我在我的节点项目中使用socket.io并想知道如何导出io变量
这是我到目前为止所做的,但是我收到了这个错误:Object #<Object> has no method 'on'
:
var express = require('express');
var path = require('path');
var favicon = require('serve-favicon');
var logger = require('morgan');
var cookieParser = require('cookie-parser');
var bodyParser = require('body-parser');
var routes = require('./routes/index')(io);
var users = require('./routes/user');
var app = require('express')();
var server = require('http').Server(app);
var io = require('socket.io')(server);
server.listen(4000);
require('./routes/index')(io);
// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'jade');
// app.use(favicon(__dirname + '/public/img/favicon.ico'));
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({
extended: true
}));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));
app.use('/', routes);
app.use('/users', users);
/// catch 404 and forward to error handler
app.use(function(req, res, next) {
var err = new Error('Not Found');
err.status = 404;
next(err);
});
/// error handlers
// development error handler
// will print stacktrace
if (app.get('env') === 'development') {
app.use(function(err, req, res, next) {
res.status(err.status || 500);
res.render('error', {
message: err.message,
error: err,
title: 'error'
});
});
}
// production error handler
// no stacktraces leaked to user
app.use(function(err, req, res, next) {
res.status(err.status || 500);
res.render('error', {
message: err.message,
error: {},
title: 'error'
});
});
/*
io.on('connection', function (socket) {
socket.emit('news', { hello: 'world' });
socket.on('my other event', function (data) {
console.log(data);
});
});
*/
module.exports = app;
index.js中的
var io = require('../app');
io.on('connection', function (socket) {
socket.emit('news', { hello: 'world' });
socket.on('my other event', function (data) {
console.log(data);
});
});
我想导出变量的原因是我不必定义io就像我在app.js中所做的那样是index.js,这导致我基本上定义了服务器和app变量!
我只想在index.js路由中执行所有socket.io内容(除了必须重新定义index.js中的app,server和io变量)!
希望我已经解释了我的自我
谢谢!
答案 0 :(得分:9)
您的依赖项未正确设置。您正在初始化io之前执行index.js
var routes = require('./routes/index');
/* index.js starts being executed at this point
* hence, io is undefined inside index.js
*/
相反,为什么不尝试
<强> app.js 强>
var app = require('express')();
var server = require('http').Server(app);
var io = require('socket.io')(server);
server.listen(4000);
module.exports = io;
var routes = require('./routes/index');
var users = require('./routes/user');
<强> index.js 强>
var io = require('../app');
io.on('connection', function (socket) {
socket.emit('news', { hello: 'world' });
socket.on('my other event', function (data) {
console.log(data);
});
});
答案 1 :(得分:1)
我认为你需要使用套接字。
io.sockets.on('connection', ... );
答案 2 :(得分:0)
它看起来像一个循环依赖(app.js需要index.js和index.js需要app.js)
试试这个。
将app.js更改为:
var express = require('express');
var path = require('path');
var favicon = require('serve-favicon');
var logger = require('morgan');
var cookieParser = require('cookie-parser');
var bodyParser = require('body-parser');
var users = require('./routes/user');
var app = require('express')();
var server = require('http').Server(app);
var io = require('socket.io')(server);
server.listen(4000);
require('./routes/index')(io);
// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'jade');
// app.use(favicon(__dirname + '/public/img/favicon.ico'));
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({
extended: true
}));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));
app.use('/users', users);
/// catch 404 and forward to error handler
app.use(function(req, res, next) {
var err = new Error('Not Found');
err.status = 404;
next(err);
});
/// error handlers
// development error handler
// will print stacktrace
if (app.get('env') === 'development') {
app.use(function(err, req, res, next) {
res.status(err.status || 500);
res.render('error', {
message: err.message,
error: err,
title: 'error'
});
});
}
// production error handler
// no stacktraces leaked to user
app.use(function(err, req, res, next) {
res.status(err.status || 500);
res.render('error', {
message: err.message,
error: {},
title: 'error'
});
});
/*
io.on('connection', function (socket) {
socket.emit('news', { hello: 'world' });
socket.on('my other event', function (data) {
console.log(data);
});
});
*/
module.exports = app;
将index.js更改为:
module.exports = function(io){
io.on('connection', function (socket) {
socket.emit('news', { hello: 'world' });
socket.on('my other event', function (data) {
console.log(data);
});
});
}