Web Application - User Management - RBAC

[Martin]

I am putting together a simple web-app for construction of standard documents.
Basically the app will present a form for inputting the variable content /
overriding standard text and send back a complete .doc / .swx. The motivation
for using a web app instead of templates is that I have found templates too
brittle, and I would like to store the variable/overriding data in an SQL 
backend.

I would like to implement RBAC(Role Based Access Control) in the app. How would
one best go about that ? is there any code available(classes/frameworks) ? would
one render pages and thereby options based on role or guard methods(i.e. call
some kind of access control object and raise exceptions if an action is not
allowed for the role, or perhaps derive all objects from an object that
automatically handles such checks when a method is called ?) or some other
approach ? I have looked at Webwares UserKit but it is apparently incomplete and
frankly I can't figure out how it works.

I am planning to use CherryPy as a framework, but would be open to another 
approach.

Regards,

Martin