Re: Lisp Web Development and Application State




mrcsparker@xxxxxxxxx wrote:
Pierre THIERRY wrote:
Le Sat, 02 Sep 2006 20:51:00 -0700, mrcsparker@xxxxxxxxx a écrit :
So, how would you build a simple web application that saves state
between pages in Lisp?

With a running Lisp image instead of scripts run by the Web server, part
of the problem just vanishes. In my case, I added Elephant so that I can
just consider my data persistent, even accross reboots of the image.

Partly,
Nowhere man
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OpenPGP 0xD9D50D8A

How do you know when to let go of the user data? For example, if a
user starts to fill out a multi-page form and never finishes, how long
do you keep the data on the server?

The most straightforward solution is probably using timeout to reap old
continuations. Elephant is an object store, it persists arbitrary lisp
data
by writing to a Berkeley DB.

Incidentally, my google Summer of Code project might interest you.
http://common-lisp.net/project/wispylisp/tutorial.html
It has continuation enabled form, which lets you program functionally
across the server/client barrier.

.