// Copyright Siwat INC(tm) 2019
// Created by Siwat Sirichai
// ESPCommander EXTENDED v1.2
void espcommander(String topic, String command)  { //the command is in json format!
    StaticJsonDocument<200> doc;
    DeserializationError error = deserializeJson(doc, json);
    if (error) {
      Serial.print(F("deserializeJson() failed: "));
      Serial.println(error.c_str());
    return;
  }
  String command = doc["command"];
  String value = doc["value"];
}