node.js – 无法连接到Xcode中的本地服务器

Alamofire.request(.GET,"http://localhost:3000",parameters: ["code": "123"]).responseJSON {
                response in
                print ("Hello",response)
            }

我在iOS设备上运行时收到Xcode中的以下错误.

FAILURE: Error Domain=NSURLErrorDomain Code=-1004 "Could not connect to the server." UserInfo={NSUnderlyingError=0x13d84f7f0 {Error Domain=kCFErrorDomainCFNetwork Code=-1004 "(null)" UserInfo={_kCFStreamErrorCodeKey=61,_kCFStreamErrorDomainKey=1}},NSErrorFailingURLStringKey=http://localhost:3000/,NSErrorFailingURLKey=http://localhost:3000/,_kCFStreamErrorDomainKey=1,_kCFStreamErrorCodeKey=61,NSLocalizedDescription=Could not connect to the server.}

我知道当地正在服役.当我在命令行上调用以下函数时：

$node index.js
Running at http://localhost:3000

在浏览器中显示以下内容：

Cannot GET /

我的.js文件如下：

var buffer = require('buffer');
 var bodyParser = require('body-parser');
 var crypto = require('crypto');
 var express = require('express');
 var request = require('request');
 var url = require('url');
 var app = express();

var config = {
  clientId: '',clientSecret: '',callbackUrl: '',encryptionSecret: '',endpoint: 'https://accounts.spotify.com',};

 var secretString = config.clientId + ':' + config.clientSecret;
 var authHeader = 'Basic ' + new  buffer.Buffer(secretString).toString('base64');

 // app.use(bodyParser.urlencoded({ extended: false })); // TODO - Figure out why this should be here
 app.use(bodyParser.json()); // TODO - Figure out why this should be here

 var server = app.listen(3000,function() {
  var address = server.address();

  console.log('Running at http://localhost:%s',address.port);
 });

 app.post('/swap',function(req,res) {

  console.log(req.body);

  if (!req.body || !req.body.hasOwnProperty('code')) {
    console.log('Swap: missing auth code');
    res.status(550).send('Permission Denied');

    return;
  }

  formData = {
    grant_type: 'authorization_code',redirect_uri: config.callbackUrl,code: req.body.code
  };

  console.log('Swap: POST to %s',url.resolve(config.endpoint,'/api/token'),formData);

  request.post({
    url: url.resolve(config.endpoint,headers: {
      'Authorization': authHeader,'Content-Type': 'application/x-www-form-urlencoded',},form: formData,function(error,response,body) {

  if (error) {
     console.log('Swap: Error - ',error);
     res.status(500).send('Internal Server Error');

     return;
   }

    if (res.statusCode != 200) {
     debug('Swap: response: ',response.statusCode);
     res.status(550).send('Permission Denied');

    return;
    }

   var tokenData = JSON.parse(body);

   console.log('Swap: tokenData - ',tokenData);

   res.status(200).set({
     'Content-Type': 'application/json',}).send(tokenData);

 });

});