This tutorial begins where Tutorial 5 left off. We’ve built a tested Web-poll application, and we’ll now add a stylesheet and an image.
Aside from the HTML generated by the server, web applications generally need to serve additional files — such as images, JavaScript, or CSS — necessary to render the complete web page. In Django, we refer to these files as “static files”.
For small projects, this isn’t a big deal, because you can just keep the static files somewhere your web server can find it. However, in bigger projects – especially those comprised of multiple apps – dealing with the multiple sets of static files provided by each application starts to get tricky.
That’s what django.contrib.staticfiles is for: it collects static files
from each of your applications (and any other places you specify) into a
single location that can easily be served in production.
First, create a directory called static in your polls directory. Django
will look for static files there, similarly to how Django finds templates
inside polls/templates/.
Django’s STATICFILES_FINDERS setting contains a list
of finders that know how to discover static files from various
sources. One of the defaults is AppDirectoriesFinder which
looks for a “static” subdirectory in each of the
INSTALLED_APPS, like the one in polls we just created. The admin
site uses the same directory structure for its static files.
Within the static directory you have just created, create another directory
called polls and within that create a file called style.css. In other
words, your stylesheet should be at polls/static/polls/style.css. Because
of how the AppDirectoriesFinder staticfile finder works, you can refer to
this static file in Django simply as polls/style.css, similar to how you
reference the path for templates.
Static file namespacing
Just like templates, we might be able to get away with putting our static
files directly in polls/static (rather than creating another polls
subdirectory), but it would actually be a bad idea. Django will choose the
first static file it finds whose name matches, and if you had a static file
with the same name in a different application, Django would be unable to
distinguish between them. We need to be able to point Django at the right
one, and the easiest way to ensure this is by namespacing them. That is,
by putting those static files inside another directory named for the
application itself.
Put the following code in that stylesheet (polls/static/polls/style.css):
li a {
color: green;
}
Next, add the following at the top of polls/templates/polls/index.html:
{% load static %}
<link rel="stylesheet" type="text/css" href="{% static 'polls/style.css' %}">
The {% static %} template tag generates the absolute URL of static files.
That’s all you need to do for development.
Start the server (or restart it if it’s already running):
$ python manage.py runserver
...\> py manage.py runserver
Reload http://localhost:8000/polls/ and you should see that the question
links are green (Django style!) which means that your stylesheet was properly
loaded.
Next, we’ll create a subdirectory for images. Create an images subdirectory
in the polls/static/polls/ directory. Inside this directory, put an image
called background.gif. In other words, put your image in
polls/static/polls/images/background.gif.
Then, add to your stylesheet (polls/static/polls/style.css):
body {
background: white url("images/background.gif") no-repeat;
}
Reload http://localhost:8000/polls/ and you should see the background
loaded in the top left of the screen.
Warning
Of course the {% static %} template tag is not available for use in
static files like your stylesheet which aren’t generated by Django. You
should always use relative paths to link your static files between each
other, because then you can change STATIC_URL (used by the
static template tag to generate its URLs) without having to modify
a bunch of paths in your static files as well.
These are the basics. For more details on settings and other bits included with the framework see the static files howto and the staticfiles reference. Deploying static files discusses how to use static files on a real server.
When you’re comfortable with the static files, read part 7 of this tutorial to learn how to customize Django’s automatically-generated admin site.
Oct 31, 2018