Comment 1 for bug 1745245

For replicated objects this isn't currently easy to solve. For EC and encryption the MIME/chunked packing protocol supports the proxy sending metadata after the object body which the object-server should consider before the finalize.

Moving forward with https://review.openstack.org/#/c/427911/ may offer a framework by which we can have a common pattern between unencrypted replicated and other storage formats that allows us to always send a proxy computed etag behind a object PUT.