true
end
- # If trash_at is updated without touching delete_at, automatically
- # update delete_at to a sensible value.
def default_trash_interval
if trash_at_changed? && !delete_at_changed?
+ # If trash_at is updated without touching delete_at,
+ # automatically update delete_at to a sensible value.
if trash_at.nil?
self.delete_at = nil
else
self.delete_at = trash_at + Rails.configuration.default_trash_lifetime.seconds
end
+ elsif !trash_at || !delete_at || trash_at > delete_at
+ # Not trash, or bogus arguments? Just validate in
+ # validate_trash_and_delete_timing.
+ elsif delete_at_changed? && delete_at >= trash_at
+ # Fix delete_at if needed, so it's not earlier than the expiry
+ # time on any permission tokens that might have been given out.
+
+ # In any case there are no signatures expiring after now+TTL.
+ # Also, if the existing trash_at time has already passed, we
+ # know we haven't given out any signatures since then.
+ earliest_delete = [
+ @validation_timestamp,
+ trash_at_was,
+ ].compact.min + Rails.configuration.blob_signature_ttl.seconds
+
+ # The previous value of delete_at is also an upper bound on the
+ # longest-lived permission token. For example, if TTL=14,
+ # trash_at_was=now-7, delete_at_was=now+7, then it is safe to
+ # set trash_at=now+6, delete_at=now+8.
+ earliest_delete = [earliest_delete, delete_at_was].compact.min
+
+ # If delete_at is too soon, use the earliest possible time.
+ if delete_at < earliest_delete
+ self.delete_at = earliest_delete
+ end
end
end
def validate_trash_and_delete_timing
if trash_at.nil? != delete_at.nil?
errors.add :delete_at, "must be set if trash_at is set, and must be nil otherwise"
+ elsif delete_at && delete_at < trash_at
+ errors.add :delete_at, "must not be earlier than trash_at"
end
-
- if delete_at
- if delete_at < trash_at
- errors.add :delete_at, "must not be earlier than trash_at"
- else
- earliest_delete = ([@validation_timestamp, trash_at_was].compact.min +
- Rails.configuration.blob_signature_ttl.seconds)
- if delete_at < earliest_delete
- self.delete_at = earliest_delete
- end
- end
- end
-
true
end
end