MQTT publishing DHT11 sensor on Arduino

/*
 Basic MQTT example
*/

#include <SPI.h>
#include <Ethernet.h>
#include <PubSubClient.h>

// Our first sensor, a cheap DHT11 temperature and humidty sensor
#include <DHT.h>
#define DHTPIN 7
#define DHTTYPE DHT11 //21 or 22 also an option
DHT dht(DHTPIN, DHTTYPE);
unsigned long readTime;

// Update these with values suitable for your network.
byte mac[]    = {  0xDE, 0xED, 0xBA, 0xFE, 0xFE, 0xED };
IPAddress ip(192, 168, 1, 151);
IPAddress server(192, 168, 1, 99);
char message_buff[100]; // this buffers our incoming messages so we can do something on certain commands

EthernetClient ethClient;
PubSubClient client(ethClient);


void callback(char* topic, byte* payload, unsigned int length) {
  Serial.print("Message arrived [");
  Serial.print(topic);
  Serial.print("] ");
  int i=0;
  for (i=0;i<length;i++) {
    Serial.print((char)payload[i]);
    message_buff[i] = payload[i];
  }
  message_buff[i] = '\0';
  String msgString = String(message_buff);
  if (msgString.equals("OFF")) {
    client.publish("openhab/himitsu/command","acknowedging OFF");
  }
  else if(msgString.equals("ON")){
    client.publish("openhab/himitsu/command","acknowedging ON");
  }
  Serial.println();
}


void reconnect() {
  // Loop until we're reconnected
  while (!client.connected()) {
    Serial.print("Attempting MQTT connection...");
    // Attempt to connect
    if (client.connect("arduinoClient")) {
      Serial.println("connected");
      // Once connected, publish an announcement...
      client.publish("openhab","himitsu sensor, reporting in");
      // ... and resubscribe
      client.subscribe("openhab/himitsu/command");
    } else {
      Serial.print("failed, rc=");
      Serial.print(client.state());
      Serial.println(" try again in 5 seconds");
      // Wait 5 seconds before retrying
      delay(5000);
    }
  }
}

void setup()
{
  Serial.begin(57600);

  client.setServer("192.168.1.99", 1883);
  client.setCallback(callback);

  Ethernet.begin(mac);
  
  dht.begin();
  // Allow the hardware to sort itself out
  delay(1500);
  Serial.println(Ethernet.localIP());
  readTime = 0;
}

void loop()
{
  
  if (!client.connected()) {
    reconnect();
  }
  
  client.loop();
  
  //check if 5 seconds has elapsed since the last time we read the sensors. 
  if(millis() > readTime+60000){
    sensorRead();
  }
  
}

void sensorRead(){
  readTime = millis();
 // Reading temperature or humidity takes about 250 milliseconds!
  // Sensor readings may also be up to 2 seconds 'old' (its a very slow sensor)
  float h = dht.readHumidity();
  // Read temperature as Celsius (the default)
  float t = dht.readTemperature();
  // Read temperature as Fahrenheit (isFahrenheit = true)
  float f = dht.readTemperature(true);

  // Check if any reads failed and exit early (to try again).
  if (isnan(h) || isnan(t) || isnan(f)) {
    Serial.println("Failed to read from DHT sensor!");
    return;
  }

  // Compute heat index in Fahrenheit (the default)
  float hif = dht.computeHeatIndex(f, h);
  // Compute heat index in Celsius (isFahreheit = false)
  float hic = dht.computeHeatIndex(t, h, false);

  char buffer[10];
  dtostrf(t,0, 0, buffer);
  client.publish("openhab/himitsu/temperature",buffer);
  //Serial.println(buffer);
  dtostrf(h,0, 0, buffer);
  client.publish("openhab/himitsu/humidity",buffer);
  
  //client.publish("inTopic/humidity",sprintf(buf, "%f", h));
  /*Serial.print("Humidity: ");
  Serial.print(h);
  Serial.print(" %\t");
  Serial.print("Temperature: ");
  Serial.print(t);
  Serial.print(" *C ");
  Serial.print(f);
  Serial.print(" *F\t");
  Serial.print("Heat index: ");
  Serial.print(hic);
  Serial.print(" *C ");
  Serial.print(hif);
  Serial.println(" *F"); */
}

server Raspberry Pi3 (mqtt, Node Red) + Arduino Uno+ethernet shield w5100 (DHT11 + 2 diodes switch and slider)
sketch:

