server.js

var url = require('url');
var fs = require('fs');

var router = {
  "/chart.js": "/node_modules/chart.js/dist/Chart.js",
  "/bootstrap.min.css": "/node_modules/bootstrap/dist/css/bootstrap.min.css",
  "/bootstrap-theme.min.css": "/node_modules/bootstrap/dist/css/bootstrap-theme.min.css"
};

module.exports = function handler (req, res){
  var servefile = function  (err, data) {
    if (err) {
      console.log(err);
      res.writeHead(500);
      return res.end('Error loading');
    }
    res.writeHead(200);
    res.end(data);
  };

  var path = url.parse(req.url).pathname;
  if (path === '/dashboard.js' || path === '/index.html' || path === "/"){
    path = (path === '/dashboard.js') ? '/dashboard.js' : "/index.html";
    fs.readFile(__dirname + path, servefile);
  }else if (router[path] !== undefined) {
    fs.readFile(__dirname + router[path], servefile);
  }else{
    res.writeHead(404);
    res.end();
  }
};