importfeed: Use caching database to avoid needing to list urls on every
run, and avoid using too much memory.
Benchmarking in my podcasts repo, importfeed got 1.42 seconds faster,
and memory use dropped from 203000k to 59408k.
Database.ImportFeed is Database.ContentIdentifier with the serial number
filed off. There is a bit of code duplication I would like to avoid,
particularly recordAnnexBranchTree, and getAnnexBranchTree. But these use
the persistent sqlite tables, so despite the code being the same, they
cannot be factored out.
Since this database includes the contentidentifier metadata, it will be
slightly redundant if a sqlite database is ever added for metadata. I
did consider making such a generic database and using it for this. But,
that would then need importfeed to update both the url database and the
metadata database, which is twice as much work diffing the git-annex
branch trees. Or would entagle updating two databases in a complex way.
So instead it seems better to optimise the database that
importfeed needs, and if the metadata database is used by another command,
use a little more disk space and do a little bit of redundant work to
update it.
Sponsored-by: unqueued on Patreon
This is groundwork for making special remotes like borg be skipped by
sync when on an offline drive.
Added AVAILABILITY UNAVAILABLE reponse and the UNAVAILABLERESPONSE extension
to the external special remote protocol. The extension is needed because
old git-annex, if it sees that response, will display a warning
message. (It does continue as if the remote is globally available, which
is acceptable, and the warning is only displayed at initremote due to
remote.name.annex-availability caching, but still it seemed best to make
this a protocol extension.)
The remote.name.annex-availability git config is no longer used any
more, and is documented as such. It was only used by external special
remotes to cache the availability, to avoid needing to start the
external process every time. Now that availability is queried as an
Annex action, the external is only started by sync (and the assistant),
when they actually check availability.
Sponsored-by: Nicholas Golder-Manning on Patreon
Support VERSION 2 in the external special remote protocol, which is
identical to VERSION 1, but avoids external remote programs neededing to
work around the above bug. External remote program that support
exporttree=yes are recommended to be updated to send VERSION 2.
Sponsored-by: Kevin Mueller on Patreon
When importing from versioned remotes, fix tracking of the content of
deleted files.
Only S3 supports versioning so far, so only it was affected.
But, the draft import/export interface for external remotes also seemed to
need a change, so that versionedExport could be set.
