Socket.io 从 Express 控制器发出 [英] Socket.io emit from Express controllers

问题描述

我对 Node.js/Express 很陌生，我将它用作 AngularJS 应用程序的后端.我在 StackOverflow 上到处寻找有关我的问题的帮助，但我似乎无法弄清楚如何将这些建议移植到我的代码中.

I'm quite new to Node.js / Express, and I'm using it as a backend for an AngularJS app. I've looked all over StackOverflow for some help on my problem, but I can't seem to figure out how to port the suggestions to my code.

我的应用程序如下:

• 长时间运行的 Scala 进程会定期发送我的 Node.js 应用程序日志消息.它通过发布到 HTTP API 来做到这一点
• 收到帖子后，我的应用程序将日志消息写入 MongoDB
• 然后将日志消息实时发送到 Angular 客户端.

我遇到了 Node 模块的问题，因为我不知道如何引用 Express 控制器中的套接字实例.

I am having a problem with Node's modules, as I can't figure out how to refer to the socket instance in the Express controller.

如你所见，在 server.js 中，socket.io 在那里被实例化.但是，我希望控制器本身，logs.js，能够使用 socket.io 实例发出.

As you can see, in server.js, socket.io is instantiated there. However, I would like the controller itself, logs.js, to be able to emit using the socket.io instance.

如何在控制器中引用io?我不确定如何将 io 实例传递给控制器​​以便我可以发出消息?

这里是一些节点代码:

server.js

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

require('./lib/config/express')(app);
require('./lib/routes')(app);

server.listen(config.port, config.ip, function() {
  console.log('Express server listening on %s:%d, in %s mode', config.ip, config.port, app.get('env'));
});

io.set('log level', 1); // reduce logging

io.sockets.on('connection', function(socket) {
  console.log('socket connected');
  socket.emit('message', {
    message: 'You are connected to the backend through the socket!'
  });
});

exports = module.exports = app;

routes.js

var logs = require('./controllers/logs'),
  middleware = require('./middleware');

module.exports = function(app) {
  app.route('/logs')
    .post(logs.create);
}

logs.js

exports.create = function(req, res) {
 // write body of api request to mongodb (this is fine)
 // emit log message to angular with socket.io (how do i refer to the io instance in server.js)
};

推荐答案

您可以使用基于标准 JS 闭包的模式.logs.js 中的主要导出不是控制器函数本身，而是一个工厂函数，它将接受所有需要的依赖项，并创建控制器:

You can use a pattern based on standard JS closures. The main export in logs.js will not be the controller function itself, but a factory function that will accept all needed dependencies, and create the controller:

exports.create = function(socket) {
  return function(req, res) {
    // write body of api request to mongodb
    socket.emit();
  }
}

然后，当你想使用它时:

Then, when you want to use it:

app.route('/logs').post(logs.create(socket));

由于您在单独的包中设置了路由，因此您必须在 routes.js 中使用相同的模式 - routes 应接收套接字以用作参数.

Since you set up your routes in a separate package, you have to use the same pattern in routes.js - routes should receive the socket to use as a parameter.

如果您想稍后使用 DI 处理这些事情，或者使用模拟套接字"测试您的控制器，则此模式非常有效.

This pattern works well if you want to handle those things with DI later, or test your controllers with mock "sockets".

这篇关于Socket.io 从 Express 控制器发出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！