django1/docs/flatpages.txt

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=================
The flatpages app
=================
Django comes with an optional "flatpages" application. It lets you store simple
"flat" HTML content in a database and handles the management for you via
Django's admin interface and a Python API.
A flatpage is a simple object with a URL, title and content. Use it for
one-off, special-case pages, such as "About" or "Privacy Policy" pages, that
you want to store in a database but for which you don't want to develop a
custom Django application.
A flatpage can use a custom template or a default, systemwide flatpage
template. It can be associated with one, or multiple, sites.
Here are some examples of flatpages on Django-powered sites:
* http://www.chicagocrime.org/about/
* http://www.lawrence.com/about/contact/
Installation
============
To install the flatpages app, follow these steps:
1. Install the `sites framework`_ by adding ``'django.contrib.sites'`` to
your INSTALLED_APPS_ setting, if it's not already in there.
2. Add ``'django.contrib.flatpages'`` to your INSTALLED_APPS_ setting.
3. Add ``'django.contrib.flatpages.middleware.FlatpageFallbackMiddleware'``
to your MIDDLEWARE_CLASSES_ setting.
4. Run the command ``manage.py syncdb``.
.. _sites framework: ../sites/
.. _INSTALLED_APPS: ../settings/#installed-apps
.. _MIDDLEWARE_CLASSES: ../settings/#middleware-classes
How it works
============
``manage.py syncdb`` creates two tables in your database: ``django_flatpage``
and ``django_flatpage_sites``. ``django_flatpage`` is a simple lookup table
that simply maps a URL to a title and bunch of text content.
``django_flatpage_sites`` associates a flatpage with a site.
The ``FlatpageFallbackMiddleware`` does all of the work. Each time any Django
application raises a 404 error, this middleware checks the flatpages database
for the requested URL as a last resort. Specifically, it checks for a flatpage
with the given URL with a site ID that corresponds to the SITE_ID_ setting.
If it finds a match, it follows this algorithm:
* If the flatpage has a custom template, it loads that template. Otherwise,
it loads the template ``flatpages/default.html``.
* It passes that template a single context variable, ``flatpage``, which is
the flatpage object. It uses RequestContext_ in rendering the template.
If it doesn't find a match, the request continues to be processed as usual.
The middleware only gets activated for 404s -- not for 500s or responses of any
other status code.
Note that the order of ``MIDDLEWARE_CLASSES`` matters. Generally, you can put
``FlatpageFallbackMiddleware`` at the end of the list, because it's a last
resort.
For more on middleware, read the `middleware docs`_.
.. _SITE_ID: ../settings/#site-id
.. _RequestContext: ../templates_python/#subclassing-context-djangocontext
.. _middleware docs: ../middleware/
How to add, change and delete flatpages
=======================================
Via the admin interface
-----------------------
If you've activated the automatic Django admin interface, you should see a
"Flatpages" section on the admin index page. Edit flatpages as you edit any
other object in the system.
Via the Python API
------------------
Flatpages are represented by a standard `Django model`_, which lives in
`django/contrib/flatpages/models.py`_. You can access flatpage objects via the
`Django database API`_.
.. _Django model: ../model-api/
.. _django/contrib/flatpages/models.py: http://code.djangoproject.com/browser/django/trunk/django/contrib/flatpages/models.py
.. _Django database API: ../db-api/
Flatpage templates
==================
By default, flatpages are rendered via the template ``flatpages/default.html``,
but you can override that for a particular flatpage.
Creating the ``flatpages/default.html`` template is your responsibility; in
your template directory, just create a ``flatpages`` directory containing a
file ``default.html``.
Flatpage templates are passed a single context variable, ``flatpage``, which is
the flatpage object.
Here's a sample ``flatpages/default.html`` template::
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"
"http://www.w3.org/TR/REC-html40/loose.dtd">
<html>
<head>
<title>{{ flatpage.title }}</title>
</head>
<body>
{{ flatpage.content }}
</body>
</html>
Since you're already entering raw HTML into the admin page for a flatpage,
both ``flatpage.title`` and ``flatpage.content`` are marked as **not**
requiring `automatic HTML escaping`_ in the template.
.. _automatic HTML escaping: ../templates/#automatic-html-escaping