Adafruit_MQTT_Lib_code.ino

#include <ESP8266WiFi.h>
#include "Adafruit_MQTT.h"
#include "Adafruit_MQTT_Client.h"
/************************* WiFi Access Point *********************************/
#define WLAN_SSID       "WiFi Name"
#define WLAN_PASS       "password"
/************************* Adafruit.io Setup *********************************/
#define AIO_SERVER      "io.adafruit.com"
#define AIO_SERVERPORT  1883                   // use 8883 for SSL
#define AIO_USERNAME    "Adafruit Username"
#define AIO_KEY         "Token"

/************ Global State (you don't need to change this!) ******************/
// Create an ESP8266 WiFiClient class to connect to the MQTT server.
WiFiClient client;
// or... use WiFiFlientSecure for SSL
//WiFiClientSecure client;

// Setup the MQTT client class by passing in the WiFi client and MQTT server and login details.
Adafruit_MQTT_Client mqtt(&client, AIO_SERVER, AIO_SERVERPORT, AIO_USERNAME, AIO_KEY);
/****************************** Feeds ***************************************/
Adafruit_MQTT_Subscribe onoff = Adafruit_MQTT_Subscribe(&mqtt, AIO_USERNAME "/feeds/onoff"); //change every onoff to ur feedname on adafruit
/*************************** Sketch Code ************************************/
void MQTT_connect();
void setup() {
  Serial.begin(115200);
  delay(10);
  pinMode(D4,OUTPUT); //change pinMode acc to ur board
  Serial.println(F("Adafruit MQTT demo"));
  // Connect to WiFi access point.
  Serial.println(); Serial.println();
  Serial.print("Connecting to ");
  Serial.println(WLAN_SSID);
  WiFi.begin(WLAN_SSID, WLAN_PASS); 
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
//  Serial.println();
//  Serial.println("WiFi connected");
//  Serial.println("IP address: "); Serial.println(WiFi.localIP());
  // Setup MQTT subscription for onoff feed.
  mqtt.subscribe(&onoff);
}
void loop() {
  // Ensure the connection to the MQTT server is alive (this will make the first
  // connection and automatically reconnect when disconnected).  See the MQTT_connect
  // function definition further below.
  MQTT_connect();
  Adafruit_MQTT_Subscribe *subscription;
  while ((subscription = mqtt.readSubscription(5000))) {
    if (subscription == &onoff) {
      Serial.print(F("Got: "));
      Serial.println((char *)onoff.lastread);
      uint16_t num=atoi((char *)onoff.lastread);   
      digitalWrite(D4,!num);}
  }
}
void MQTT_connect() {
  int8_t ret;

  // Stop if already connected.
  if (mqtt.connected()) {
    return;
  }

  Serial.print("Connecting to MQTT... ");
  uint8_t retries = 3;
  while ((ret = mqtt.connect()) != 0) { // connect will return 0 for connected
       Serial.println(mqtt.connectErrorString(ret));
       Serial.println("Retrying MQTT connection in 5 seconds...");
       mqtt.disconnect();
       delay(5000);  // wait 5 seconds
       retries--;
       if (retries == 0) {
         // basically die and wait for WDT to reset me
         while (1);
       }
  }
  Serial.println("MQTT Connected!");
}