The restore dialog asked GET /api/admin/backups/{id}/summary for the
contents of a copy, and the route read the whole stored copy to answer:
every piece opened, every measurement parsed, the rest validated. On an
account of 1.8 million readings on slow hardware that took about two
minutes. The dialog stopped waiting after 15 s and said the contents
could not be read, and its automatic retry made the server read the
whole copy a second time.
The copy passes through the process once anyway while it is written, so
the preview is worked out there and kept on the row (DataBackup.preview,
migration 0364): the summarizeBackup counts, the schema version, and
the inner key ids with the sections they sit in and one sample value
each. Every creation path goes through storeBackupBlob (the weekly and
manual pass, and an upload), so every new copy carries one. The column
is plain JSON: counts and dates only, and the samples are ciphertext
that stands for what is inside the copy, which a key rotation must not
re-seal.
The route answers from it without opening the copy. Both verdicts are
taken again on every read, from what the preview keeps: whether this
release restores the schema version, and whether this server holds the
keys the copy needs. The pieces are still counted against the row, so
a copy that lost one is refused as the restore and the download refuse
it. A preview names the copy it describes and is ignored once the copy
changes; converting a single stored value into pieces carries it over.
A copy written before this has no preview. It is read whole once, as
before, and the result is kept on the row, so it is slow only the first
time; concurrent requests for the same copy share the one read.
Only a file that fails the schema answers 422 "Backup payload failed
schema validation". Read refusals keep their codes; anything else is
the server failing and answers 500.
The dialog no longer retries the preview, waits up to 55 s, and when it
stops waiting on an older copy it says the copy is still being read and
to open the dialog again in a few minutes.
Refs #1031
The shortest value either codec writes is 40 base64 characters. A
shorter string under an ...Encrypted member is not ciphertext, and
reading it as a legacy value would have made a restore demand the v1
key for a field that holds none.
The admin wipe of every account is the operator clearing their own host,
and the bucket's copies are the documented way back from a wipe pressed
by mistake, so it writes no off-host deletion request. Deleting an
account, deleting a managed profile and "Delete all data" still do.
The backup runbook no longer says the worker never deletes an object: it
lists the grant the worker needs (DeleteObject included), when objects
are deleted, the version-4 envelope, the lifecycle check and how to
rotate the off-host key. The rotation runbook no longer says backups are
covered: rotation reaches a backup's envelope, not the content a restore
writes back, and a retired key stays needed until no backup lists it.
The privacy notice beside account deletion says the same about off-host
copies.
A failed import records its failure in a plain try block, and the
extraction test that inflates past the 64 MiB floor gets the time it
needs on a loaded runner.
A backup carries every encrypted column as the stored ciphertext, and a
restore writes it back verbatim. Key rotation re-seals the stored copy's
envelope but cannot reach inside it, so a copy taken before a rotation
still needs the retired key. Without it the restore went through and
left rows no reader can open.
The restore, the restore preview, the admin upload and the monthly
restore drill now collect the key ids of every inner ciphertext value,
hold them against ENCRYPTION_KEYS and decrypt one value per key. A
missing key, or an id configured with different key material, is
refused before anything is deleted, with the key id named. The restore
status and the preview say which key to put back.
The restore also checks, inside its transaction, that it added no
reference from the account's rows to rows another account owns. The
check is derived from the schema's foreign keys rather than written per
section, so the tag and category upserts keyed on a global key are
covered along with every link table. The illness parent update is
scoped to the owner as well.
The off-host listing now follows every page: the first page held only
the oldest dates, so the drill could read an old object and report the
chain as stale.
Marc-André Bombeck