var request = require('request');
var zlib = require('zlib');

request(url, {encoding: null}, function(err, response, body){
  if(response.headers['content-encoding'] == 'gzip'){
    zlib.gunzip(body, function(err, dezipped) {
      callback(dezipped.toString());
    });
  } else {
    callback(body);
  }
});