ExpressJS + Socket.IO Routing

Question

Repeated Question, But i found no perfect answer as a solutions. Please help me to solve this issue.

My App.js

   var routes = require('./routes/index');
   var users = require('./routes/users');
   var media = require('./routes/media');
   var widget = require('./routes/widget');
   var display = require('./routes/displays');
   var device = require('./routes/deviceinfo');

   app.use('/', routes);
   app.use('/display', display);


   var server = http.createServer(app);
   var io = require('socket.io')(server);
   io.set('transports', ['polling', 'websocket']);

Display Routes: "routes/display.js"

I have code to insert a display, As soon a display is created an event should emit to the list of devices.

Emit should need to write in save success callback Method.

      var express = require('express');
      var router = express.Router(); 
      router.post('/save', action_save_displays);
      function action_save_displays(req, res){
        display.save(req,body , function(err , display){
               if(!err){
                res.json(display);
                 //io.sockets.emit("displaycreated", display);
              }
        })
      }
       module.exports = routes;

How to pass io.sockets.emit in routes/display.js file. really appreciate your guidance. how to send socket object to routes to enable emit event.

Answer 1

You can swap the requires around a bit, and just pass socket.io to the display.js file

var routes  = require('./routes/index');
var users   = require('./routes/users');
var media   = require('./routes/media');
var widget  = require('./routes/widget');

var server  = http.createServer(app);
var io      = require('socket.io')(server);
var display = require('./routes/displays')(io); // here

var device  = require('./routes/deviceinfo');

app.use('/', routes);
app.use('/display', display);

io.set('transports', ['polling', 'websocket']);

and get it in the display.js file

 var express = require('express');
 var router = express.Router(); 

 module.exports = function(io) {

     router.post('/save', function(req, res) {
         display.save(req.body , function(err, display){
             if(!err){
                 res.json(display);
                 io.sockets.emit("displaycreated", display);
              }
         });
     });

    return router;
}