Switch to Koa, more es6

routes/itunes-proxy.js

@@ -1,14 +1,14 @@
-"use strict";
-var parse = require("url").parse;
-var request = require("superagent");
+import {parse} from 'url';
+import request from 'superagent';
 
-module.exports = function(req, res) {
-  var url = "http://" + req.url.substr(8);
-  var parsed = parse(url);
+module.exports = function* (next) {
+  let url = 'http://' + this.request.url.substr(8);
+  let parsed = parse(url);
   if (parsed.host.match(/mzstatic\.com/)) {
-    request.get(url, function(response){
-      res.set(response.headers);
-      res.send(response.body);
-    });
+    let proxyResponse = yield request.get(url);
+    this.set(proxyResponse.headers);
+    this.body = proxyResponse.body;
+  } else {
+    yield next;
   }
 };