If the message is a batch message validate each message in the batch,
        otherwise add the message to the node's clientInBox.
        But node return a Nack message if View Change in progress
        :param msg: a client message
        :param frm: the name of the client that sent this `msg`

def unpackClientMsg(self, msg, frm):
        """
        If the message is a batch message validate each message in the batch,
        otherwise add the message to the node's clientInBox.
        But node return a Nack message if View Change in progress
        :param msg: a client message
        :param frm: the name of the client that sent this `msg`
        """

        if isinstance(msg, Batch):
            for m in msg.messages:
                # This check is done since Client uses NodeStack (which can
                # send and receive BATCH) to talk to nodes but Node uses
                # ClientStack (which cannot send or receive BATCH).
                # TODO: The solution is to have both kind of stacks be able to
                # parse BATCH messages
                if m in (ZStack.pingMessage, ZStack.pongMessage):
                    continue
                m = self.clientstack.deserializeMsg(m)
                self.handleOneClientMsg((m, frm))
        else:
            msg_dict = msg.as_dict if isinstance(msg, Request) else msg
            if isinstance(msg_dict, dict):
                if self.view_changer.view_change_in_progress and self.is_request_need_quorum(msg_dict):
                    self.discard(msg_dict,
                                 reason="view change in progress",
                                 logMethod=logger.debug)
                    self.send_nack_to_client((idr_from_req_data(msg_dict),
                                              msg_dict.get(f.REQ_ID.nm, None)),
                                             "Client request is discarded since view "
                                             "change is in progress", frm)
                    return
            self.postToClientInBox(msg, frm)