* start with a forward slash, then

this value is assumed to be the host.

DATABASE_NAME

-------------

Default: ``''`` (Empty string)

The name of the database to use. For SQLite, it's the full path to the database

file.

DATABASE_OPTIONS

----------------

Default: ``{}`` (Empty dictionary)

Extra parameters to use when connecting to the database. Consult backend

module's document for available keywords.

DATABASE_PASSWORD

-----------------

Default: ``''`` (Empty string)

The password to use when connecting to the database. Not used with SQLite.

DATABASE_PORT

-------------

Default: ``''`` (Empty string)

The port to use when connecting to the database. An empty string means the

default port. Not used with SQLite.

DATABASE_USER

-------------

Default: ``''`` (Empty string)

The username to use when connecting to the database. Not used with SQLite.

DATE_FORMAT

-----------

Default: ``'N j, Y'`` (e.g. ``Feb. 4, 2003``)

The default formatting to use for date fields on Django admin change-list

pages -- and, possibly, by other parts of the system. See

`allowed date format strings`_.

See also DATETIME_FORMAT, TIME_FORMAT, YEAR_MONTH_FORMAT and MONTH_DAY_FORMAT.

.. _allowed date format strings: ../templates/#now

DATETIME_FORMAT

---------------

Default: ``'N j, Y, P'`` (e.g. ``Feb. 4, 2003, 4 p.m.``)

The default formatting to use for datetime fields on Django admin change-list

pages -- and, possibly, by other parts of the system. See

`allowed date format strings`_.

See also DATE_FORMAT, DATETIME_FORMAT, TIME_FORMAT, YEAR_MONTH_FORMAT and MONTH_DAY_FORMAT.

.. _allowed date format strings: ../templates/#now

DEBUG

-----

Default: ``False``

A boolean that turns on/off debug mode.

If you define custom settings, django/views/debug.py has a ``HIDDEN_SETTINGS``

regular expression which will hide from the DEBUG view anything that contins

``'SECRET``, ``PASSWORD``, or ``PROFANITIES'``. This allows untrusted users to

be able to give backtraces without seeing sensitive (or offensive) settings.

Still, note that there are always going to be sections of your debug output that

are inapporpriate for public consumption. File paths, configuration options, and

the like all give attackers extra information about your server. Never deploy a

site with ``DEBUG`` turned on.

DEFAULT_CHARSET

---------------

Default: ``'utf-8'``

Default charset to use for all ``HttpResponse`` objects, if a MIME type isn't

manually specified. Used with ``DEFAULT_CONTENT_TYPE`` to construct the

``Content-Type`` header.

DEFAULT_CONTENT_TYPE

--------------------

Default: ``'text/html'``

Default content type to use for all ``HttpResponse`` objects, if a MIME type

isn't manually specified. Used with ``DEFAULT_CHARSET`` to construct the

``Content-Type`` header.

DEFAULT_FROM_EMAIL

------------------

Default: ``'webmaster@localhost'``

Default e-mail address to use for various automated correspondence from the

site manager(s).

DISALLOWED_USER_AGENTS

----------------------

Default: ``()`` (Empty tuple)

List of compiled regular expression objects representing User-Agent strings

that are not allowed to visit any page, systemwide. Use this for bad

robots/crawlers.  This is only used if ``CommonMiddleware`` is installed (see

the `middleware docs`_).

EMAIL_HOST

----------

Default: ``'localhost'``

The host to use for sending e-mail.

See also ``EMAIL_PORT``.

EMAIL_HOST_PASSWORD

-------------------

Default: ``''`` (Empty string)

Username to use for the SMTP server defined in ``EMAIL_HOST``. If empty,

Django won't attempt authentication.

See also ``EMAIL_HOST_USER``.

EMAIL_HOST_USER

---------------

Default: ``''`` (Empty string)

Username to use for the SMTP server defined in ``EMAIL_HOST``. If empty,

Django won't attempt authentication.

See also ``EMAIL_HOST_PASSWORD``.

EMAIL_PORT

----------

Default: ``25``

Port to use for the SMTP server defined in ``EMAIL_HOST``.

EMAIL_SUBJECT_PREFIX

--------------------

Default: ``'[Django] '``

Subject-line prefix for e-mail messages sent with ``django.core.mail.mail_admins``

or ``django.core.mail.mail_managers``. You'll probably want to include the

trailing space.

FIXTURE_DIRS

-------------

Default: ``()`` (Empty tuple)

List of locations of the fixture data files, in search order. Note that

these paths should use Unix-style forward slashes, even on Windows. See 

`Testing Django Applications`_.

.. _Testing Django Applications: ../testing/

IGNORABLE_404_ENDS

------------------

Default: ``('mail.pl', 'mailform.pl', 'mail.cgi', 'mailform.cgi', 'favicon.ico', '.php')``

See also ``IGNORABLE_404_STARTS`` and ``Error reporting via e-mail``.

IGNORABLE_404_STARTS

--------------------

Default: ``('/cgi-bin/', '/_vti_bin', '/_vti_inf')``

A tuple of strings that specify beginnings of URLs that should be ignored by

the 404 e-mailer. See ``SEND_BROKEN_LINK_EMAILS``, ``IGNORABLE_404_ENDS`` and

the section on `error reporting via e-mail`_.

INSTALLED_APPS

--------------

Default: ``()`` (Empty tuple)

A tuple of strings designating all applications that are enabled in this Django

installation. Each string should be a full Python path to a Python package that

contains a Django application, as created by `django-admin.py startapp`_.

.. _django-admin.py startapp: ../django_admin/#startapp-appname

INTERNAL_IPS

------------

Default: ``()`` (Empty tuple)

A tuple of IP addresses, as strings, that:

    * See debug comments, when ``DEBUG`` is ``True``

    * Receive X headers if the ``XViewMiddleware`` is installed (see the

      `middleware docs`_)

JING_PATH

---------

Default: ``'/usr/bin/jing'``

Path to the "Jing" executable. Jing is a RELAX NG validator, and Django uses it

to validate each ``XMLField`` in your models.

See http://www.thaiopensource.com/relaxng/jing.html .

LANGUAGE_CODE

-------------

Default: ``'en-us'``

A string representing the language code for this installation. This should be

in standard language format. For example, U.S. English is ``"en-us"``. See the

`internationalization docs`_.

.. _internationalization docs: ../i18n/

LANGUAGES

---------

Default: A tuple of all available languages. Currently, this is::

    LANGUAGES = (

        ('ar', _('Arabic')),

        ('bn', _('Bengali')),

        ('cs', _('Czech')),

        ('cy', _('Welsh')),

        ('da', _('Danish')),

        ('de', _('German')),

        ('el', _('Greek')),

        ('en', _('English')),

        ('es', _('Spanish')),

        ('es_AR', _('Argentinean Spanish')),

        ('fr', _('French')),

        ('gl', _('Galician')),

        ('hu', _('Hungarian')),

        ('he', _('Hebrew')),

        ('is', _('Icelandic')),

        ('it', _('Italian')),

        ('ja', _('Japanese')),

        ('nl', _('Dutch')),

        ('no', _('Norwegian')),

        ('pt-br', _('Brazilian')),

        ('ro', _('Romanian')),

        ('ru', _('Russian')),

        ('sk', _('Slovak')),

        ('sl', _('Slovenian')),

        ('sr', _('Serbian')),

        ('sv', _('Swedish')),