def get_last_tid(self):
        try:
            spec = {'tid': {'$gt': 0}}
            sort = [('tid', -1)]
            row = self.db.docs.find_one(spec, sort=sort)
        except Exception as e:
            raise DatabaseException(e)
        if row:
            return row['tid']
        return 0
def current_label_end(self):
        if self.current_label and self.message:
            return self.message.get_label_range(self.current_label, self.proto_view, False)[1]
        else:
            return -1