=========
Rationale
=========

As of early 2011, there is a lot of flux in the Python world with
regard to web frameworks. There are a couple of big players, namely
`Django`_, `Pylons`_, and `TurboGears`_, as well as several more
obscure projects like `CherryPy`_ and `Bottle`_. Having worked with
many of these projects, I decided that although each has its strengths,
they all also had something about them that just made me feel
uncomfortable working with them.

Framework Comparison
====================

Django
++++++

.. rubric:: Strengths

* Very popular and actively developed, making it easy to get help and
  solve problems
* Fully-featured, including an Object-Relational Mapper, URL dispatcher,
  template engine, and form library. Also includes "goodies" like
  authentication, an "admin" application, and sessions

.. rubric:: Discomforts

I am not specifically listing any of these issues as weaknesses or
drawbacks, because they aren't *per-se*. Honestly, there isn't anything
wrong with Django, and many people love it. Personally, I don't feel
comfortable working with it for a few reasons.

* Storing configuration in a Python module is absurd
* All of the components are so tightly-integrated it is nearly
  impossible to use some pieces without the others.
  
  * I really don't like its ORM. `SQLAlchemy`_ is tremendously more
    powerful, and isn't nearly as restrictive (naming conventions, etc.)
  * The session handling middleware is very limited in comparison to
    other projects like `Beaker`_
  * I am not fond of the template engine and would prefer to use
    `Genshi`_.

Pylons/Pyramid
++++++++++++++

The original Pylons was a very powerful web framework. It was probably
my favorite framework, and I have built a number of applications using
it. Unfortunately, development has been discontinued and efforts are
now being concentrated on `Pyramid`_ instead.

Pylons
------

.. rubric:: Strengths

* While not as popular as Django, there still a significant following
* The  code base is very decoupled, allowing developers to swap out
  components without affecting the overall functionality of the
  framework.

.. rubric:: Weaknesses

* Overutilization of StackedObject proxies and global variables

Pyramid
-------

I simply do not like Pyramid at all, and it is really disappointing that
the Pylons project has moved in this direction. Essentially everything
that I liked about Pylons is gone. The idea of using *traversal* to map
URLs to routines is clever, but it is overly complex compared to the
familiar URL dispatching in other frameworks. 

* Tightly integrated with several Zope components, mostly interfaces
  (*puke*)
* Template renderers are insanely complex and again, I don't like Zope
  interfaces. There is no simple way to use Genshi, which I absolutely
  adore.


Other Frameworks
++++++++++++++++

I haven't used the other frameworks as much. In general, I try to avoid
having my applications depend on obscure or unmaintained libraries
because when I find a bug (and I will), I need some assurance that it
will be fixed soon. I do not like having to patch other people's code
in production environments, especially if it is an application I am 
passing along to a client.

I never really looked at TurboGears at all, and with the recent changes
to the Pylons project, upon which TurboGears is based, there is a great
deal of uncertainty with regard to its future.

CherryPy is very nice, and I did a bit of work with it a while back. I
thought it was dead for a long time, though, and I have never really
produced a production application built on it. With its most recent
release (3.2.0), it is the first web framework to support Python 3,
which is exciting. I may revisit it in the near future, as a matter
of fact.

The Truth
=========

The truth is, I started *Milla* as an exercise to better understand
WSGI. All of the frameworks discussed above are great, and will most
likely serve everyone's needs. There really isn't any reason for anyone
to use *Milla* over any of them, but I won't stop you.

.. _Django: http://www.djangoproject.com/
.. _Pylons: http://pylonshq.com/
.. _TurboGears: http://www.turbogears.org/
.. _CherryPy: http://www.cherrypy.org/
.. _Bottle: http://bottlepy.org/
.. _SQLAlchemy: http://www.sqlalchemy.org/
.. _Beaker: http://beaker.groovie.org/
.. _Genshi: http://genshi.edgewall.org/
.. _Pyramid: http://docs.pylonsproject.org/projects/pyramid/1.0/index.html