code: func (p *Processor) SetRawHandler(id uint16, msgRawHandler MsgHandler) {
  	if id >= uint16(len(p.msgInfo)) {
  		log.Fatal("message id %v not registered", id)
  	}
  
  	p.msgInfo[id].msgRawHandler = msgRawHandler
  }
docs: // It's dangerous to call the method on routing or marshaling (unmarshaling)