toJson method

Implementation

Map<String, dynamic> toJson() => {
      "id": id,
      "app_id": appID,
      "robot_id": robotID,
      "user_id": userID,
      "msg_type": msgType,
      "payload": payload != null ? base64Encode(payload!) : null,
      "encrypted": encrypted,
      "version": version?.toString(),
    };