Books.atom_timestamp returned Books.timestamp (date added), which is
set at import and never changes. OPDS clients use atom:updated to
decide whether a book has changed on the server, so cover swaps,
metadata edits, and any other post-import change were invisible to
sync clients; they would keep serving the stale cover and title
until a manual refresh.
Atom RFC 4287 defines updated as "the most recent instant in time
when an entry or feed was modified", and Calibre already tracks that
field as last_modified, bumping it on every metadata and cover edit.
Switching the property to return last_modified (with a fallback to
timestamp when last_modified is NULL) aligns Calibre-Web's behaviour
with the Atom contract.
This change only affects the OPDS feed's atom:updated element. Kobo
sync uses its own last_modified comparison path, so it is unaffected.
calibredb export writes <uuid>.jpg next to <uuid>.<format> by
default, leaving an unused cover image in /tmp/calibre_web for
every download that goes through do_calibre_export. The cover
file is never read by calibre-web (cover serving uses a separate
path), so it is pure waste of disk space and IO.
Pass --dont-save-cover, paired with the existing --dont-write-opf,
to skip the unwanted side-effect at the source. Verified that
none of the three do_calibre_export call sites (download via
do_download_file, email via tasks/mail.py, kepubify via
tasks/convert.py) read the cover sibling.
When config_embed_metadata is enabled with config_binariesdir or
config_kepubifypath set, do_download_file stages a copy of every
downloaded book under get_temp_dir() but never removes it. A bulk
OPDS or Kobo sync can fill the host filesystem in minutes; the
effect is amplified for comic formats (CBZ/CBR), where each
staged file can run to hundreds of MB or several GB. Once the
disk fills, downloads silently 404 and a container restart does
not recover the space.
Add an after_this_request hook that removes the staged copy after
the response is sent, gated on filename == get_temp_dir() so the
non-embed and gdrive-direct paths are untouched.
haraldpdl