In one of my node.js script i am trying to use socket.io in express route. I found many similar questions and tried to implement the solution as suggested but nothing worked out. May be because of my lack of understanding of express routes. I followed below links,
How use socket.io in express routes with node.js
Use socket.io in expressjs routes instead of in main server.js file
This is my app.js
const express = require('express');
const app = express();
const server = require('http').createServer(app);
const io = require('socket.io').listen(server);
const PORT = 3000;
server.listen(PORT);
console.log('Server is running');
var api = require('./routes/api');
//app.use('/api', api);
app.use('/api', (req, res) => {
res.sendFile(__dirname + '/api.html');
});
app.get('/', (req, res) => {
res.send("this is home location");
});
And route file api.js in ./routes folder
var express = require('express');
var router = express.Router();
var fs = require("fs");
var bodyParser = require('body-parser');
const app = express();
const server = require('http').createServer(app);
const io = require('socket.io').listen(server);
console.log("inside api route");
router.get('/', function(req, res, next) {
console.log("api route called");
const connections = [];
var jsonobj = [{name:"john",score:345},{name:"paul",score:678}]
io.sockets.on('connection',(socket) => {
connections.push(socket);
console.log(' %s sockets is connected', connections.length); // this is not printing
socket.on('disconnect', () => {
connections.splice(connections.indexOf(socket), 1);
});
socket.emit('server message', jsonobj);
});
//res.send(jsonobj)
});
module.exports = router;
Socket.emit is not showing data on html page i am rendering on route use. My html code is,
//api.html
<!DOCTYPE html>
<html lang="en">
<body>
<div class="container">
<h1 class="jumbotron">
Node js Socket io with socket route example
</h1>
<div class="results">results</div>
</div>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/socket.io/2.0.4/socket.io.js"></script>
<script>
jQuery(document).ready(function() {
var socket = io.connect();
var jsondata = "";
socket.on('server message', function(data){
console.log('got data from server',data)
jsondata = JSON.stringify(data);
//console.log('jsondata',jsondata)
$('.results').html(jsondata);
});
});
</script>
</body>
</html>
Please suggest what i am supposed to get route socket data in html page.
Thanks
Ok, let's try to understand why do you need to send data via the socket inside a route in the first place. Websockets are meant for sending data asynchronously without the client having to make a request. If the client is already making an HTTP request, then you can just send the data in the HTTP response.
Now having said there, there are clearly some use cases where you have to send data to some WebSocket channel based on the actions of some OTHER user's requests. If that is the case, there are multiple ways of doing this. One clean way would be to use an event-driven architecture.
Try something like this... find my comments inline below -
const express = require('express');
const router = express.Router();
const fs = require("fs");
const bodyParser = require('body-parser');
const app = express();
const server = require('http').createServer(app);
const io = require('socket.io').listen(server);
// move the socket connection outside of the route controller
// you must register the event listeners before anything else
const connections = [];
io.sockets.on('connection', (socket) => {
connections.push(socket);
console.log(' %s sockets is connected', connections.length); // this is not printing
socket.on('disconnect', () => {
connections.splice(connections.indexOf(socket), 1);
});
});
// Event emitter for sending and receving custom events
const EventEmitter = require('events').EventEmitter;
const myEmitter = new EventEmitter();
myEmitter.on('my-event', function (jsonobj) {
// do something here like broadcasting data to everyone
// or you can check the connection with some logic and
// only send to relevant user
connections.forEach(function(socket) {
socket.emit('server message', jsonobj);
});
});
router.get('/some-route', function (req, res, next) {
const jsonobj = [{ name: "john", score: 345 }, { name: "paul", score: 678 }]
// emit your custom event with custom data
myEmitter.emit('my-event', jsonobj);
// send the response to avoid connection timeout
res.send({ok: true});
});
module.exports = router;
At first glance, it looks like you are delcaring the URL prefix twice. Once in app.js and again in api.js.
