def get_docs_to_commit(self):
        try:
            spec = {'synced': False}
            fields = {'_id': 0}
            cur = self.db.docs.find(spec, fields)
        except Exception as e:
            raise DatabaseException(e)
        return list(cur)
def encode(self):
        return {"rx_sw_if_index": self._rx_index,
                "tx_sw_if_index": self._tx_index, "nh": self._nh_addr}