DHT11 Temperature Sensor

#include < ESP8266WiFi.h >
#include < PubSubClient.h >
#include <ArduinoJson.h>
#include <DHT.h>
  
// define message ID and its interval 
#define REPORTING_INTERVAL 15000
#define MSG_ID 30001 // Your message ID given during message definition 

// define the sensor interface 
#define DHT_TYPE DHT11
#define DHT_PIN 5 // GPIO 5 for D1 Pin 

// define device and wifi details 
#define WIFI_SSID "WIFI_SSID" // Your Wifi name 
#define WIFI_PSK "WIFI_PASSWORD" // Your Wifi password 
#define DOMAIN_KEY "DOMAIN_KEY" // Your platform domain key 
#define API_KEY "API_KEY" // Your platform API key
#define DEVICE_ID "DEVICE_ID" // Your device ID 
#define DEVICE_MODEL "DEVICE_MODEL" // Your device model 
#define FIRMWARE_VER "DEVICE_FW_VERSION" // Your device's firmware version 

// define Boodskap Platform MQTT configurations 
#define MQTT_SERVER "orientation.boodskap.io"
#define MQTT_PORT 1883
String mqttUser = "DEV_" + String(DOMAIN_KEY);
String mqttPassword = API_KEY;
String clientid = "DEV_" + String(DEVICE_ID);
String topic =
  "/" + String(DOMAIN_KEY) + "/device/" + String(DEVICE_ID) + "/msgs/" + String(DEVICE_MODEL) + "/" + String(FIRMWARE_VER) + "/" + String(MSG_ID);

DHT dht(DHT_PIN, DHT_TYPE);
uint32_t lastReport = 0;
WiFiClient espClient;
PubSubClient client(espClient);

void setup() {
  Serial.begin(115200);
  dht.begin();
  WiFi.begin(WIFI_SSID, WIFI_PSK);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.println("Connecting to WiFi .....");
  }
  Serial.println("Connected to the WiFi network");
  client.setServer(MQTT_SERVER, MQTT_PORT);
}

void loop() {
  if ((millis() - lastReport) >= REPORTING_INTERVAL) {
    sendStatusMessage();
    lastReport = millis();
  }
}

// Send Messages to the platform 
void sendStatusMessage() {
  
  StaticJsonDocument < 256 > data;
  float h = dht.readHumidity();
  float t = dht.readTemperature();
  
  if (isnan(h) || isnan(t)) {
    return;
  } else {
    data["temperature"] = t;
    data["humidity"] = h;
  }
  
  while (!client.connected()) {
    Serial.println("Connecting to MQTT...");
    Serial.println(clientid);
    if (client.connect(clientid.c_str(), mqttUser.c_str(), mqttPassword.c_str())) {
      Serial.println("connected");
    } else {
      Serial.println("failed with state ");
      Serial.println(client.state());
      delay(2000);
    }
  }
  
  char buffer[256];
  serializeJson(data, buffer);
  client.publish(topic.c_str(), buffer);
  client.disconnect();
}