Try localhost:port/api/api
If this is the case, change
router.get('/api', function(req, res, next){
to
router.get('/', function(req, res, next){
This will allow you to hit localhost:port/api and access your endpoint.
I am just starting to understand this myself, but I think where you are at is close.
In your app.js add to the end of the file:
const express = require('express');
const app = express();
const server = require('http').createServer(app);
const io = require('socket.io').listen(server);
const PORT = 3000;
server.listen(PORT);
console.log('Server is running');
var api = require('./routes/api');
//app.use('/api', api);
app.use('/api', (req, res) => {
res.sendFile(__dirname + '/api.html');
});
app.get('/', (req, res) => {
res.send("this is home location");
});
app.set("socketio", io); // <== this line
That stores the "io" variable in "socketio". Which you can grab in any of your other ".js" files.
var express = require('express');
var router = express.Router();
var fs = require("fs");
var bodyParser = require('body-parser');
const app = express();
const server = require('http').createServer(app);
//const io = require('socket.io').listen(server); // <== change this
const io = app.get("socketio"); // <== to this
console.log("inside api route");
router.get('/', function(req, res, next) {
console.log("api route called");
const connections = [];
var jsonobj = [{name:"john",score:345},{name:"paul",score:678}]
io.sockets.on('connection',(socket) => {
connections.push(socket);
console.log(' %s sockets is connected', connections.length); // this is not printing
socket.on('disconnect', () => {
connections.splice(connections.indexOf(socket), 1);
});
socket.emit('server message', jsonobj);
});
//res.send(jsonobj)
});
module.exports = router;
And you should do that with any other variables which are required in other ".js" files.
Also note that in your files, you are setting the variables up again. It is better to do the same as I've shown you with "io". The only variable in other files I setup is "app" itself.
Hope this helps...
You tried to create and start the servers from two different places in your single project, which is inconvenient. You just need some cleanup, that's all.
app.js
const express = require('express');
const app = express();
const server = require('http').createServer(app);
const io = require('socket.io').listen(server);
// Listen to sockets here instead of listening in routes/api.js
const connections = [];
var jsonobj = [{name:"john",score:345},{name:"paul",score:678}]
io.sockets.on('connection',(socket) => {
connections.push(socket);
console.log(' %s sockets is connected', connections.length); // this is not printing
socket.on('disconnect', () => {
connections.splice(connections.indexOf(socket), 1);
});
socket.emit('server message', jsonobj);
});
const PORT = 3000;
server.listen(PORT);
console.log('Server is running');
var api = require('./routes/api');
//app.use('/api', api);
app.use('/api', (req, res) => {
res.sendFile(__dirname + '/api.html');
});
app.get('/', (req, res) => {
res.send("this is home location");
});
routes/api.js
var express = require('express');
var router = express.Router();
var fs = require("fs");
var bodyParser = require('body-parser');
// Comment these out
// const app = express();
// const server = require('http').createServer(app);
// const io = require('socket.io').listen(server);
console.log("inside api route");
router.get('/', function(req, res, next) {
console.log("api route called");
// Comment these out
// const connections = [];
// var jsonobj = [{name:"john",score:345},{name:"paul",score:678}]
// io.sockets.on('connection',(socket) => {
// connections.push(socket);
// console.log(' %s sockets is connected', connections.length); // this is not printing
// socket.on('disconnect', () => {
// connections.splice(connections.indexOf(socket), 1);
// });
// socket.emit('server message', jsonobj);
// });
//res.send(jsonobj)
});
module.exports = router;
Leave your api.html as it is. Hope this helps.
