Mousturise Sensor Wemos D1 MQTT JSON

#include <ESP8266WiFi.h>
#include <PubSubClient.h>
#include <ArduinoJson.h>

#define wifi_ssid "MKI"
#define wifi_password "tidaktau"
#define mqtt_server "192.168.1.200"      //Broker's IP Address
#define sensor_data_topic "sensor/data"

int moist_Sensor = 0; // A0
int PUMP_PIN = D4;    // D2
String moist;
int persen;

WiFiClient espClient;
PubSubClient client(espClient);

void setup() {



  pinMode(PUMP_PIN, OUTPUT);
  Serial.begin(115200);
  setup_wifi();
  client.setServer(mqtt_server, 1883);
  client.setCallback(callback);
  delay(1000);
}

void setup_wifi() {
  delay(10);
  Serial.println();
  Serial.print("Connecting to ");
  Serial.println(wifi_ssid);

  WiFi.begin(wifi_ssid, wifi_password);

  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }

  Serial.println("");
  Serial.println("WiFi connected");
  Serial.println("IP address: ");
  Serial.println(WiFi.localIP());
}

void callback(char* topic, byte* payload, unsigned int length) {
  Serial.print("Message arrived [");
  Serial.print(topic);
  Serial.print("] ");
  String pay_load="";
  for (int i = 0; i < length; i++) {
    pay_load+=(char)payload[i];
  }
  Serial.print(pay_load);
  Serial.println();

  if (pay_load == "on") {
    Serial.println("Turning On");
    digitalWrite(PUMP_PIN, HIGH);
  }
  else {
    Serial.println("Turning Off");
    digitalWrite(PUMP_PIN, LOW);
  }

}

void reconnect() {
  while (!client.connected()) {
    Serial.print("Attempting MQTT connection...");
    // if (client.connect("ESP_PUMP")) {
    if (client.connect("ESP_PUMP")) {
      Serial.println("connected");
      client.subscribe("sensor/reply");
    } else {
      Serial.print("failed, rc=");
      Serial.print(client.state());
      Serial.println(" try again in 5 seconds");
      // Wait 5 seconds before retrying
      delay(5000);
    }
  }
}

void loop() {
  if (!client.connected()) {
    reconnect();
  }
  int m = analogRead(moist_Sensor);

  persen = map(m, 0, 1024, 100, 0);
  moist=String(persen).c_str();
  String sensor = moist;
  StaticJsonBuffer<100> jsonBuffer;
  JsonObject& root = jsonBuffer.createObject();
  root["analog"] = m;
  root["persen"] = persen;
  //root.printTo(Serial);
  //Serial.println(sensor);
  client.loop();
  //client.publish(sensor_data_topic, String(sensor).c_str(), true);

char JSONmessageBuffer[100];
  root.printTo(JSONmessageBuffer, sizeof(JSONmessageBuffer));
  Serial.println("Sending message to MQTT topic..");
  Serial.println(JSONmessageBuffer);

  client.publish(sensor_data_topic, JSONmessageBuffer, true);


  //client.publish(sensor_data_topic, String(sensor).c_str(), true);
  delay(1000);
}