Binds the store to one path on one filesystem.
Injected filesystem access.
Absolute path of the OTP-settings JSON file.
Reads the configured OTP settings.
The settings, defaulting to the Telegram channel when unset or unreadable.
Persists the OTP delivery channel atomically.
The channel to store.
Deletes staged files a killed write left beside the file.
How many were removed, or why the directory could not be read.
Persists the OTP delivery channel to a JSON file on a shared volume.