ERROR: Cannot deserialize to a Python object: u'(...)/repo/metadata/current/root.json'

If @/repo/metadata/current/root.json@ is empty, then TUF will keep failing to deserialize its content with an error every one minute.

Maybe we could enclose this deserialization atempt with a try/except clause and fail gracefully with a warning instead of an error.

Also, why is that file empty?

(from redmine: created on 2014-10-23)