[Zope] multipart pushing

[Ivan Cornell]

Philippe J wrote:

> > I'd like to implement a chat function using the multipart content type and
> I
> > wonder if that is possible with Zope. My idea is to write a python script
> that
> > pushes the content of a database until e.g. the stop button is pressed in
> the
> > Browser. But how would the script know that it's supposed to stop? And
> would
> > such a longtime connection completely occupy one Zope thread so that I'd
> have
> > to increase the number of threads?
>
> Not sure about the threads, but a quite comonly used trick is to generate
> the html page as the chat evolves, without writting the ending </html> tag.
> The browser will think the connexion is slow, and will continue to display
> the page. You should not, however, use complex layout (tables), as the
> browser sometimes need a complete page to display those.
>

I fairly sure this won't work, as I believe Zope renders a complete page before
sending it the client browser. This is unlike something like PHP which sends
the page as it interprets it.  This confused  me when I first switched as I was
trained to always send headers before any output, however in zope you can
manipulate the REQUEST object right up to the end of your page.

Ivan