[mod_python] Pre and postprocess blocks (Publisher mode)?

Hi!

Graham Dumpleton wrote:
>> Because the controllers are python modules, it is avoid the "same module
>> name" hell (in another modules I can use same name - example index).
>
> What exactly are you talking about when you say 'same module name hell'?
The basic python import problem - example: more index.py.
>
> module reloading. See the apache.import_module() function described
> in:
>
>  http://www.modpython.org/live/current/doc-html/pyapi-apmeth.html
Yes, I know it, and now I use it (3.3.1).
>
>> I know that modpy supports publisher mode, that same like pylons'
>> working method.
>>
>> 1.)
>> But I want to know: how the modpython helps me to I do pre- and
>> postprocess operations?
>
> Apache/mod_python actually has a much better developed concept of
> request processing phases than Pylons and other monolithic solutions
> such as Django. Have a look at the section '4.4.4 Process HTTP
> Request' in:
>
>  http://www.fmc-modeling.org/projects/apache/html/4_4Request_Response_Loop.html 
>
It is too complicated for me to understand these process-diagrams of apache.
> A post handler or cleanup handler can be registered using the
> req.register_cleanup() method. See documentation in:
>
>  http://www.modpython.org/live/current/doc-html/pyapi-mprequest-meth.html
> So, read through all those references and try and take it in. Then
> perhaps come back with more specific questions with examples of what
> you have tried.

I simplify my question:.
I want to use only two callback functions: the first named "pre" must 
called by apache *before* the calling of published procedure, and the 
second (named "post") must called by apache *after* the calling of 
published procedure.

So the question is that: can I set these two callback functions in the 
PUBLISHER HANDLER to initialize and finalize the request handling?
Like in pylons?

In pylons the controllers have _before_ and _after_ methods, they are 
called before/after the calling of the action method.
Example:
.... XController:
  def __before__(self):
       OpenSession()
       OpenDB()
       CheckLogin()
   def __after__(sefl):
       SaveSession()

   def  index(self):
        return Response('INDEX!')

How to I use same mechanism in modpy3.3.1?

Like this pseudocode:

<Directory ...>
   AddHandler publisher prefunctionname Pre postfunctionname Post
...

Thanks for your help:
  dd