=============== 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: http://www.djangoproject.com/documentation/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``:: SetHandler python-program PythonHandler django.core.handlers.modpython SetEnv DJANGO_SETTINGS_MODULE mysite.settings Read the `Django mod_python documentation`_ for more information. .. _Django mod_python documentation: http://www.djangoproject.com/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: http://www.djangoproject.com/documentation/django_admin/#diffsettings Using settings in Python code ============================= In your Django apps, use settings by importing them from ``django.conf.settings``. Example:: from django.conf.settings import DEBUG if DEBUG: # Do something 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.settings import DEBUG 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.module_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.blogs': lambda o: "/blogs/%s/" % o.slug, 'news.stories': lambda o: "/stories/%s/%s/" % (o.pub_year, o.slug), } 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')) 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: ``'postgresql'`` Which database backend to use. Either ``'postgresql'``, ``'mysql'``, ``'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_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 and TIME_FORMAT. .. _allowed date format strings: http://www.djangoproject.com/documentation/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 and TIME_FORMAT. .. _allowed date format strings: http://www.djangoproject.com/documentation/templates/#now DEBUG ----- Default: ``False`` A boolean that turns on/off debug mode. 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. ENABLE_PSYCO ------------ Default: ``False`` Whether to enable Psyco, which optimizes Python code. Requires Psyco_. .. _Psyco: http://psyco.sourceforge.net/ IGNORABLE_404_ENDS ------------------ Default: ``('mail.pl', 'mailform.pl', 'mail.cgi', 'mailform.cgi', 'favicon.ico', '.php')`` See also ``IGNORABLE_404_STARTS``. 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`` and ``IGNORABLE_404_ENDS``. 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: http://www.djangoproject.com/documentation/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: http://www.djangoproject.com/documentation/i18n/ LANGUAGES --------- Default: A tuple of all available languages. Currently, this is:: LANGUAGES = ( ('bn', _('Bengali')), ('cs', _('Czech')), ('cy', _('Welsh')), ('da', _('Danish')), ('de', _('German')), ('en', _('English')), ('es', _('Spanish')), ('fr', _('French')), ('gl', _('Galician')), ('is', _('Icelandic')), ('it', _('Italian')), ('no', _('Norwegian')), ('pt-br', _('Brazilian')), ('ro', _('Romanian')), ('ru', _('Russian')), ('sk', _('Slovak')), ('sr', _('Serbian')), ('sv', _('Swedish')), ('zh-cn', _('Simplified Chinese')), ) A tuple of two-tuples in the format (language code, language name). This specifies which languages are available for language selection. See the `internationalization docs`_ for details. Generally, the default value should suffice. Only set this setting if you want to restrict language selection to a subset of the Django-provided languages. MANAGERS -------- Default: ``ADMINS`` (Whatever ``ADMINS`` is set to) A tuple in the same format as ``ADMINS`` that specifies who should get broken-link notifications when ``SEND_BROKEN_LINK_EMAILS=True``. MEDIA_ROOT ---------- Default: ``''`` (Empty string) Absolute path to the directory that holds media for this installation. Example: ``"/home/media/media.lawrence.com/"`` See also ``MEDIA_URL``. MEDIA_URL --------- Default: ``''`` (Empty string) URL that handles the media served from ``MEDIA_ROOT``. Example: ``"http://media.lawrence.com"`` MIDDLEWARE_CLASSES ------------------ Default:: ("django.contrib.sessions.middleware.SessionMiddleware", "django.contrib.auth.middleware.AuthenticationMiddleware", "django.middleware.common.CommonMiddleware", "django.middleware.doc.XViewMiddleware") A tuple of middleware classes to use. See the `middleware docs`_. PREPEND_WWW ----------- Default: ``False`` Whether to prepend the "www." subdomain to URLs that don't have it. This is only used if ``CommonMiddleware`` is installed (see the `middleware docs`_). See also ``APPEND_SLASH``. ROOT_URLCONF ------------ Default: Not defined A string representing the full Python import path to your root URLconf. For example: ``"mydjangoapps.urls"``. See `How Django processes a request`_. .. _How Django processes a request: http://www.djangoproject.com/documentation/url_dispatch/#how-django-processes-a-request SECRET_KEY ---------- Default: ``''`` (Empty string) A secret key for this particular Django installation. Used to provide a seed in secret-key hashing algorithms. Set this to a random string -- the longer, the better. ``django-admin.py startproject`` creates one automatically. SEND_BROKEN_LINK_EMAILS ----------------------- Default: ``False`` Whether to send an e-mail to the ``MANAGERS`` each time somebody visits a Django-powered page that is 404ed with a non-empty referer (i.e., a broken link). This is only used if ``CommonMiddleware`` is installed (see the `middleware docs`_). See also ``IGNORABLE_404_STARTS`` and ``IGNORABLE_404_ENDS``. SERVER_EMAIL ------------ Default: ``'root@localhost'`` The e-mail address that error messages come from, such as those sent to ``ADMINS`` and ``MANAGERS``. SESSION_COOKIE_AGE ------------------ Default: ``1209600`` (2 weeks, in seconds) The age of session cookies, in seconds. See the `session docs`_. SESSION_COOKIE_DOMAIN --------------------- Default: ``None`` The domain to use for session cookies. Set this to a string such as ``".lawrence.com"`` for cross-domain cookies, or use ``None`` for a standard domain cookie. See the `session docs`_. SESSION_COOKIE_NAME ------------------- Default: ``'sessionid'`` The name of the cookie to use for sessions. This can be whatever you want. See the `session docs`_. SESSION_SAVE_EVERY_REQUEST -------------------------- Default: ``False`` Whether to save the session data on every request. See the `session docs`_. SITE_ID ------- Default: Not defined The ID, as an integer, of the current site in the ``django_site`` database table. This is used so that application data can hook into specific site(s) and a single database can manage content for multiple sites. See the `site framework docs`_. .. _site framework docs: http://www.djangoproject.com/documentation/sites/ TEMPLATE_CONTEXT_PROCESSORS --------------------------- Default:: ("django.core.context_processors.auth", "django.core.context_processors.debug", "django.core.context_processors.i18n") A tuple of callables that are used to populate the context in ``RequestContext``. These callables take a request object as their argument and return a dictionary of items to be merged into the context. TEMPLATE_DEBUG -------------- Default: ``False`` A boolean that turns on/off template debug mode. If this is ``True``, the fancy error page will display a detailed report for any ``TemplateSyntaxError``. This report contains the relevant snippet of the template, with the appropriate line highlighted. Note that Django only displays fancy error pages if ``DEBUG`` is ``True``, so you'll want to set that to take advantage of this setting. See also DEBUG. TEMPLATE_DIRS ------------- Default: ``()`` (Empty tuple) List of locations of the template source files, in search order. Note that these paths should use Unix-style forward slashes, even on Windows. See the `template documentation`_. TEMPLATE_LOADERS ---------------- Default: ``('django.template.loaders.filesystem.load_template_source',)`` A tuple of callables (as strings) that know how to import templates from various sources. See the `template documentation`_. TEMPLATE_STRING_IF_INVALID -------------------------- Default: ``''`` (Empty string) Output, as a string, that the template system should use for invalid (e.g. misspelled) variables. See `How invalid variables are handled`_. .. _How invalid variables are handled: http://www.djangoproject.com/documentation/templates_python/#how-invalid-variables-are-handled TIME_FORMAT ----------- Default: ``'P'`` (e.g. ``4 p.m.