在 expressjs 路由中使用 socket.io 而不是在主 server.js 文件中 [英] Use socket.io in expressjs routes instead of in main server.js file

问题描述

我有 express/nodejs api.我正在向它添加 socket.io 功能.目前我所有的路由都在单独的文件夹中，我将它们包含在 server.js 文件中并将它们用作 app.use() 函数.

I have express/nodejs api. I am adding socket.io feature to it. Currently all of my routes are in separate folders and I include them in server.js file and use them as app.use() function.

在 server.js 文件中，我还通过侦听特定端口(例如 3000)来启动 express 服务器，如下所示.

In server.js file, I also start the express server by listening to a particular port such as 3000 as below.

let server = app.listen(3000);

根据所有谷歌搜索，我发现我需要传递服务器变量来初始化 socket.io，如下所示.

According to all google searches what I found is that I need to pass server variable to initialize socket.io like following.

let io = require('socket.io')(server);

现在的问题是，既然它需要这个变量，那么我如何在不同文件夹中的路由文件中使用 socket.io 来从客户端发出和接收事件?

Now the question is that since it needs this variable then how can I use socket.io in my routes files which are in different folder to emit and receive events from client?

更新

在 server.js 文件中

in server.js file

let route = require('./routes/route');

let app = express();

let server = app.listen(3000);

console.log('Listening to port');

let io = require('socket.io')(server);

app.use('/api/1.0/events', route(io));

在 route.js 文件中

in route.js file

let express = require('express');

module.exports = (io) => {
    console.log('IO: ', io);
};

更新 2

server.js 文件

server.js file

let express = require('express');
let events = require('./routes/events');
let app = express();
let server = app.listen(3000);

let io = require('socket.io')(server);


app.use(function(request, response, next) {
    request.io = io;
    next();
});

app.use('/events', events);

events.js 文件

events.js file

let express = require('express');

let Events = require('../models/events');

apiRoutes.post('/new', function(request, response) {
    let newEvent = new Events(request.body);

    newEvent.save((error, result) => {
        if (error) {
            response.json(error);
        } else {
            // console.log('ELSE');
            // request.io.on('connect', socket => {
                // console.log('LISTENING TO SOCKET...');

                request.io.on('EventCreated', data => {
                    console.log('DATA ON Server: ', data);
                });
            // });

            response.json({
                success: true,
                message: 'New event created'
            });
        }
    });
});

推荐答案

有多种方式可以与路由文件共享 io 变量.

There are multiple ways to share the io variable with route files.

1. 当您在路由文件中require() 时，将 io 变量作为构造函数参数传递给它.

1. When you require() in your route file, pass it the io variable as a constructor argument.

使用 app.set("io", io) 这样你就可以在任何文件中使用 let io = app.get("io")可以访问 app 对象.

Use app.set("io", io) so you can then use let io = app.get("io") in any file that has access to the app object.

创建一个中间件，将 io 对象放在每个 req 对象上，以便您可以随时从那里访问它.

Create a middleware that puts the io object on every req object so you can access it from there any time.

<小时>

以下是将其作为构造函数参数传递给路由器文件的示例:

---

Here's an example of passing it as a constructor argument to the router file:

let server = app.listen(3000);
let io = require('socket.io')(server);

// load other routers
app.use(require("./someRouterFile.js")(io));

// in someRouterFile.js
const express = require('express');

module.exports = function(io) {
    let router = express.Router()

    // define routes
    // io is available in this scope
    router.get(...)

    return router;
}

<小时>

以下是 app.set() 方案的示例:

let server = app.listen(3000);
let io = require('socket.io')(server);
app.set("io", io);

然后，在您可以访问 app 对象的路由中的任何位置，您都可以通过以下方式获取它:

Then, anywhere in your routes that you have access to the app object, you can get it with:

let io = app.get("io");

<小时>

这是使用中间件将 io 对象设置到每个 req 对象上的示例，以便它可从所有路由使用.

---

Here's an example of using a middleware to set the io object onto every req object so it's available from all routes.

let server = app.listen(3000);
let io = require('socket.io')(server);

// place this middleware before any other route definitions
// makes io available as req.io in all request handlers
app.use(function(req, res, next) {
    req.io = io;
    next();
});

// then in any express route handler, you can use req.io.emit(...)

<小时>

以下是在没有中间件的情况下将参数用于模块构造函数的示例:

---

Here's an example of using an argument to the module constructor without middleware:

// in mysocket.js
module.exports = (io) => {
    console.log('IO: ', io);
    io.on('connect', socket => {
       // handle various socket connections here
    });

    // put any other code that wants to use the io variable
    // in here


};

然后，在您的主文件中:

Then, in your main file:

let server = app.listen(3000);
let io = require('socket.io')(server);

// initialize my socketio module and pass it the io instance
require('./mysocket.js')(io);

这篇关于在 expressjs 路由中使用 socket.io 而不是在主 server.js 文件中的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！