Bake and Unbake Node app for Open Badges

bakery_web.js

var express = require('express');
var bakery = require('openbadges-bakery');
var request = require("request");
var http = require("http");
var Stream = require('stream').Transform;
var Q = require("q");

var app = express();

function getJson(url) {
  var deferred = Q.defer();
  request(url, function(err, res, body) { 
    deferred.resolve(JSON.parse(body));
  });
  return deferred.promise;
}
function getImage(url) {
  var deferred = Q.defer();
  http.request(url, function(response) {                                        
    var data = new Stream();                                                    
    response.on('data', function(chunk) {                                       
      data.push(chunk);                                                         
    });                                                                         
    response.on('end', function() {
      var img = data.read();
      deferred.resolve(img);
    });                                                                         
  }).end();
  return deferred.promise;
}
function bake(image, assertion) {
  var deferred = Q.defer();
  bakery.bake({
      image: image,
      assertion: assertion
  }, function(err, data){
    deferred.resolve(data);
  });
  return deferred.promise;
}
function unbake(image) {
  var deferred = Q.defer();
  bakery.extract(image, function(err, json){
    deferred.resolve(json);
  });
  return deferred.promise;
}

app.get('/bake', function(req, res){
  var response = res;
  if(!req.query.assertion) {
    res.status(500).send('please add ?assertion= to bake');
    return ;
  }
  getJson(req.query.assertion).then(function(assertion) {
    getJson(assertion.badge).then(function(badge) {
      getImage(badge.image).then(function(img) {
        bake(img, assertion).then(function(img) {
          response.send(img);
        });
      });
    })
  });
});

app.get('/unbake', function(req, res){
  var response = res;
  if(!req.query.image) {
    res.status(500).send('please add ?image= to unbake');
    return ;
  }
  getImage(req.query.image).then(function(img) {
    unbake(img).then(function(json) {
          response.send(json);
        });
  });
});

app.listen(process.env.PORT || 80);