This is similar to the pusher thread, but a separate thread because git
pushes can be done in parallel with exports, and updating a big export
should not prevent other git pushes going out in the meantime.
The exportThread only runs at most every 30 seconds, since updating an
export is more expensive than pushing. This may need to be tuned.
Added a separate channel for export commits; the committer records a
commit in that channel.
Also, reconnectRemotes records a dummy commit, to make the exporter
thread wake up and make sure all exports are up-to-date. So,
connecting a drive with a directory special remote export will
immediately update it, and getting online will automatically
update S3 and WebDAV exports.
The transfer queue is not involved in exports. Instead, failed
exports are retried much like failed pushes.
This commit was sponsored by Ewen McNeill.
Split exportRemotes out from syncDataRemotes; the parts of the assistant
that upload keys and drop keys from remotes don't apply to exports,
because those operations are not supported.
Some parts of the assistant and webapp do operate on both
syncDataRemotes and exportRemotes. Particularly when downloading from
either of them. Added a downloadRemotes that combines both.
With this, the assistant should download from exports, but it won't yet
upload changes to them.
This commit was sponsored by Fernando Jimenez on Patreon.
Same as is done for all other transfers of content, so the webapp will
display progress bars etc.
This commit was sponsored by Anthony DeRobertis on Patreon.
The bug occurred when closeDb was not called, and garbage collection of
the DbHandle didn't give the workerThread time to shut down. Fixed by
exiting the runSqlite action when a commit is made.
(MultiWriter mode already forked off a runSqlite action, so avoided the
problem.)
This commit was sponsored by Brock Spratlen on Patreon.
Now when one repository has exported a tree, another repository can get
files from the export, after syncing.
There's a bug: While the database update works, somehow the database on
disk does not get updated, and so the database update is run the next
time, etc. Wasn't able to figure out why yet.
This commit was sponsored by Ole-Morten Duesund on Patreon.
Use ExportTree rather than ExportedLocation for retrieveKeyFile and
checkPresent. When another remote exported the content, ExportTree will
be populated, but ExportedLocation will not be.
It would be possible to implement storeKey to exports as well, but it
risks performing a lot of unncessary work when another repository
already stored the key on the export and the local repository doesn't
know about it.
The only way to avoid that work would be for storeKey to use checkPresentExport
before uploading. But, the other repository could have changed the
exported tree as well, so that can't be trusted, and if it were used in
storeKey, could result in bad information getting into the location log.
This commit was sponsored by Bruno BEAUFILS on Patreon.
New table needed to look up what filenames are used in the currently
exported tree, for reasons explained in export.mdwn.
Also, added smart constructors for ExportLocation and ExportDirectory to
make sure they contain filepaths with the right direction slashes.
And some code refactoring.
This commit was sponsored by Francois Marier on Patreon.
There does not seem to be a use case for supporting that, and it would
need a lot of complication to support it in a way that allows eventual
consistency when two repositories are updating the same export.
This commit was sponsored by Henrik Riomar on Patreon.
Done to avoid a "tmp" directory appearing in webdav exports.
Also affects non-export webdav remotes, so interrupted uploads using the
old path will not overwrite it. However, PUT is quite likely to be
implemented atomically on web servers anyway, so I doubt this will cause
problems.
The subtle part of this is what happens when the remote fails to remove
an empty directory. The removal from the export needs to fail in that
case, so the removal will be tried again later. However, removeExportLocation
has already been run and changed the export db, so if the next run
checks getExportLocation, it might decide nothing remains to be done,
leaving the empty directory.
Dealt with that by making removeEmptyDirectories, handle a failure
by calling addExportLocation, reverting the database changes so the next
run will be guaranteed to try deleting the empty directory again.
This commit was sponsored by Thomas Hochstein on Patreon.
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.
