Help designing DBus API

[Arvin Schnell]

Hi,

I could use some advice designing a DBus API for snapper, a tool
to manage filesystem snapshots (e.g. btrfs). One method call in
the snapper library makes me wonder what an appropriate DBus API
should look like.

The method call can take very long, e.g. several minutes. It has
callbacks to 1. give feedback (which file is currently restored)
and 2. report errors (some file could not be restored). In the
future the error callback might also give to user the choice to
continue or abort.

AFAIS DBus does not offer callbacks. It offers signals but those
are sent to every client and naturally cannot return anything.

What is the best way to call this method via DBus?

Thanks in advance, Arvin

PS: I couldn't find a comprehensive document about designing a
    DBus API. Is anything like that available?

-- 
Arvin Schnell, <aschnell at suse.de>
Senior Software Engineer, Research & Development
SUSE LINUX Products GmbH, GF: Jeff Hawn, Jennifer Guild, Felix Imendörffer, HRB 16746 (AG Nürnberg)
Maxfeldstraße 5
90409 Nürnberg
Germany