Simple Express.js Application

app_express.js

var express = require('express');
var port = 3000;

var app = express();

app.get('/', function(req, res) {
    res.send('<h1>Welcome! </h1>');
});

app.get('/username/:user_name', function(req, res) {
    res.status(200);
    res.set('Content-type', 'text/html');
    res.send('<h1>Hello, ' + req.params.user_name + '!</h1>');
});

app.listen(port, function() {
    console.log("Server is running: http://localhost:%s", port);
});

package.json

{
  "name": "simple_ws",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "",
  "license": "MIT",
  "dependencies": {
    "express": "^4.16.4"
  }
}