code: func ParseWebRTCSignalMessage(msg string) (*WebRTCSignalMessage, error) {
  	// All messages are text (utf-8 encoded at present)
  	if !utf8.Valid([]byte(msg)) {
  		return nil, errInvalidChar
  	}
  
  	w := &WebRTCSignalMessage{}
  	if err := json.Unmarshal([]byte(msg), w); err != nil {
  		return nil, err
  	}
  
  	if err := validateOperation(w.Type); err != nil {
  		return nil, err
  	}
  
  	return w, nil
  }
docs: // ParseWebRTCSignalMessage parses the web rtc command/message