模块化Express / Socket.io应用程序

I want to be able to load these 4 functions: returnAvailable, processMessage, removeUser and joinRoom from an external file, but i get reference errors where it says that socket and nicknames are undefined. How do I modularize my app with respect to dependencies I use?

我希望能够从外部文件加载这4个函数:returnAvailable,processMessage,removeUser和joinRoom,但我得到引用错误,其中它表示套接字和昵称未定义。如何根据我使用的依赖关系模块化我的应用程序?

Here's my code:

这是我的代码:

server.js

var express = require('express');
var app = express();
var server = require('http').createServer(app);
var io = require('socket.io').listen(server);

// mongoDB init
var mongoose = require('mongoose');
mongoose.connect("mongodb://localhost:27017/chat");
var Message = require('./server/datasets/message');

//include these 4 functions
var util = require('./server/util/util');

//object which contains all users and chatrooms
var nicknames = {
    'Music': [], 
    'Videogames': [], 
    'Sports': [], 
    'TV': [],
    'Politics': []
};

// middleware
// serves static files
app.use('/client', express.static(__dirname + '/client'));
app.use('/node_modules', express.static(__dirname + '/node_modules'));


// routes
app.get('/', function(req, res){
    res.sendFile(__dirname + '/index.html')
});

app.get('/api/rooms/get', function(req, res){
    res.json(nicknames);
});


server.listen(2000);


// socket functionality
io.sockets.on('connection', function(socket){

    socket.on('new user', util.returnAvailable);

    // do when 'send message' data is received from client
    socket.on('send message', function(data){
        util.processMessage(data);
    });

    // do when 'disconnect' data is received from the client
    socket.on('disconnect', function(data){
        util.removeUser();
    });

    socket.on('leave room', function(){
        util.removeUser();
    });

});

util.js

module.exports.returnAvailable = function (data, callback){
    console.log(data);

    if(nicknames[data.room].indexOf(data.username) != -1){
        callback({ bool: false });
    }else {
        socket.nickname = data.username;
        joinRoom(socket, data.room);

        nicknames[data.room].push(socket.nickname);
        console.log(nicknames[data.room]);

        io.sockets.to(data.room).emit('usernames', nicknames[data.room]);
        callback({ bool: true, nickname: socket.nickname});
    }
}

module.exports.removeUser = function(){
    //console.log(socket.nickname + " disconnected. Bool value: " + socket.nickname==true);
    if(socket.nickname==false) return;
    // socket.room has to be defined, otherwise crashes if user reloads while not in a roomn
    if(socket.room)
    {
        nicknames[socket.room].splice(nicknames[socket.room].indexOf(socket.nickname), 1);
        socket.leave(socket.room);
    }

    io.sockets.to(socket.room).emit('usernames', nicknames[socket.room]);
}

module.exports.joinRoom = function (data){
    socket.join(data);
    socket.room = data;
    console.log(socket.room);

    var query = Message.find({room: socket.room});
    query.sort({created:-1}).limit(5).exec(function(err, results){
        if(err) { console.log(err); }

        else if(results){ 
            io.sockets.to(socket.room).emit('old messages', results); 
        }
    });
}


module.exports.processMessage = function(data){
    io.sockets.to(socket.room).emit('new message', {msg : data, nick : socket.nickname});
    var message = new Message({
        created: new Date,
        user: socket.nickname,
        message: data,
        room: socket.room
    });

    message.save(function(err){
        if(err){
            console.log(err);
        }else{
            console.log('Successfully saved.');
        }
    });
}

I'm using Express 4.13.4

我正在使用Express 4.13.4

1 个解决方案

#1

The socket variable is only available within io.sockets.on('connection', callback function so you can't use it in other files this easily. But you can pass the socket variable to the function where you are trying to use it like this

套接字变量仅在io.sockets.on('connection',回调函数中可用,因此您不能在其他文件中轻松使用它。但是您可以将套接字变量传递给您尝试使用它的函数,如这个

util.removeUser(socket);

and change the definition of removeUser to accept the socket as an argument

并更改removeUser的定义以接受套接字作为参数

module.exports.removeUser = function(socket){

    // your code here

}

The same goes for nicknames variable, use it like this

昵称变量也是如此,像这样使用它

socket.on('new user', function(data) {

    util.returnAvailable(io, socket, nicknames, data);

});

and change the function to accept those arguments

并更改函数以接受这些参数

module.exports.returnAvailable = function (io, socket, nicknames, data){

    // your code here

}