Related
I want to add socket.io on the index and it is like this i need to figure out how to do this with this code here and i want to emit the data when a route is called in another file how can i do this? you can see i tried down the code to put the socket io but i don't know can someone help please? also this is made in the backend like this is supposed to be an API and i'll not have a front-end and that's my problem i never used socket.io like this
// all the requires
require('./models/Service');
require('./models/Activities');
const express = require('express');
const app = express();
const mongoose = require('mongoose');
const bodyParser = require('body-parser');
const cors = require('cors');
const serviceRoutes = require('./routes/serviceRoutes');
const activityRoutes = require('./routes/activitiesRoutes');
const errorHandler = require('./helpers/Error-handler');
const logger = require('./config/winston');
const http = require('http').Server(app);
// all the app use
app.use(cors());
app.use(bodyParser.urlencoded({ extended: false }));
app.use(bodyParser.json());
app.use(serviceRoutes);
app.use(activityRoutes);
app.use(errorHandler);
// this calls for the users route to authenticate
app.use('/users', require('./Users/user.controller'));
// connection to database
mongoose.connection.on('connected', () => {
console.log('Connected to mongo instance');
});
mongoose.connection.on('error', err => {
console.error('Error connecting to mongo', err);
});
// server start up
const port = process.env.NODE_ENV === 'production' ? 80 : 4000;
http.listen(port, function() {
console.log('listening on ' + port);
try {
logger.info('Server and Database is initiated');
}
catch (error) {
logger.error(error);
}
});
// implementation of io
const io = require("socket.io")(http);
io.on('connection', function(socket) {
console.log('A user connected');
socket.on('disconnect', function () {
console.log('A user disconnected');
});
});
app.get('/', function(req, res) {
res.send(console.log('hey', io))
});
module.exports = io;
You can have the socket join a room on connection and attach io to the app object with app.set('io', io). This can then be accessed in controllers with req.app.get('io'), and you can emit to specific rooms.
i'm trying to add socket.io on my already existing NodeJS API REST Project.
var express = require('express')
var bodyParser = require('body-parser');
var https = require('https');
var http = require('http');
var fs = require('fs');
var router = require('./route/router');
require('dotenv').config();
var app = express();
app.use(bodyParser.urlencoded({ extended: true }));
app.use(bodyParser.json());
app.use(require('helmet')());
app.use(function (req, res, next) {
res.setHeader('Access-Control-Allow-Origin', '*');
res.setHeader('Access-Control-Allow-Methods', 'GET,PUT,POST,DELETE,OPTIONS');
res.setHeader('Access-Control-Allow-Headers', 'Authorization,Content-Type');
next();
});
router(app);
if (process.env.PRODUCTION === "false") {
http.createServer(app).listen(8080, function() {
console.log('8080 ok');
});
var io = require('socket.io')(http);
} else {
const options = {
cert: fs.readFileSync('./../../etc/letsencrypt/live/test.com/fullchain.pem'),
key: fs.readFileSync('./../../etc/letsencrypt/live/test.com/privkey.pem')
};
https.createServer(options, app).listen(8443, function() {
console.log('8443 ok');
});
var io = require('socket.io')(https);
}
io.sockets.on('connection', socket => {
console.log('socketio connected');
});
I have no error displayed (server side). But, when I tried on client side, this.socket = io('ws://localhost:8080/');, it's not working at all.
I get GEThttp://localhost:8080/socket.io/?EIO=3&transport=polling&t=NG6_U6i [HTTP/1.1 404 Not Found 1ms] browser console.
It seems that something is not ok with the server, but I can't find what's going on
Any idea ?
Thanks
Try this way, you need to include (I don't know if this is the correct word to use) the express server into the socket.io server.
const express = require('express');
const socketio = require('socket.io');
const port = process.env.PORT || 3006;
const app = express();
const server = app.listen(port, () => {
console.log(`App started on port ${port}`)
});
const io = socketio(server, { forceNew: true });
io.on('connect', (socket) => {
// do this
// do that
});
The code above is a skeleton of how express and socket.io are used together. Please modify it as per your needs.
Good luck.
i'm little stuck on my express application.
