[Mono-list] Mono, ASP.NET et Javascript push

A Rafael D Teixeira rafael.teixeirabr@terra.com.br
Thu, 03 Feb 2005 19:57:59 -0200

On Thu, 2005-02-03 at 19:14, Alain Perry wrote:
> On Thu, 3 Feb 2005 12:51:47 -0800 (PST), Joe Audette
> <joe_audette@yahoo.com> wrote:
> > I don't think you should and probably can't keep a connection alive in a web
> > page. 
> > The web is a stateless environment you request a page, you  get a page,
> > you're done. 
> It indeed is. But the method described (push) enables it to be. It is
> still necessary to send dummy text to keep the connection alive from
> time to time, much like a noop in FTP. But it is possible. An example
> of this is the software that I was using until it became non-free to
> do what my software will do. It was called webmessenger, was written
> in PHP and was using javascript push. I belive you can still try the
> non-free (as in GPL) version for free (as in gratis) at jabbix.com.
> > I would suggest you can make additional requests as needed inside an IFrame
> > so the outer page is not refreshed but the page in the IFrame can carry on a
> > dialog back and forth with the server using multiple requests. 
> This is called polling, and is not an efficient method either. I do
> prefer the push method a lot.

Push is a scalability killer. As ASP.NET and JSP are geared towards
scalability, they don't match well your requirement.

ASP.NET is built upon extensive use of the postback method, what means
that your previous connection will normally get dropped every time the
user click or even type something in the page. 

Polling is much better supported in ASP.NET/JSP. 

If you really really want to cripple your web server (it is even worse
for a server farm, as PUSH connections, will make load balancing
unattainable), I suggest you to develop an asp.net handler (.ASHX) that
is free of the postback paradigm, but I would put it's returns on a
hidden IFRAME anyway, so that you don't have to lose the RAD features of
the .ASPX pages when designing them.

> Thanks anyway,
Rafael "Monoman" Teixeira 
Mono Hacker since 16 Jul 2001 - http://www.go-mono.org/
Mono Brasil Founding Member - http://monobrasil.redesolbrasil.org/
English Blog: http://monoblog.blogspot.com/
Brazilian Portuguese Blog: http://monoblog.weblogger.terra.com.br/