esp8266_wemos.ino

#include <FirebaseArduino.h>
#include <ESP8266WiFi.h>
// Set these to run example.
#define WIFI_SSID "YOUR_WIFI_SSID"
#define WIFI_PASSWORD "YOUR_WIFI_PASSWORD"
#define FIREBASE_DB_URL "your_firebase_url"
#define FIREBASE_DB_SECRET_KEY "your_database_secret_key"

void setup() {
  Serial.begin(115200);

  pinMode(D1, OUTPUT);
  pinMode(D2, OUTPUT);
  WiFi.begin(WIFI_SSID, WIFI_PASSWORD);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
  }
  
  Firebase.begin(FIREBASE_DB_URL, FIREBASE_DB_SECRET_KEY);
  Firebase.stream("/automation");  
}


void loop() {
  if (Firebase.failed()) {
    Serial.println("streaming error");
    Serial.println(Firebase.error());
  }
  
  if (Firebase.available()) {
     FirebaseObject event = Firebase.readEvent();
     String eventType = event.getString("type");
     eventType.toLowerCase();
     Serial.print(eventType);
     if (eventType == "put") {
      String path = event.getString("path");
      String data = event.getString("data");
      if (path.equals("/fan/value")) {
        if (data.equals("off")) {
          digitalWrite(D1, HIGH);
        } else {
          digitalWrite(D1, LOW);
        }
      } else if (path.equals("/light/value")) {
        if (data.equals("off")) {
          digitalWrite(D2, HIGH);
        } else {
          digitalWrite(D2, LOW);
        }
      }
     }
  }   
}