web interface

[Tom Anderson]

On Mon, 7 Nov 2005, Ajar wrote:

> I have a stand alone application which does some scientific 
> computations. I want to provide a web interface for this app. The app is 
> computationally intensive and may take long time for running. Can 
> someone suggest me a starting point for me? (like pointers to the issues 
> involved in this,

You're probably best off starting a new process or thread for the 
long-running task, and having the web interface return to the user right 
after starting it; you can then provide a second page on the web interface 
where the user can poll for completion of the task, and get the results if 
it's finished. You can simulate the feel of a desktop application to some 
extent by having the output of the starter page redirect the user to the 
poller page, and having the poller page refresh itself periodically.

What you really want is a 'push' mechanism, by which the web app can 
notify the browser when the task is done, but, despite what everyone was 
saying back in '97, we don't really have anything like that.

> or even better any of the existing tools for doing this...)

Pise does what you want, and much more:

http://www.pasteur.fr/recherche/unites/sis/Pise/

But i have no idea if it's of any use to you - it was designed for 
bioinformatics programs, and might not be easily adaptable to other tasks.

Old-enough-to-remember-the-push-hype-ly y'rs,
tom

-- 
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