Comment 4 for bug 806098

Excerpts from Gustavo Niemeyer's message of Tue Jul 05 19:34:48 UTC 2011:
> It's still not entirely clear what you're looking for. You're using
> facters for what, more precisely, and how's that connected with
> relationships?
>
> relation-set is specific to the relation being changed, so it's impossible to have it during the install hook,
> because there are no relations established at this point.
>

It sounds like this bug is really about unit private data. Effectively a place to stash runtime information in zk across hooks. What we've discussed before in this context is hooks are free to store data locally on disk in whatever format is convienent. Our zookeeper storage is really specific to coordination cases, which span cross machine communication. All that said, i think it might be fine to establish some sort of k/v store and cli api for the unit against say a sqlite db.