MVC-type Framework in Python

[Andreas Pauley]

Hi,

I'm interested in finding a nice way to develop applications that have
their business logic separated from the user interface (among other
things). This should enable easier maintenance, more flexibility and
(ideally) less development time for the app.

I've recently read about the Model-View-Controller design framework
(originally used in SmallTalk applications, or so it seems).
What python-specific tools/frameworks would you recommend that can be used
to implement MVC, or something similar (or perhaps better) than MVC?

I'm looking for something that can help build
interface-independent applications, with all logic in a central place.
There would typically be a GUI interface, character interface and
web-based interface, all accessing the same python logic.
The interfaces need not be python-specific. I would like, for example, to
have an existing PHP website access the same logic.

Another thing that would be nice is centralized validation.
If you change your validation rules in one place, the interfaces get to
know that without you having to change code on the interface.
Is it feasible to have python extract validation rules from the database
(e.g. a varchar(20) field) and pass that through to a gui interface that
would limit the amount of characters entered to 20? If you then change the
database field to a varchar(30), the change should be
detected without having to change any other code.

At the moment I'm just researching all of the different options for
designing/implementing applications (typically multi-user database-driven
apps), so I would appreciate any ideas. I assume some ideas have proven
themselves more feasible in production environments than others.

Regards,
Andreas.