Building a simple node server. Blog post: http://nick.balestra.ch/2015/build-a-simple-api-server-with-node/

ping.js

var utils = require('../utils');

var actions = {
    'GET': function(request, response){
      utils.respond(response, 'Pong');
    }
    // 'POST': function(request, response){},
    // 'PUT': function(request, response){},
    // 'DELETE': function(request, response){},
    // 'OPTIONS': function(request, response){}
};

exports.requestHandler = utils.actionDispatcher(actions);

router.js

var url = require('url');
var utils = require('./utils');


// The routes hash maps registered endpoint URLs
// with their relative handler modules.
var routes = {
  '/ping' : require('./endPointHandlers/ping')
};

// The router module check the url of the request
// against the routes hash and route the request to its
// relative handler. If the requested endpoint
// isn't a valid registered route a 404
// reponse will be sent back instead.
module.exports = function(request, response) {
  var routeHandler = routes[url.parse(request.url).pathname];
  if (routeHandler){
    routeHandler.requestHandler(request, response);
  } else {
    utils.respond(response, 'Oups', 404);
  }
};

server.js

var http = require('http');
var router = require('./router');

var port = 3000;
var ip = '127.0.0.1';

var server = http.createServer(router);
server.listen(port, ip);

utils.js

var headers = {
  "access-control-allow-origin": "*",
  "access-control-allow-methods": "GET, POST, PUT, DELETE, OPTIONS",
  "access-control-allow-headers": "content-type, accept",
  "access-control-max-age": 10, // Seconds.
  'Content-Type': "application/json"
};

exports.respond = function(response, data, statusCode){
  statusCode = statusCode || 200;
  response.writeHead(statusCode, headers);
  response.end(JSON.stringify(data));
};

exports.fetchData = function(request, callback){
  var data = "";
  request.on('data', function(chunk){
    data += chunk;
  });
  request.on('end', function(){
    callback(JSON.parse(data));
  });
};

exports.actionDispatcher = function(actionsHash){
  return function(request, response) {
    var action = actionsHash[request.method];
    if (action) {
      action(request, response);
    } else {
      exports.respond(response, '', 404);
    }
  }
};