Since an external process can be in the middle of some operation when an
async exception is received, it has to be shut down then. Using
cleanupProcess will close its IO handles and send it a SIGTERM.
If a special remote choses to catch SIGTERM, it's fine for it to do some
cleanup then, but until it finishes, git-annex will be blocked waiting
for it. If a special remote blocked SIGTERM, it would cause a hang.
Mentioned in docs.
Also, in passing, fixed a FD leak, it was not closing the error handle
when shutting down the external. In practice that didn't matter before because
it was only run when git-annex was itself shutting down, but now that it
can run on exception, it would have been a problem.
Apparently some externals use GETCONFIG name, and the documentation as
written can be read to allow it, although IIRC it was not really my
intent to. If someone does do this, they should not include it in
LISTCONFIGS, since git-annex already tracks its own config settings.
Special remote programs that use GETCONFIG/SETCONFIG are recommended
to implement it.
The description is not yet used, but will be useful later when adding a way
to make initremote list all accepted configs.
configParser now takes a RemoteConfig parameter. Normally, that's not
needed, because configParser returns a parter, it does not parse it
itself. But, it's needed to look at externaltype and work out what
external remote program to run for LISTCONFIGS.
Note that, while externalUUID is changed to a Maybe UUID, checkExportSupported
used to use NoUUID. The code that now checks for Nothing used to behave
in some undefined way if the external program made requests that
triggered it.
Also, note that in externalSetup, once it generates external,
it parses the RemoteConfig strictly. That generates a
ParsedRemoteConfig, which is thrown away. The reason it's ok to throw
that away, is that, if the strict parse succeeded, the result must be
the same as the earlier, lenient parse.
initremote of an external special remote now runs the program three
times. First for LISTCONFIGS, then EXPORTSUPPORTED, and again
LISTCONFIGS+INITREMOTE. It would not be hard to eliminate at least
one of those, and it should be possible to only run the program once.
Made responses to git-annex requests be listed under each request.
This did lead to a little duplication since some replies are used for 2
requests, but it also makes it much clearer and easier to see how the
protocol works.
And, it makes each request self-contained, so they can be split out into
separate pages.
Avoid a warning message when renameExport is not supported, and just
fallback to deleting with a subsequent re-upload. Especially needed for
importtree remotes, where renameExport needs to be disabled.
This changes the external special remote protocol, but in a
backwards-compatible way. A reply of UNSUPPORTED-REQUEST to an older
version of git-annex will cause it to make renameExport return False.
Had to add two more API calls to override export APIs that are not safe
for use in combination with import.
It's unfortunate that removeExportDirectory is documented to be allowed
to remove non-empty directories. I'm not entirely sure why it's that
way, my best guess is it was intended to make it easy to implement with
just rm -rf.
External special remotes can now add info to `git annex info $remote`, by
replying to the GETINFO message.
Had to generalize some helpers to allow consuming multiple messages from
the remote.
The code added to Remote/* here is AGPL licensed, thus changed the license
of the files.
This commit was sponsored by Jake Vosloo on Patreon.
Allows using new special remote messages when git-annex supports them,
and avoiding using them when git-annex is too old. The new INFO is one
such message.
There's also the possibility, currently unused, for the special remote's
reply to include some kind of extensions of its own.
Merging this is blocked by https://github.com/datalad/datalad/issues/2124
since it seems it will break datalad. I checked all the other special
remotes and they will be ok.
This commit was supported by the NSF-funded DataLad project.
It's left up to the special remote to detect when git-annex is new enough
to support the message; an old git-annex will blow up.
This commit was supported by the NSF-funded DataLad project.
Not yet called by Command.Export.
WebDAV needs this to clean up empty collections. Also, example.sh turned
out to not be cleaning up directories when removing content
from them, so it made sense for it to use this.
Remote.Directory did not need it, and since its cleanup method for empty
directories is more efficient than what Command.Export will need to do
to find empty directories, it uses Nothing so that extra work can be
avoided.
This commit was sponsored by Thom May on Patreon.
External special remotes will refuse to operate on keys with spaces in
their names. That has never worked correctly due to the design of the
external special remote protocol. Display an error message suggesting
migration.
Not super happy with this, but it's a pragmatic solution. Better than
complicating the external special remote interface and all external special
remotes.
Note that I only made it use SafeKey in Request, not Response. git-annex
does not construct a Response, so that would not add any safety. And
presumably, if git-annex avoids feeding any such keys to an external
special remote, it will never have a reason to make a Response using such a
key. If it did, it would result in a protocol error anyway.
There's still a Serializeable instance for Key; it's used by P2P.Protocol.
There, the Key is always in the final position, so it's ok if it contains
spaces.
Note that the protocol documentation has been fixed to say that the File
may contain spaces. One way that can happen, even though the Key can't,
is when using direct mode, and the work tree filename contains spaces.
When sending such a file to the external special remote the worktree
filename is used.
This commit was sponsored by Thom May on Patreon.
Useful for things like ipfs that don't use regular urls.
An external special remote can add a regular url to a key, and then
git-annex get will download it from the web. But for ipfs, we want to
instead tell git-annex that the uri uses OtherDownloader. Before this
change, the external special remote protocol lacked a way to do that.
