.. _topics-install:

=====================
How to install Django
=====================

This document will get you up and running with Django.

Install Python
==============

Being a Python Web framework, Django requires Python.

It works with any Python version 2.3 and higher.

Get Python at http://www.python.org. If you're running Linux or Mac OS X, you
probably already have it installed.

.. admonition:: Django on Jython

    If you use Jython_ (a Python implementation for the Java platform), you'll
    need to follow a few additional steps. See :ref:`howto-jython` for details.

.. _jython: http://jython.org/

Install Apache and mod_python
=============================

If you just want to experiment with Django, skip ahead to the next
section; Django includes a lightweight web server you can use for
testing, so you won't need to set up Apache until you're ready to
deploy Django in production.

If you want to use Django on a production site, use Apache with `mod_python`_.
mod_python is similar to mod_perl -- it embeds Python within Apache and loads
Python code into memory when the server starts. Code stays in memory throughout
the life of an Apache process, which leads to significant performance gains
over other server arrangements. Make sure you have Apache installed, with the
mod_python module activated. Django requires Apache 2.x and mod_python 3.x.

See :ref:`How to use Django with mod_python <howto-deployment-modpython>` for
information on how to configure mod_python once you have it installed.

If you can't use mod_python for some reason, fear not: Django follows the WSGI_
spec, which allows it to run on a variety of server platforms. See the
`server-arrangements wiki page`_ for specific installation instructions for
each platform.

.. _Apache: http://httpd.apache.org/
.. _mod_python: http://www.modpython.org/
.. _WSGI: http://www.python.org/peps/pep-0333.html
.. _server-arrangements wiki page: http://code.djangoproject.com/wiki/ServerArrangements

.. _database-installation:

Get your database running
=========================

If you plan to use Django's database API functionality, you'll need to
make sure a database server is running. Django works with PostgreSQL_,
MySQL_, Oracle_ and SQLite_ (although SQLite doesn't require a separate server
to be running).

Additionally, you'll need to make sure your Python database bindings are
installed.

* If you're using PostgreSQL, you'll need the psycopg_ package. Django supports
  both version 1 and 2. (When you configure Django's database layer, specify
  either ``postgresql`` [for version 1] or ``postgresql_psycopg2`` [for version 2].)

  If you're on Windows, check out the unofficial `compiled Windows version`_.

* If you're using MySQL, you'll need MySQLdb_, version 1.2.1p2 or higher. You
  will also want to read the database-specific notes for the :ref:`MySQL
  backend <ref-databases>`.

* If you're using SQLite and either Python 2.3 or Python 2.4, you'll need
  pysqlite_. Use version 2.0.3 or higher. Python 2.5 ships with an SQLite
  wrapper in the standard library, so you don't need to install anything extra
  in that case.

* If you're using Oracle, you'll need cx_Oracle_, version 4.3.1 or higher. You
  will also want to read the database-specific notes for the :ref:`Oracle
  backend <oracle-notes>`.

If you plan to use Django's ``manage.py syncdb`` command to
automatically create database tables for your models, you'll need to
ensure that Django has permission to create and alter tables in the
database you're using; if you plan to manually create the tables, you
can simply grant Django ``SELECT``, ``INSERT``, ``UPDATE`` and
``DELETE`` permissions. On some databases, Django will need
``ALTER TABLE`` privileges during ``syncdb`` but won't issue
``ALTER TABLE`` statements on a table once ``syncdb`` has created it.

If you're using Django's :ref:`testing framework<topics-testing>` to test database queries,
Django will need permission to create a test database.

.. _PostgreSQL: http://www.postgresql.org/
.. _MySQL: http://www.mysql.com/
.. _Django's ticket system: http://code.djangoproject.com/report/1
.. _psycopg: http://initd.org/tracker/psycopg
.. _compiled Windows version: http://stickpeople.com/projects/python/win-psycopg/
.. _MySQLdb: http://sourceforge.net/projects/mysql-python
.. _SQLite: http://www.sqlite.org/
.. _pysqlite: http://initd.org/tracker/pysqlite
.. _cx_Oracle: http://cx-oracle.sourceforge.net/
.. _Oracle: http://www.oracle.com/

.. _removing-old-versions-of-django:

Remove any old versions of Django
=================================

If you are upgrading your installation of Django from a previous version,
you will need to uninstall the old Django version before installing the
new version.

If you installed Django using ``setup.py install``, uninstalling
is as simple as deleting the ``django`` directory from your Python
``site-packages``.

If you installed Django from a Python egg, remove the Django ``.egg`` file,
and remove the reference to the egg in the file named ``easy-install.pth``.
This file should also be located in your ``site-packages`` directory.

.. admonition:: Where are my ``site-packages`` stored?

