gzip.js

'use strict';

var express = require('express');
var compression = require('compression');
var app = express();

var oneYear;

// gzip the static resources before seding to browser, if the browser supports gzip compression 
// Verification : Observe the response header Content-Encoding: gzip

app.use(compression());

// Serves the static resources from public by mounting the path '/'. 
// Caches the static files for a year.
// Verification : 
// 1. Requesting the page for the first time should have 200 response 
// 2. Requesting the page for again by doing the refresh (ctrl + R) should have 304 response
// 3. Requesting the page again by doing the hard refresh (ctrl + shift + R) should have 200 response

oneYear = 1 * 365 * 24 * 60 * 60 * 1000;
app.use('/', express.static(__dirname + '/public/', { maxAge: oneYear }));

package.json

{
  "name": "gzipdemo",
  "version": "0.0.1",
  "main": "server.js",
  "dependencies": {
    "express": "^4.4.5"
  },
  "devDependencies": {
    "compression": "^1.6.0"
  }
}