index.js

var ip = require('ip');
var restify = require('restify');
var pkg = require('./package.json');

var server = restify.createServer({ name: 'demo' });

var message = process.env.MESSAGE || 'Hello, world';

server.get('/', function (req, res, next) {
  res.send(200, `${message} | ${ip.address()} | Version ${pkg.version}`);
  return next();
});

server.listen(+(process.env.DEMO_API_PORT || '9000'));