The container capture preserved the app's ownership (e.g. www-data 0640), so
restic still hit permission denied on the staging copy. chown the staging tree
to the backup user after capture (modes unchanged, so the owner reads fine);
real ownership is reapplied from the descriptor on restore.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Signed-off-by: librelad <librelad@digitalangels.vip>
Reads files the backup user can't see from the host (container-owned, e.g.
Nextcloud's www-data data dir) by streaming them out THROUGH the container
(docker exec tar) — no host root, no host read perms, works rooted + rootless.
Extracts to staging as plain files so restic keeps full dedup + per-file
restore (not a piped tar blob); the live path is excluded from the snapshot.
Restore streams the staging copy back through a throwaway in-namespace
container that recreates the tree with the app's uid:gid.
Declared via a libreportal.backup.files compose label; Nextcloud (html, 33:33)
is the first to use it. Live capture failure falls back to stop-snapshot-start.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Signed-off-by: librelad <librelad@digitalangels.vip>
