Session CGI!

[Harry George]

Erno Kuusela <erno-news at erno.iki.fi> writes:

> johng2001 at rediffmail.com (John) writes:
> 
> > > You could use cookies and/or database writes.
> > 
> > Sadly that is what I want to avoid :-(
> 
> see here: http://www.catdancers.com/webmags/webtech/1998/03/perl/
> 
> it's about perl, but you can apply the idea to python too.
> 
>   -- erno


There are two problems:

1. Where to store state.  Databases, cookies, and pickle files are
   available.  I've used pickle files for low volume apps.

2. How to structure the CGI code.  Of course, something like webware
   or twisted would hide it all, but let's assume you are writing from
   scratch.  Since this is a stateless protocol, we can borrow from
   another (and solved) stateless protocol -- sockets.

   So for each webpage,we make 2 functions (or methods): send_xyz and
   recv_xyz.  On wakeup,we check a hidden field to determine which
   "xyz" is arriving, and call its recv.  There we use another hidden
   field (or an SSL tag) to get the right database or pickle data and
   load it into an object.  Continue processing as if there was no
   time gap.  At end (ready for more user input), call the proper
   "send".  It prepares the hidden fields, saves the state, and prints
   the outgoing page.  The script exits and we are back at the
   browser.

-- 
harry.g.george at boeing.com
6-6M21 BCA CompArch Design Engineering
Phone: (425) 342-0007