"TypeError:无法读取属性'apply'of undefined"

glo*_*log 10 javascript node.js express angularjs

使用node,express,socket.io,jade和angular.得到错误:TypeError: Cannot read property 'apply' of undefined.有什么建议?

index.js:

module.exports = function(app, res) {
  res.render('index', { title: 'Express' });
  var io = app.get('io');
  io.on('connection', function(socket){
  });
};
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index.jade:

extends layout

block content

script.
    var app = angular.module('hackigur', []);
    var socket = io.connect();
    var refreshTimer = 10;

    app.controller('UpdateController', function($scope){
        //socket.on('update', function(msg){
            //$scope.refreshTimer = msg;
            //$scope.$apply();
        //});

        setInterval(secondTick,1000);

        function secondTick() {
            if(refreshTimer != 0) {
                refreshTimer -= 1;
            }
            $scope.refreshTimer = refreshTimer;
            $scope.$apply();
        };
    });

h1= title
p Welcome to #{title}

div(ng-controller="UpdateController")
    p(ng-bind="refreshTimer")
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layout.jade:

doctype html
html(ng-app="hackigur")
  head
    title= title
    script(src = "/socket.io/socket.io.js")
    script(src = "/js/angular/angular.min.js")
  body
    block content

完整错误:

Server listening on port 3000
TypeError: Cannot read property 'apply' of undefined
    at Server.(anonymous function) [as on] (D:\Projects\hackigur\node_modules\so
cket.io\lib\index.js:364:15)
    at module.exports (D:\Projects\hackigur\server\api\index.js:30:8) at ...

glo*_*log 8

router该打电话给我index.js传递appmodule.export是这样的:

module.export = function (app) {
    app.get( ... , function(..., res) { 
        require(index.js)(app)(res);
};
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我需要app为我的外部声明一个变量module.export:

var x;
module.export = function (app) {
    x = app;
        app.get( ... , function(..., res) { 
        require(index.js)(x)(res);
};
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不完全理解它为什么起作用,但似乎通过应用上述内容传递了正确的app对象app.get.