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I have updated the old oslo.config drivers spec [1] to remove a bunch of
the information about etcd and focus on the secret store use case we
discussed at the PTG in queens. I think this work is a prerequisite for
the plaintext secrets spec [2] work, because castellan already depends
on oslo.config so we can't have oslo.config invoke castellan directly.

As it stands, the spec itself probably needs some more work.  I can
assist with the design, implementation advice, and code reviews,
but I don't expect to have time to do the implementation work myself
this cycle. If you are interested in helping, please leave a comment
on the review [1].

Doug

[1] https://review.openstack.org/#/c/454897
[2] https://review.openstack.org/#/c/474304