[PATCH 2/2] Added SQLite history plugin

[Denis Kenzior]

Hi Niko,
Hi Niko,
> After sending X messages the app goes down for some reason, when comes
> up again there are Y messages in the history plugin becouse Y-X new
> messages arrived.
> 
> Well, I want my app to be able to recover from the downtime using the
> history plugin, and want to avoid to resend the first X messages.
> 
> A simple way to achieve that is adding the id in the IncomingMessage
> signal, so the app is able to store it somewhere every time it
> receives a new message.

I suggest storing this information directly in the history database.  E.g. 
Read / Unread flag.  Ideally the application can access the database 
concurrently to mark the message as Read / Unread.  If not, then some sort of 
DBus API will be required.

> 
> When the app start, it simply query the history plugin and start
> processing only messages where id > lastsavedid.

Why not query the database directly?

Regards,
-Denis