index.js

// index.js
// where your node app starts

// init project
var express = require('express');
var app = express();

// enable CORS (https://en.wikipedia.org/wiki/Cross-origin_resource_sharing)
// so that your API is remotely testable by FCC 
var cors = require('cors');
app.use(cors({ optionsSuccessStatus: 200 }));  // some legacy browsers choke on 204

// http://expressjs.com/en/starter/static-files.html
app.use(express.static('public'));

// http://expressjs.com/en/starter/basic-routing.html
app.get("/", function (req, res) {
  res.sendFile(__dirname + '/views/index.html');
});


// your first API endpoint... 
app.get("/api", function (req, res) {
  res.json({
    unix: new Date().getTime(),
    utc: new Date().toUTCString()
  });
});

app.get("/api/:timestamp", (req, res) => {
  let timestamp = req.params.timestamp;

  if (timestamp.match(/\d{5,}/)) {
    timestamp = Number(timestamp);
  }

  let date = new Date(timestamp);

  if (date.toUTCString() == "Invalid Date") {
    res.json({ error: date.toUTCString() });
  }

  res.json(
    {
    unix: date.valueOf(),
    utc: date.toUTCString()
    }
  );

});

// listen for requests :)
var listener = app.listen(8080, function () {
  console.log('Your app is listening on port ' + 8080);
});