#include <SPI.h>
#include <Ethernet.h>
#include <PubSubClient.h>

// Our first sensor, a cheap DHT11 temperature and humidty sensor
#include <DHT.h>
#define DHTPIN 2
#define DHTTYPE DHT11 //21 or 22 also an option
DHT dht(DHTPIN, DHTTYPE);
unsigned long readTime;

// Update these with values suitable for your network.
byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };
IPAddress ip(192, 168, 0, 28);
IPAddress server(192, 168, 0, 15);
char message_buff[100]; // this buffers our incoming messages so we can do something on certain commands

EthernetClient ethClient;
PubSubClient client(ethClient);

const int ledPin6 = 6;
const int ledPin7 = 7;

void callback(char* topic, byte* message, unsigned int length) {
Serial.print("Message arrived on topic: ");
Serial.print(topic);
Serial.print(". Message: ");
String messageTemp;
for (int i = 0; i < length; i++) {
Serial.print((char)message[i]);
messageTemp += (char)message[i];
}
Serial.println();
// Feel free to add more if statements to control more Pins with MQTT
// If a message is received on the topic home/livingroom/arduino/ledPin6
// It's a value between 0 and 255 to adjust the LED brightness
if(String(topic)=="home/livingroom/arduino/ledPin6"){
Serial.print("Changing Digital Pin 6 Brithness to ");
Serial.print(messageTemp);
analogWrite(ledPin6, messageTemp.toInt());
}
// If a message is received on the topic home/livingroom/arduino/ledPin7,
//you check if the message is either 1 or 0. Turns the Arduino Digital Pin according to the message
if(String(topic)=="home/livingroom/arduino/ledPin7"){
Serial.print("Changing Digital Pin 7 to ");
if(messageTemp == "1"){
digitalWrite(ledPin7, HIGH);
Serial.print("On");
}
else if(messageTemp == "0"){
digitalWrite(ledPin7, LOW);
Serial.print("Off");
}
}
Serial.println();
}

void reconnect() {
// Loop until we're reconnected
while (!client.connected()) {
Serial.print("Attempting MQTT connection...");
// Attempt to connect
if (client.connect("arduinoClient")) {
Serial.println("connected");
// Subscribe or resubscribe to a topic
// You can subscribe to more topics (to control more LEDs in this example)
client.subscribe("home/livingroom/arduino/ledPin6");
client.subscribe("home/livingroom/arduino/ledPin7");
} else {
Serial.print("failed, rc=");
Serial.print(client.state());
Serial.println(" try again in 5 seconds");
// Wait 5 seconds before retrying
delay(5000);
}
}
}

void setup()
{
pinMode(ledPin6, OUTPUT);
pinMode(ledPin7, OUTPUT);

Serial.begin(57600);

client.setServer("192.168.0.15", 1883); // can be replaced by: client.setServer(server, 1883);
client.setCallback(callback);

Ethernet.begin(mac);

dht.begin();
// Allow the hardware to sort itself out
delay(1500);
Serial.println(Ethernet.localIP());
readTime = 0;
}

void loop()
{

if (!client.connected()) {
reconnect();
}

client.loop();

//check if 5 seconds has elapsed since the last time we read the sensors.
if(millis() > readTime+6000){
sensorRead();
}

}

void sensorRead(){
readTime = millis();
// Reading temperature or humidity takes about 250 milliseconds!
// Sensor readings may also be up to 2 seconds 'old' (its a very slow sensor)
float h = dht.readHumidity();
// Read temperature as Celsius (the default)
float t = dht.readTemperature();
// Read temperature as Fahrenheit (isFahrenheit = true)
float f = dht.readTemperature(true);

// Check if any reads failed and exit early (to try again).
if (isnan(h) || isnan(t) || isnan(f)) {
Serial.println("Failed to read from DHT sensor!");
return;
}

// Compute heat index in Fahrenheit (the default)
float hif = dht.computeHeatIndex(f, h);
// Compute heat index in Celsius (isFahreheit = false)
float hic = dht.computeHeatIndex(t, h, false);

char buffer[10];
dtostrf(t,0, 0, buffer);
client.publish("openhab/himitsu/temperature",buffer);
//Serial.println(buffer);
dtostrf(h,0, 0, buffer);
client.publish("openhab/himitsu/humidity",buffer);

//client.publish("inTopic/humidity",sprintf(buf, "%f", h));
/*Serial.print("Humidity: ");
Serial.print(h);
Serial.print(" %\t");
Serial.print("Temperature: ");
Serial.print(t);
Serial.print(" *C ");
Serial.print(f);
Serial.print(" *F\t");
Serial.print("Heat index: ");
Serial.print(hic);
Serial.print(" *C ");
Serial.print(hif);
Serial.println(" *F"); */
}