Firebase Admin SDK Starter

.env

FIREBASE_SERVICE_ACCOUNT_JSON={"type": "service_account","project_id": "###############","private_key_id": "################################","private_key": "-----BEGIN PRIVATE KEY-----\n##########################-----END PRIVATE KEY-----\n","client_email": "##########################","client_id": "#########################","auth_uri": "##################################","token_uri": "################################","auth_provider_x509_cert_url": "#####################","client_x509_cert_url": "###############"}
FIREBASE_REALTIME_DATABASE_URL=************************

index.js

// Add admin SDK
require("dotenv").config();
const admin = require('firebase-admin');

// Get the Service Account JSON form environment variable and convert to object
// to get the Service Account JSON file Open your project settings go to "Service Account" section
// and click on "generate new key" to get the file.
const serviceAccount = JSON.parse(process.env.FIREBASE_SERVICE_ACCOUNT_JSON);

// Initialize the SDK
admin.initializeApp({
  // Takes the credentials
  credential: admin.credential.cert(serviceAccount),
  // Database URL of realtime database (Required only if you are using realtime database)
  databaseURL: process.env.FIREBASE_REALTIME_DATABASE_URL
});
//initialization done Admin SDK ready to use!

// now get the firebase services to use it
const db = admin.firestore();
const rtdb = admin.database();