pattern2.js

//index.js
var Project = function() {
  this.info = {};
  this.setValues = function(info) {
    for(var prop in info) {
      if(this.info[prop] !== 'undefined') {
        this.info[prop] = info[prop];
      }
    }
  };

  this.getInfo = function () {
    return this.info;
  };
}

module.exports = Project;

//app.js
var Project = require('./Project');

var webApp = new Project();
webApp.setValues({
  name: 'Twitter',
  members: 3,
  startDate: 2015
});

var mobileApp = new Project();
mobileApp.setValues({
  name: 'Facebook',
  members: 5,
  startDate: 2016
});

console.log(webApp.getInfo());
console.log(mobileApp.getInfo());
console.log(webApp.getInfo());