``) The default formatting to use for time fields on Django admin change-list pages -- and, possibly, by other parts of the system. See `allowed date format strings`_. See also DATE_FORMAT and DATETIME_FORMAT. .. _allowed date format strings: http://www.djangoproject.com/documentation/templates/#now TIME_ZONE --------- Default: ``'America/Chicago'`` A string representing the time zone for this installation. `See available choices`_. Note that this is the time zone to which Django will convert all dates/times -- not necessarily the timezone of the server. For example, one server may serve multiple Django-powered sites, each with a separate time-zone setting. USE_ETAGS --------- Default: ``False`` A boolean that specifies whether to output the "Etag" header. This saves bandwidth but slows down performance. This is only used if ``CommonMiddleware`` is installed (see the `middleware docs`_). .. _cache docs: http://www.djangoproject.com/documentation/cache/ .. _middleware docs: http://www.djangoproject.com/documentation/middleware/ .. _session docs: http://www.djangoproject.com/documentation/sessions/ .. _See available choices: http://www.postgresql.org/docs/current/static/datetime-keywords.html#DATETIME-TIMEZONE-SET-TABLE .. _template documentation: http://www.djangoproject.com/documentation/templates_python/ Creating your own settings ========================== There's nothing stopping you from creating your own settings, for your own Django apps. Just follow these conventions: * Setting names are in all uppercase. * For settings that are sequences, use tuples instead of lists. This is purely for performance. * Don't reinvent an already-existing setting. Using settings without setting DJANGO_SETTINGS_MODULE ===================================================== In some cases, you might want to bypass the ``DJANGO_SETTINGS_MODULE`` environment variable. For example, if you're using the template system by itself, you likely don't want to have to set up an environment variable pointing to a settings module. In these cases, you can configure Django's settings manually. Do this by calling ``django.conf.settings.configure()``. Example:: from django.conf import settings settings.configure(DEBUG=True, TEMPLATE_DEBUG=True, TEMPLATE_DIRS=('/home/web-apps/myapp', '/home/web-apps/base')) Pass ``configure()`` as many keyword arguments as you'd like, with each keyword argument representing a setting and its value. Each argument name should be all uppercase, with the same name as the settings described above. If a particular setting is not passed to ``configure()`` and is needed at some later point, Django will use the default setting value. Custom default settings ----------------------- If you'd like default values to come from somewhere other than ``django.conf.global_settings``, you can pass in a module or class that provides the default settings as the ``default_settings`` argument (or as the first positional argument) in the call to ``configure()``. In this example, default settings are taken from ``myapp_defaults``, and the ``DEBUG`` setting is set to ``True``, regardless of its value in ``myapp_defaults``:: from django.conf import settings from myapp import myapp_defaults settings.configure(default_settings=myapp_defaults, DEBUG=True) The following example, which uses ``myapp_defaults`` as a positional argument, is equivalent:: settings.configure(myapp_defaults, DEBUG = True) Normally, you will not need to override the defaults in this fashion. The Django defaults are sufficiently tame that you can safely use them. Be aware that if you do pass in a new default module, it entirely *replaces* the Django defaults, so you must specify a value for every possible setting that might be used in that code you are importing. Check in ``django.conf.settings.global_settings`` for the full list. Either configure() or DJANGO_SETTINGS_MODULE is required -------------------------------------------------------- If you're not setting the ``DJANGO_SETTINGS_MODULE`` environment variable, you *must* call ``configure()`` at some point before using any code that reads settings. If you don't set ``DJANGO_SETTINGS_MODULE`` and don't call ``configure()``, Django will raise an ``EnvironmentError`` exception the first time a setting is accessed. If you set ``DJANGO_SETTINGS_MODULE``, access settings values somehow, *then* call ``configure()``, Django will raise an ``EnvironmentError`` saying settings have already been configured. Also, it's an error to call ``configure()`` more than once, or to call ``configure()`` after any setting has been accessed. It boils down to this: Use exactly one of either ``configure()`` or ``DJANGO_SETTINGS_MODULE``. Not both, and not neither.