Intrinsic Node.js HTTP server taking into consideration IPv6 address (::)

server.js

const http = require('http');

const hostname = '127.0.0.1';
const port = 3000;

const server = http.createServer((req, res) => {
  res.statusCode = 200;
  res.setHeader('Content-Type', 'text/plain');
  res.end('Hello World\n');
});

server.listen(port, hostname, () => {
  const address = server.address()

  // If host is omitted, the server will accept connections on the unspecified IPv6 address (::) when IPv6 is available, or the unspecified IPv4 address (0.0.0.0) otherwise.
  // https://nodejs.org/api/net.html#net_server_listen_port_host_backlog_callback
  const host = (address.family === 'IPv6')
    ? `[${address.address}]:${address.port}`
    : `${address.address}:${address.port}`

  const url = `http://${host}`

  console.log(`Server running at ${url}`);
});