Re: system Desktop notifications

[Zbigniew Jędrzejewski-Szmek <zbyszek in waw pl>]

On Mon, Jun 23, 2014 at 11:10:14PM +0200, Rolf Fokkens wrote:
> Thanks for the feedback. I can understand that it may not always be
> helpful indeed.
>
> Let me refrase my question: Wouldn't it be useful that some system
> related messages (backups, SMART...) are presented to "whom it
> concerns"? The users whom it conserns could be:
>
> - The (workstation) owner. So most likely the graphical console, the
> local X server should present the messages. And maybe even when no
> user is logged on, so a message popup on top of the login screen?
> Could be helpful.
> - The sysadmin. That might be whoever is in the wheel group. And it
> doesn't matter if he's working remote or local;
> - Subscribers? Maybe users should be able to subscribe to this kind
> of information.
>
> It's like when working in character mode: kernel messages show up on
> (local) consoles. With wall it's possible (for the sysadmin) to
> write a message to all users (who allow this). Something like that,
> but then in the wordt of graphical consoles. I think this might be
> useful in general, and maybe for backups in particular.
>
> I was thinking about (system) dbus as the solution: the session
> manager, the (local?) login screen or the notifier deamon can
> subscribe to a notification service on the system dbus.
>
> But considering dbus may have been wrong. Maybe there are good
> alternatives, suggestions are welcome.
Dbus would be equivalent to a "push mode". Users watching the journal
(and e.g. having notifications pop up in their graphical environment)
is a "pull mode". Both have merits, but "pull mode" is almost
there. One of the advantages is that the privilege separation is
working already by adding the users who are allowed to view logs to adm
group, and/or settings facls on /var/log/journal/.
This would update the classical "log messages of critical priority"
to all logged in users for the modern era of graphical desktops.
I'm pretty sure that using Gnome Logs source as a basis of a
simple applet which pops up notifications is doable.

Zbyszek