NodeMcu, IBM IOT cloud(Bluemix), DHT sensor

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

// --------------------------------------------------------------------------------------------
//        UPDATE CONFIGURATION TO MATCH YOUR ENVIRONMENT
// --------------------------------------------------------------------------------------------

// Watson IoT connection details
#define MQTT_HOST "su1efs.messaging.internetofthings.ibmcloud.com"
//change  su1efs
#define MQTT_PORT 1883
#define MQTT_DEVICEID "d:su1efs:ESP8266:dev01"
//change  su1efs
#define MQTT_USER "use-token-auth"
#define MQTT_TOKEN "Akash_Yanakandla" // change your auth_id : 
#define MQTT_TOPIC "iot-2/evt/status/fmt/json"
#define MQTT_TOPIC_DISPLAY "iot-2/cmd/display/fmt/json"

// Add GPIO pins used to connect devices

#define DHT_PIN 4 // GPIO pin the data line of the DHT sensor is connected to

// Specify DHT11 (Blue) or DHT22 (White) sensor
#define DHTTYPE DHT11


// Add WiFi connection information
char ssid[] = "Akash Yanakandla";     //  your network SSID (name) 
char pass[] = "12332112";  // your network password


// --------------------------------------------------------------------------------------------
//        SHOULD NOT NEED TO CHANGE ANYTHING BELOW THIS LINE
// --------------------------------------------------------------------------------------------
//Adafruit_NeoPixel pixel = Adafruit_NeoPixel(1, RGB_PIN, NEOPIXEL_TYPE);
DHT dht(DHT_PIN, DHTTYPE);


// MQTT objects
void callback(char* topic, byte* payload, unsigned int length);
WiFiClient wifiClient;
PubSubClient mqtt(MQTT_HOST, MQTT_PORT, callback, wifiClient);

// variables to hold data
StaticJsonDocument<100> jsonDoc;
JsonObject payload = jsonDoc.to<JsonObject>();
JsonObject status = payload.createNestedObject("d");
static char msg[50];

float h = 0.0;
float t = 0.0;



void callback(char* topic, byte* payload, unsigned int length) {
  // handle message arrived
  Serial.print("Message arrived [");
  Serial.print(topic);
  Serial.print("] : ");

  payload[length] = 0; // ensure valid content is zero terminated so can treat as c-string
  Serial.println((char *)payload);
}

void setup() {
 // Start serial console
  Serial.begin(115200);
  Serial.setTimeout(2000);
  while (!Serial) { }
  Serial.println();
  Serial.println("ESP8266 Sensor Application");

  // Start WiFi connection
  WiFi.mode(WIFI_STA);
  WiFi.begin(ssid, pass);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("");
  Serial.println("WiFi Connected");

  // Start connected devices
  dht.begin();
//  pixel.begin();

  // Connect to MQTT - IBM Watson IoT Platform
  if (mqtt.connect(MQTT_DEVICEID, MQTT_USER, MQTT_TOKEN)) {
    Serial.println("MQTT Connected");
    mqtt.subscribe(MQTT_TOPIC_DISPLAY);

  } else {
    Serial.println("MQTT Failed to connect!");
    ESP.reset();
  }
}

void loop() {
  mqtt.loop();
  while (!mqtt.connected()) {
    Serial.print("Attempting MQTT connection...");
    // Attempt to connect
    if (mqtt.connect(MQTT_DEVICEID, MQTT_USER, MQTT_TOKEN)) {
      Serial.println("MQTT Connected");
      mqtt.subscribe(MQTT_TOPIC_DISPLAY);
      mqtt.loop();
    } else {
      Serial.println("MQTT Failed to connect!");
      delay(5000);
    }
  }
  h = dht.readHumidity();
  t = dht.readTemperature(); // uncomment this line for centigrade
  // t = dht.readTemperature(true); // uncomment this line for Fahrenheit

  // Check if any reads failed and exit early (to try again).
  if (isnan(h) || isnan(t)) {
    Serial.println("Failed to read from DHT sensor!");
  } else {
    // Set RGB LED Colour based on temp
//    b = (t < ALARM_COLD) ? 255 : ((t < WARN_COLD) ? 150 : 0);
//    r = (t >= ALARM_HOT) ? 255 : ((t > WARN_HOT) ? 150 : 0);
//    g = (t > ALARM_COLD) ? ((t <= WARN_HOT) ? 255 : ((t < ALARM_HOT) ? 150 : 0)) : 0;
////    pixel.setPixelColor(0, r, g, b);
//    pixel.show();

    // Send data to Watson IoT Platform
    status["temp"] = t;
    status["humidity"] = h;
    serializeJson(jsonDoc, msg, 50);
    Serial.println(msg);
    if (!mqtt.publish(MQTT_TOPIC, msg)) {
      Serial.println("MQTT Publish failed");
    }
  }

  // Pause - but keep polling MQTT for incoming messages
  for (int i = 0; i < 10; i++) {
    mqtt.loop();
    delay(1000);
  }
}