The Django Book

Installing an Official Release

Most people will want to install the latest official release from http://www.djangoproject.com/download/. Django uses the standard Python distutils installation method, which in Linux land looks like this:

1. Download the tarball, which will be named something like Django-0.96.tar.gz.
2. tar xzvf Django-*.tar.gz.
3. cd Django-*.
4. sudo python setup.py install.

On Windows, we recommend using 7-Zip to handle all manner of compressed files, including .tar.gz. You can download 7-Zip from http://www.djangoproject.com/r/7zip/.

Change into some other directory and start python. If everything worked, you should be able to import the module django:

>>> import django
>>> django.VERSION
(0, 96, None)

Installing Django from Subversion

If you want to work on the bleeding edge, or if you want to contribute code to Django itself, you should install Django from its Subversion repository.

Subversion is a free, open source revision-control system similar to CVS, and the Django team uses it to manage changes to the Django codebase. You can use a Subversion client to grab the very latest Django source code and, at any given time, you can update your local version of the Django code, known as your local checkout, to get the latest changes and improvements made by Django developers.

The latest and greatest Django development code is referred to as the trunk. The Django team runs production sites on trunk and strives to keep it stable.

To grab the latest Django trunk, follow these steps:

1. Make sure you have a Subversion client installed. You can get the software free from http://subversion.tigris.org/, and you can find excellent documentation at http://svnbook.red-bean.com/.
2. Check out the trunk using the command svn co http://code.djangoproject.com/svn/django/trunk djtrunk.
3. Create site-packages/django.pth and add the djtrunk directory to it, or update your PYTHONPATH to point to djtrunk.
4. Place djtrunk/django/bin on your system PATH. This directory includes management utilities such as django-admin.py.

After downloading from Subversion and following the preceding steps, there’s no need to python setup.py install—you’ve just done the work by hand!

Because the Django trunk changes often with bug fixes and feature additions, you’ll probably want to update it every once in a while — or hourly, if you’re really obsessed. To update the code, just run the command svn update from within the djtrunk directory. When you run that command, Subversion will contact http://code.djangoproject.com, determine if any code has changed, and update your local version of the code with any changes that have been made since you last updated. It’s quite slick.

Using Django with PostgreSQL

If you’re using PostgreSQL, you’ll need the psycopg package available from http://www.djangoproject.com/r/python-pgsql/. Take note of whether you’re using version 1 or 2; you’ll need this information later.

If you’re using PostgreSQL on Windows, you can find precompiled binaries of psycopg at http://www.djangoproject.com/r/python-pgsql/windows/.

Using Django with SQLite 3

If you’re using a Python version over 2.5, you already have SQLite. If you’re working with Python 2.4 or older, you’ll need SQLite 3— not version 2—from http://www.djangoproject.com/r/sqlite/ and the pysqlite package from http://www.djangoproject.com/r/python-sqlite/. Make sure you have pysqlite version 2.0.3 or higher.

On Windows, you can skip installing the separate SQLite binaries, since they’re statically linked into the pysqlite binaries.

Using Django with MySQL

Django requires MySQL 4.0 or above; the 3.x versions don’t support nested subqueries and some other fairly standard SQL statements. You’ll also need the MySQLdb package from http://www.djangoproject.com/r/python-mysql/.

Using Django Without a Database

As mentioned earlier, Django doesn’t actually require a database. If you just want to use it to serve dynamic pages that don’t hit a database, that’s perfectly fine.

With that said, bear in mind that some of the extra tools bundled with Django do require a database, so if you choose not to use a database, you’ll miss out on those features. (We highlight these features throughout this book.)

The Development Server

Django includes a built-in, lightweight Web server you can use while developing your site. We’ve included this server so you can develop your site rapidly, without having to deal with configuring your production Web server (e.g., Apache) until you’re ready for production. This development server watches your code for changes and automatically reloads, helping you make many rapid changes to your project without needing to restart anything.

Change into the mysite directory, if you haven’t already, and run the command python manage.py runserver. You’ll see something like this:

Validating models...
0 errors found.

Django version 1.0, using settings 'mysite.settings'
Development server is running at http://127.0.0.1:8000/
Quit the server with CONTROL-C.

Although the development server is extremely nice for, well, development, resist the temptation to use this server in anything resembling a production environment. The development server can handle only a single request at a time reliably, and it has not gone through a security audit of any sort. When the time comes to launch your site, see Chapter 20 for information on how to deploy Django.

python manage.py runserver 8080

python manage.py runserver 0.0.0.0:8080

Now that the server’s running, visit http://127.0.0.1:8000/ with your Web browser. You’ll see a “Welcome to Django” page shaded a pleasant pastel blue. It worked!