Implementing userPrefs with common container

["Davies,Douglas" <da...@oclc.org>]

I'm looking into implementing userPrefs with the common container, but
I'm unclear as to what is implemented and what just needs to be
extended.

My first step is to implement set_pref and register it with rpc.  I'm
thinking of implementing this using the appData api (as I've seen other
threads along those lines).  I realize appData needs to be extended to
use a persistent store.  I'm not sure what the default implementation is
using (in memory?).  

I would then think I need to modify the server side to return these
userPrefs (overriding the ones from the gadget spec).  I'm not sure
where to plug into here to use my persistent store.  It seems like the
old container way was for DefaultIframeUriManager to return this when it
created the iframe url.  But I'm not sure that is what common container
is doing.  I think I need to plug into the gadgets.metadata request.

Also it appears that sites like iGoogle provide a user interface from
within the container to set the user prefs.  Is it the containers or the
gadgets responsibility to do this or a little bit of both?  I can see a
horoscope gadget using userPrefs to store a birthdate but not
necessarily have to have a separate settings panel like iGoogle
provides.

Has anyone been through this process that would be willing to share what
they did?  Is this something that the common container will eventually
support out of the box?  How far off base am I with my thinking here?

Thanks,
Doug