Caching thingymagic

cache.js

const app   = require('express')();
const fetch = require('node-fetch');
const port  = parseInt(process.env.PORT || '8080');

const cache = {};

app.get('/:packageName', async function(req, res) {
  const now = Date.now();

  if (cache[req.params.packageName] && (cache[req.params.packageName].exp > now)) {
    const cacheData = cache[req.params.packageName].data;
    res.send(`Current version: ${cacheData.name}`);
    return;
  }

  const response = await fetch('https://api.github.com/.......', {
    headers: {
      Authorization: '...',
    }
  });

  const responseData = await response.json();
  cache[req.params.packageName] = {
    exp : now + (3600 * 1000),
    data: responseData,
  };

  res.send(`Current version: ${responseData.name}`);
});

app.listen(port, function(err) {
  if (err) throw err;
  console.log(`Server listening on :${port}`);
});