I have a file index.js in routes folder and I want to save the result of mydata
var express = require('express');
var router = express.Router();
router.get('/', token, function(req, res, next) {
var mydata = req.userId
res.render('index', {
title: 'Welcolme',
});
});
module.exports = router;
And, in my other file (which depends on app.js), I would like to get and pass mydata to the server
var app = require('../app');
server.listen(port, function () {
require('../assets/js/server/socket')(server, mydata);
});
(Here is my app.js)
var express = require('express');
var indexRouter = require('./routes/index');
var path = require('path');
var app = express();
// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'twig');
app.use('/', indexRouter);
module.exports = app;
And the socket file
var io = {};
module.exports = (server, mydata) => {
console.log('Hello : ' , mydata)
io = require('socket.io')(server);
io.on('connection', (socket) => {
console.log('Connected')
});
};
Is there a way to do that?
Thank you :)
Maybe instead of still having this route.get('/') ...
You can let the user enter the data and have it transferred directly through the WebSocket connection.
Example:
//Client-side
//Get the user data somewhere from the HTML page
const userData = document.getElementbyId("some html element's id here").innerHTML;
//Send it to the back end
socket.emit('userData',userData)
//Open a listener to get the data from the back end later
socket.on('processedData',processedData=>{
//Use it in the way you desired.
});
//Server-side
io.on('connection', (socket) => {
console.log('Connected')
socket.on('userData',userData=>{
//Do something here, like validation and stuff
socket.emit('processedData','processedData here')
});
});
The following works fine, I can get the http response on my client app BUT the socketio emit doesn't seem to work. I have no idea why it is not firing.
Here's my code (some parts removed):
app.js
var express = require('express');
var port = process.env.PORT || 3000;
var socketio = require('socket.io');
var app = express();
var server = require('http').Server(app);
var io = socketio(server);
var beacons = require('./routes/beacons')(io);
app.use('/beacons', beacons);
server.listen(port, () => {
console.log('Listening on port '+port);
});
io.on('connection', (socket) => {
socket.on('beacon:show', function(data) {
console.log('Show beacon: ' + data)
socket.broadcast.emit('beacon:draw', data)
})
});
module.exports = app;
beacons.js
var express = require('express');
var router = express.Router();
module.exports = function(io) {
router.get('/buy', function(req, res) {
io.emit('beacon:show', {data: someData}) // Not Firing
res.json({success: true})
})
return router
}
You need to wrap your io.emit() inside an io.on('connection', => {}).
At the moment, you are sending in just the io variable, but every single request and emission needs to be wrapped inside a connection event. Otherwise how does socket.io know who it's sending it to, or if there's even anyone to send it to?
This can only really be done inside beacons.js and the router.get('/buy') section, because having it the other way around (a route wrapped inside a connection) won't work.
I have the app.js code:
var express = require('express');
var app = express();
var server = require('http').createServer(app);
var io = require('socket.io')(server);
io.on('connection', function(socket){
socket.on('newRideAdded', function(exclude){
io.emit('newRideAdded', exclude);
});
console.log('a user connected');
socket.on('disconnect', function(){
console.log('user disconnected');
});
});
var bodyParser = require('body-parser');
app.use(bodyParser.json()); // support json encoded bodies
app.use(bodyParser.urlencoded({ extended: true })); // support encoded bodies
app.use(express.static(__dirname + '/public/'));
app.use('/rides', require('./routes/rides'));
app.use('/user', require('./routes/user'));
server.listen("8080", function() {
console.log("Connected to db and listening on port 8080");
});
And I want to move the socket io code to its router's page.
That is the router page:
var express = require('express');
var router = express.Router();
var mongojs = require('mongojs');
var db = mongojs("ride4you", []);
router.post('/getRides', function(req, res, next) {
db.rides.find(function(err, docs) {
res.json(docs);
});
});
// rest of the restapi in this page.
// I want socket code to be here
module.exports = router;
As you can see i have each socket emits in each router's page and I already have module.exports in routers page.
How can it be done?
Thanks.
Using Express 4, in your app.js file you can use
app.set('socketio', io);
Then in your router or controller, you can use
router.post('/getRides', function(req, res, next) {
var io = req.app.get('socketio');
io.to(//socket.id//).emit("message", data);
db.rides.find(function(err, docs) {
res.json(docs);
});
};
This is a clean way of passing the reference along.