https://blueprints.launchpad.net/swift/+spec/diskfile-databasebroker-as-apis
This work is mostly internal code changes to the organization and structure of swift. There should be no change to the existing behavior. That said, there will be a mechanism to select a plug-able storage back-end, though it is still not clear exactly how that mechanism will work.
Did not make it to rhos-7.0, pushing to rhos‑8.0 review, Sean