temp2mqtt.ino

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

#define DHTPIN 2
#define DHTTYPE DHT22

const char* ssid     = "ssid";
const char* password = "password";
const char* mqtt = "ip of your hass.io server";


DHT dht(DHTPIN, DHTTYPE);
SimpleTimer timer;

WiFiClient espClient;
PubSubClient client(espClient);

void reconnect() {
  // Loop until we're reconnected
  while (!client.connected()) {
    Serial.print("Attempting MQTT connection...");
    // Attempt to connect
    if (client.connect("ESP8266 Client")) {
      Serial.println("connected");
    } 
    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(115200);
  dht.begin();
  
  delay(500);
 
  // We start by connecting to a WiFi network
  Serial.println();
  Serial.println();
  Serial.print("Connecting to ");
  Serial.println(ssid);
  
  WiFi.begin(ssid, password);
  
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
 
  Serial.println("");
  Serial.println("WiFi connected");  
  Serial.print("IP address: ");
  Serial.println(WiFi.localIP());
  Serial.print("Netmask: ");
  Serial.println(WiFi.subnetMask());
  Serial.print("Gateway: ");
  Serial.println(WiFi.gatewayIP());

  client.setServer(mqtt, 1883);
  reconnect();
  timer.setInterval(120000, getTemperature);
  getTemperature();

}

void getTemperature() {
  float f = dht.readTemperature(true);
  float h = dht.readHumidity();
  Serial.print("Temperature: ");
  Serial.print(f);
  Serial.print(", Humidity: ");
  Serial.println(h);
  String tempString = String(f, 0);
  String humidityString = String(h, 0);
  client.publish("home/office/temperature", tempString.c_str(), 2);
  client.publish("home/office/humidity", humidityString.c_str(), 2);
}

void loop() {
  if (!client.connected()) {
    reconnect();
  }
  client.loop();
  timer.run();
  
}