Web sites are normally arranged hierarchically, with certain features common to every page on the site, other features common to certain sections or subsections, and others unique to each page. You can model this easily with a hierarchy of classes, with specific servlets inheriting from their more general superclasses. Again, you can do this two ways, using Cheetah's Containment approach or Inheritance approach.
In the Inheritance approach, parents provide
#blocks and children
override them using
#def. Each child
#extends its immediate
parent. Only the leaf servlets need to be under WebKit's document root
directory. The superclass servlets can live anywhere in the filesystem
that's in the Python path. (You may want to modify your WebKit startup
script to add that library directory to your
PYTHONPATH before starting
Section 17.7 contains information on a stock template that simplifies defining the basic HTML structure of your web page templates.
In the Containment approach, your hierarchy of servlets are not templates, but
each uses one or more templates as it wishes. Children provide callback
methods to to produce the various portions of the page that are their
responsibility, and parents call those methods. Webware's
WebKit.SidebarPage classes operate like this.
Note that the two approaches are not compatible!
WebKit.Page was not
designed to intermix with
Cheetah.Templates.SkeletonPage. Choose either
one or the other, or expect to do some integration work.
If you come up with a different strategy you think is worth noting in this chapter, let us know.