    The location of the ``site-packages`` directory depends on the operating
    system, and the location in which Python was installed. To find out your
    system's ``site-packages`` location, execute the following:
    
    .. code-block:: bash

        python -c "from distutils.sysconfig import get_python_lib; print get_python_lib()"

    (Note that this should be run from a shell prompt, not a Python interactive
    prompt.)
    
.. _install-django-code:

Install the Django code
=======================

Installation instructions are slightly different depending on whether you're
installing a distribution-specific package, downloading the latest official
release, or fetching the latest development version.

It's easy, no matter which way you choose.

Installing a distribution-specific package
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Check the :ref:`distribution specific notes <misc-distributions>` to see if your
platform/distribution provides official Django packages/installers.
Distribution-provided packages will typically allow for automatic installation
of dependencies and easy upgrade paths.

.. _installing-official-release:

Installing an official release
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    1. Download the latest release from our `download page`_.

    2. Untar the downloaded file (e.g. ``tar xzvf Django-NNN.tar.gz``,
       where ``NNN`` is the version number of the latest release).
       If you're using Windows, you can download the command-line tool
       bsdtar_ to do this, or you can use a GUI-based tool such as 7-zip_.

    3. Change into the directory created in step 2 (e.g. ``cd Django-NNN``).

    4. If you're using Linux, Mac OS X or some other flavor of Unix, enter
       the command ``sudo python setup.py install`` at the shell prompt.
       If you're using Windows, start up a command shell with administrator
       privileges and run the command ``setup.py install``.

These commands will install Django in your Python installation's
``site-packages`` directory.

.. _bsdtar: http://gnuwin32.sourceforge.net/packages/bsdtar.htm
.. _7-zip: http://www.7-zip.org/

.. _installing-development-version:

Installing the development version
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

.. admonition:: Tracking Django development
    
    If you decide to use the latest development version of Django,
    you'll want to pay close attention to `the development timeline`_,
    and you'll want to keep an eye on `the list of
    backwards-incompatible changes`_. This will help you stay on top
    of any new features you might want to use, as well as any changes
    you'll need to make to your code when updating your copy of Django.
    (For stable releases, any necessary changes are documented in the
    release notes.)

.. _the development timeline: http://code.djangoproject.com/timeline
.. _the list of backwards-incompatible changes: http://code.djangoproject.com/wiki/BackwardsIncompatibleChanges

If you'd like to be able to update your Django code occasionally with the
latest bug fixes and improvements, follow these instructions:

1. Make sure that you have Subversion_ installed, and that you can run its
   commands from a shell. (Enter ``svn help`` at a shell prompt to test
   this.)

2. Check out Django's main development branch (the 'trunk') like so:

   .. code-block:: bash

       svn co http://code.djangoproject.com/svn/django/trunk/ django-trunk

3. Next, make sure that the Python interpreter can load Django's code. There
   are various ways of accomplishing this.  One of the most convenient, on
   Linux, Mac OSX or other Unix-like systems, is to use a symbolic link:
   
   .. code-block:: bash

       ln -s `pwd`/django-trunk/django SITE-PACKAGES-DIR/django

   (In the above line, change ``SITE-PACKAGES-DIR`` to match the location of
   your system's ``site-packages`` directory, as explained in the
   "Where are my ``site-packages`` stored?" section above.)

   Alternatively, you can define your ``PYTHONPATH`` environment variable
   so that it includes the ``django-trunk`` directory. This is perhaps the
   most convenient solution on Windows systems, which don't support symbolic
   links. (Environment variables can be defined on Windows systems `from the
   Control Panel`_.)

   .. admonition:: What about Apache and mod_python?

      If you take the approach of setting ``PYTHONPATH``, you'll need to
      remember to do the same thing in your Apache configuration once you
      deploy your production site. Do this by setting ``PythonPath`` in your
      Apache configuration file.

      More information about deployment is available, of course, in our
      :ref:`How to use Django with mod_python <howto-deployment-modpython>`
      documentation.

4. On Unix-like systems, create a symbolic link to the file
   ``django-trunk/django/bin/django-admin.py`` in a directory on your system
   path, such as ``/usr/local/bin``. For example:
   
   .. code-block:: bash

       ln -s `pwd`/django-trunk/django/bin/django-admin.py /usr/local/bin

   This simply lets you type ``django-admin.py`` from within any directory,
   rather than having to qualify the command with the full path to the file.

   On Windows systems, the same result can be achieved by copying the file
   ``django-trunk/django/bin/django-admin.py`` to somewhere on your system
   path, for example ``C:\Python24\Scripts``.

You *don't* have to run ``python setup.py install``, because you've already
carried out the equivalent actions in steps 3 and 4.

When you want to update your copy of the Django source code, just run the
command ``svn update`` from within the ``django-trunk`` directory. When you do
this, Subversion will automatically download any changes.

.. _`download page`: http://www.djangoproject.com/download/
.. _Subversion: http://subversion.tigris.org/
.. _from the Control Panel: http://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/sysdm_advancd_environmnt_addchange_variable.mspx
