Quick and dirty way to check if a website is gzipped

gistfile1.js

#!/usr/bin/env node

/**
 *  Quick and dirty way to check if a website is gzipped 
 *  Usage:  
 *     ./isgzipped www.xxx.com
 */

var exec = require('child_process').exec
  , site = process.argv[2];

if (site === undefined) {
  console.log('missing website name.');
  return;
}

exec('curl '+site+' --silent -H "Accept-Encoding: gzip,deflate" --write-out "%{size_download}" --output /dev/null', function(err, a) {
  if (err) throw err;
  exec('curl '+site+' --silent --write-out "%{size_download}" --output /dev/null', function(err, b) {
    if (err) throw err;
    console.log( a !== b);
  });
});