SSL Certificate in express app

certificate.js

const https = require("https");
const fs = require("fs");
const express = require("express");

// read keys
const key = fs.readFileSync("localhost.key");
const cert = fs.readFileSync("localhost.crt");

// create express app
const app = express();

// create a HTTPS server
const server = https.createServer({ key, cert }, app);

// add test route
app.get("/", (req, res) => {
  res.send("this is an secure server");
});

// start server on port 8000
server.listen(8000, () => {
  console.log("listening on 8000");
});