Upgrading to Django 1.6
#######################

:date: 2013-12-29 18:00
:tags: Django
:slug: upgrading-to-django-1.6
:author: Brian Neal
:summary: `Django`_ 1.6 came out recently, which was soon followed by 1.6.1, and it looks like 1.6.2 is on the way. I finally got around to upgrading two of my largest sites. I thought I would make a list of what I changed at a high level for my own reference. Perhaps someone else may find it useful as well.

Getting started
===============

`Django`_ 1.6 came out recently, which was soon followed by 1.6.1, and it looks
like 1.6.2 is on the way. I finally got around to upgrading two of my largest
sites. I thought I would make a list of what I changed at a high level for my
own reference. Perhaps someone else may find it useful as well.

In any event, I highly recommend you read the excellent `release notes`_ and
`deprecation timeline`_. The changes in 1.6 didn't seem groundbreaking, but
they were numerous. I spent a lot of time reading through the notes and trying
to decide if the issues affected me or not.

I recommend you run with warnings turned on::

   $ python -Wall manage.py runserver

This will help you flag down issues in your code. If you aren't sure where
a warning is coming from, you can turn warnings into exceptions and get
a traceback (see the Python docs on the warnings_ library). Another trick is to
put a pdb_ breakpoint in the Django code before or after the warning, then you
can examine the call stack with the ``w`` command.

Upgrade Issues
==============

Here are the issues that I ran into. Of course you may have a very different
experience depending on what features of Django you used and the details of
your site.

#. The location of the ``XViewMiddleware`` changed. I had to update my
   ``MIDDLEWARE_CLASSES`` setting as a result. 
#. Various ``get_query_set`` to ``get_queryset`` changes. The Django developers
   have ironed out some naming inconsistencies in method names on both model
   managers and ``ModelAdmin`` classes. 
#. In template / form processing, the ``label_tag`` now includes the
   ``label_suffix``. I noticed this when I saw that I had two colons on a form
   field's label.
#. One very nice change that I am please to see is that Django now does test
   discovery just like the unittest_ module in the standard library. To take
   advantage of this I renamed all my test modules from ``view_tests.py`` to
   ``test_views.py``, for example. This also let me get rid of ``import``
   statements in various ``__init__.py`` files in test subdirectories. In other
   words, you no longer have to have silly lines like
   ``from view_tests import *`` in your test packages' ``__init__.py`` files.
#. Django now supports database connection persistence. To take advantage of
   this you need to set the CONN_MAX_AGE_ setting to a non-zero value.
#. The ``CACHE_MIDDLEWARE_ANONYMOUS_ONLY`` setting is now deprecated and can be
   removed. For various reasons explained in the notes this never really worked
   right anyway.
#. Updated to version 1.0 of the django-debug-toolbar_. The version I was using
   would not work in Django 1.6. It is so good to see that this project is
   being actively maintained again. There are several new panels and neat
   features, check it out!
#. You now get a warning if you have a ``ModelForm`` without an ``exclude`` or
   ``fields`` meta option. This is rather nice as I have been bit by this in
   the past when a form suddenly started showing a newly added field that it
   should not have. I added a ``fields`` option to a ``ModelForm`` as a result.
   Unfortunately some third party applications I am using have this problem as
   well.
#. The ``cycle`` tag has new XSS_ protection. To make use of it now, you have
   to add a ``{% load cycle from future %}`` tag into your templates.
#. The ``django.contrib.auth`` password reset function is now using base 64 encoding of the
   ``User`` primary key. The details are `here <https://docs.djangoproject.com/en/1.6/releases/1.6/#django-contrib-auth-password-reset-uses-base-64-encoding-of-user-pk>`_. This affected me 
   because I am using a custom password reset URL, and thus I needed to update
   my URL pattern for both the new parameter name and the regular expression
   for base 64. I missed this originally and I started getting 404's on my
   password reset confirmation URLs. And yes, this is something I should have a
   test for!

What I didn't do
================

Many of the warnings that I got came from third party modules that I have not
updated in a long time, including Celery_ and Haystack_. I am going to have to
schedule some time to update to the latest versions of these apps. Hopefully
the warnings will be fixed in the newer versions, but if not I can write
tickets or possibly submit patches / pull requests. This is the price of
progress I suppose.

I also use a couple of smaller third party applications that seem to be no
longer maintained. These apps are now generating some warnings. I'll have to
fork them and fix these myself. Luckily these projects are on GitHub so this
should not be a problem.

Finally I am still facing the problem of what to do about the deprecation of
the ``AUTH_PROFILE_MODULE`` and the ``get_profile`` method. This will be
removed in Django 1.7. I've been doing some more reading about this and I'm
less scared about this than I used to. I'll probably just change my profile
model to have a one-to-one relationship with the provided ``User`` model. I'll
have to do some more researching and thinking about this before Django 1.7.


Conclusion
==========

Once again the upgrade process went smoother and quicker than I thought thanks
to the excellent release notes and the Django team's use of Python warnings to
flag deprecated features.


.. _Django: https://www.djangoproject.com/
.. _release notes: https://docs.djangoproject.com/en/1.6/releases/1.6/
.. _deprecation timeline: https://docs.djangoproject.com/en/1.6/internals/deprecation/
.. _warnings: http://docs.python.org/library/warnings.html
.. _pdb: http://docs.python.org/library/pdb.html
.. _unittest: http://docs.python.org/2/library/unittest.html
.. _CONN_MAX_AGE: https://docs.djangoproject.com/en/1.6/ref/settings/#conn-max-age
.. _XSS: http://en.wikipedia.org/wiki/Cross-site_scripting
.. _configurable user model: https://docs.djangoproject.com/en/1.5/topics/auth/customizing/#auth-custom-user
.. _django-debug-toolbar: https://pypi.python.org/pypi/django-debug-toolbar
.. _Celery: http://www.celeryproject.org/
.. _Haystack: http://haystacksearch.org/