https://console.firebase.google.com/

建立好firbase專案後，在左側專案設定>服務帳戶 點選產生 產生新的私密金鑰

將得到的直存入.env中

// firbase.js
const dotenv = require('dotenv');
dotenv.config({ path: './config.env' });
const admin = require("firebase-admin");
const config = {
  type: process.env.FIREBASE_TYPE,
  project_id: process.env.FIREBASE_PROJECT_ID,
  private_key_id: process.env.FIREBASE_PRIVATE_KEY_ID,
  private_key: process.env.FIREBASE_PRIVATE_KEY.replace(/\\\\n/g, '\\n'),
  client_email: process.env.FIREBASE_CLIENT_EMAIL,
  client_id: process.env.FIREBASE_CLIENT_ID,
  auth_uri: process.env.FIREBASE_AUTH_URI,
  token_uri: process.env.FIREBASE_TOKEN_URI,
  auth_provider_X509_cert_url: process.env.FIREBASE_AUTH_PROVIDER_X509_CERT_URL,
  client_x509_cert_url: process.env.FIREBASE_CLIENT_X509_CERT_URL,
};

admin.initializeApp({
    credential: admin.credential.cert(config),
    storageBucket: `${process.env.FIREBASE_PROJECT_ID}.appspot.com`,
});

module.exports = admin;