Since the annex-tracking-branch is pushed first, git-annex has already
updated the export database when the DATA-PRESENT arrives. Which means
that just using checkPresent is enough to verify that there is some file
on the special remote in the export location for the key.
So, the simplest possible implementation of this happened to work!
(I also tested it with chunked specialremotes, which also works, as long
as the chunk size used is the same as the configured chunk size. In that
case, the lack of a chunk log is not a problem. Doubtful this will ever
make sense to use with a chunked special remote though, that gets pretty
deep into re-implementing git-annex.)
Updated the client side upload tip with a missing step, and reorged for clarity.
Changed the protocol docs because servant parses "true" and "false" for
booleans in query parameters, not "1" and "0".
clientPut with datapresent=True is not used by git-annex, and I don't
anticipate it being used in git-annex, except for testing.
I've tested this by making clientPut be called with datapresent=True and
git-annex copy to a remote succeeds once the object file is first
manually copied to the remote. That would be a good test for the test
suite, but running the http client means exposing it to at least
localhost, and would fail if a real http client was already running on
that port.
optparse-applicative made this hard, the naive implementation this had
before didn't let --hide-missing come after --unlock. And just adding
additional <|> with --hide-missing coming after --unlock didn't work
either. So need to get some options and then combine them.