Re: [Texmacs-dev] TeXmacs server

[Joris van der Hoeven]

On Mon, Jun 05, 2006 at 05:51:10PM +0200, David MENTRE wrote:
> > 1) A chatting facility, like IRC channels (already implemented,
> >    although a few improvements can still be made).
> > 2) A conferencing utility: an extension of 1 with voice (and maybe video).
> >    This is what would be really useful for me. Currently, it is already
> >    possible to use 1 in combination with Skype (for instance),
> >    but I would like something free and a bit more automatic.
> >    It seems that GNU gatekeepter might help us, but this needs checking.
> 
> In both cases, wouldn't it be more reasonnable to implement those
> functionalities as plugin to existing software, like Ekiga
> (http://www.ekiga.org/) or an IRC client? It took years with many people
> to make those software working, I doubt TeXmacs could do the same.

Just textual chatting is easy to implement and already done.
The more difficult part is voice IP and video conferencing.

> But maybe this is what you want to do after all, Joris, with your
> "TeXmacs server": a kind of component system where one could control the
> TeXmacs core (typesetting and handling of document's parts) from a
> standard interface?

Yes, I do not want to reimplement voice IP and video conferencing.
We should rather search for exsiting software with the following 
characteristics:
  1) The software has no compulsary GUI and can be commanded in the background,
     for instance from the command line over a pipe or socket, or using a 
library.
  2) The software has a protocol such that we can maintain a table with
     user IDs on the TeXmacs server and user ID for the chatting protocol
     of the plug-in. This avoids any unnecessary questions for the user.
  3) For Video applications, it would be nice if they could directly
     display in the TeXmacs window. However, I fear that this is asking
     too much. I investigated this matter for playing videos and no software
     currently allows to do so.

> In that case, which kind of API are you considering?

It is a very easy scheme API. You may declare a new service as follows:

        (request-handler (print-message message)
          (display* "Message: " message "\n")
          #t)

>From the client side you may just do something like

        (send-message server '(print-message "Hallo"))

I already implemented a system to manage user accounts. After logging in,
all communications are secure (well, almost: I am discussing with
a specialist on security issues and I still have to make a few changes).

> Footnotes: 
> [1]  http://www.ietf.org/rfc/rfc1831.txt
> 
> [2]  http://www.beepcore.org/

Thanks for the pointers. In any case, the precise choice is not that important:
at any stage, it is possible to add another protocol as a new service.

What would be a nice contribution from other developers is
to add a facility for voice IP. That should not be hard if
you can find the right software and is a nice exercise.