Node app; Call server function from Client - ajax

I can't seem to call a server function from my client using either socket.io or an ajax call. Any help would be appreciated. For socket.io, I was trying something like this:
server (no error is being thrown, only I never see the console.log):
var app = express();
var server = require('http').Server(app);
var io = require('socket.io')(server);
var socket = io.sockets.on('connection', function(socket) {});
socket.on('admin-refresh', function() {
console.log("*** Admin refresh ***");
});
client (yes I'm including all necessary files, no error is being thrown on client side nor server):
$('document').ready(function() {
var socket = io();
$('#refresh').click(function() {
console.log('refresh clicked..');
io.emit('admin-refresh');
});
});
I don't need any data to be passed, I just want to alert the server to call a function. So perhaps an ajax call would be easier? How would I set up the server to listen for calls?

Why do you have an empty connection callback..? Look at the docs again.
var app = express();
var server = require('http').Server(app);
var io = require('socket.io')(server);
io.on('connection', function(socket) {
socket.on('admin-refresh', function() {
console.log("*** Admin refresh ***");
});
});

Related

c# SocketIoClientDotNet, node js socket.IO

c# winform tries to send node.js socket through socket.
The client is connected to server, but the socket.emit value and socket.on value do not communicate normally.
I'd like to find a solution to this.
I would like to send this name of client to the server as json type data, receive json type data from the server, read it, and send data back to json.
The data of socket.emit and socket.on are not working properly, so the code has been deleted.
c# code
private void socketLogin(string email, string pw)
{
var socket = IO.Socket("http://localhost:3000/login.html");
socket.On(Socket.EVENT_CONNECT, () =>
{
});
var loginjson = new JObject();
loginjson.Add("email", email);
loginjson.Add("password", pw);
socket.Emit("socketlogin", loginjson.ToString());
socket.On("login", (data) => {
MessageBox.Show(data.ToString());
});
}
node.js Code
var server = require('http').Server(app);
var io = require('socket.io')(server);
io.on('connection', function(socket) {
console.log('connection');
socket.on('socketlogin', function(data) {
var testLogin = { 'Login': "success" };
socket.emit('login', data);
});
});
server.listen(app.get('3000'))
in your C# you are making your socket inside a function, but at the end of the function the socket is thrown away because it is only a local variable.
There are many ways to deal with this, but essentially what you want to do is use a thread to handle the socket comms then dispatch things back to your UI thread.

Sending data received from one socket.io server to a web socket client

I'm starting to use socket.io and I have a problem that I can't solve so far
I have two nodejs running, one is the socket.io data server and the other one is going to interact with web clients
I need to get data from the server and send it to my web clients, the problem is I can't emit data to the clients outside the 'on connect'
I think is better to explain it with a simple example
const socket = require('socket.io-client')('http://localhost:12000');
const SocketIO = require('socket.io');
const app = require('../app');
const server = http.createServer(app);
server.listen(port);
// client socket, this is a regular message from
// the server running on port 12000, it works
socket.on('msg_from_server', data => {
console.log(data);
});
// server socket
const io = SocketIO(server);
io.on('connection', (s) => {
// this works
s.emit('msg_to_client', {data: 'xxxx'})
// this doesn't works
socket.on('msg_from_server', data => {
console.log(data);
});
});
socket client for server on port 12000 and socket from io.on('connection', (socket) both are different. But you are mixing them both.Do something like this:
const Socket_12000 = require('socket.io-client')('http://localhost:12000');
const SocketIO = require('socket.io');
const app = require('../app');
const server = http.createServer(app);
server.listen(port);
// client socket
socket.on('msg_from_server', data => {
console.log(data);
});
// server socket
const io = SocketIO(server);
io.on('connection', (socket) => {
// this works
socket.emit('msg_to_client', {data: 'xxxx'})
// this doesn't works
Socket_12000.on('msg_from_server', data => {
console.log(data);
});
});
I have created a basic gist depicting the problem/solution please commant if you are looking something else.
https://gist.github.com/sandeepp2016/bb1946bcbeb2f11d57bc3aa2e44c158e

Configuring socket.io on Cloud Foundry

I'm trying to set up a socket.io connection on Cloud Foundry via IBM Toolchains. I've gone through the docs and have been trying to get socket.io to connect to port 4443. I'm kind of new to this so would appreciate if you could provide some pointers on how to set up socket.io on the CF env as I still struggle to digest parts of the documentation. Code can be found below.
//---------------------------
// app.js
//---------------------------
// Start the app on cloud foundry
var express = require('express');
var app = express();
var cfenv = require('cfenv');
var appEnv = cfenv.getAppEnv();
app.use(express.static(__dirname + '/public'));
app.listen(appEnv.port, '0.0.0.0', function() {
console.log("Server is starting on " + appEnv.url);
});
// Connect socket.io
var server = require('http').Server(app);
var io = require('socket.io')(server);
var cookieParser = require('cookie-parser');
app.get('/', function (req, res) {
res.sendFile(__dirname + 'public/index.html');
});
io.on('connection', function (socket) {
console.log('a user connected');
});
var port = 4443; // Cloud Foundry assigned port for TCP/WebSocket communications
server.listen(port, function() {
console.log('listening on ', port);
});
<script src="/socket.io/socket.io.js"></script>
<script>
var socket = io.connect("https://0.0.0.0:4443");
</script>
My understanding after going through the socket.io docs is that the IP provided should be the location.hostname which I believe to be 0.0.0.0 in this case as it refers to the IP which the express instance for the app is listening on. Not too sure about this though.
By changing it to below:
<script src="https://cdnjs.cloudflare.com/ajax/libs/socket.io/2.2.0/socket.io.slim.js"></script>
<script> var socket = io(); </script>
The error changes to a 404 error with the following error being repeated: "https://realtimetrafficanalysisaks.mybluemix.net/socket.io/?EIO=3&transport=polling&t=". I've checked regarding the app and server settings but can't seem to pinpoint the error
Thanks in advance!
I didn't manage to sort this out with socket.io due to the port issue but I was able to get it running using the express-ws package

Retrieve datas from Node.js server and display it on a webpage

I'm a node.js noob and I've been stuck on this for 2 days. It seems there are basic concepts I don't seem to grasp on how node.js is working.
What I want to do:
Get a stream of informations from live Counter-Strike Global Offensive games and display them on a webpage.
The datas from the game are sent to localhost:3000. If I create a simple nodejs server and print the datas, it works.
How do I use the "body" variable from the server req into socket.io to be consumed from a client POV?
nb: this code is based on the templates provided by Webstorm.
var app = require('../app');
var debug = require('debug')('test2:server');
var http = require('http');
/**
* Get port from environment and store in Express.
*/
var port = normalizePort(process.env.PORT || '3000');
app.set('port', port);
/**
* Create HTTP server.
*/
var server = http.createServer(app);
var payload = server.on('request',function (req, res){
var body = '';
req
.on('data', function(data) {
body += data;
})
.on('end', function () {
console.log('POST payload: ' + body);
return body
})
});
/**
* Setup Socket.io
*/
var io = require('socket.io')(server);
io.on('connection', function(socket){
console.log('a user connected');
});
io.on('data', function(socket){
console.log('data incoming:\n');
// and now What? How do I listen to the datas coming from the game and not from the Express server??
socket.emit('csgo', payload);
})
/**
* Listen on provided port, on all network interfaces.
*/
server.listen(port);
server.on('error', onError);
server.on('listening', onListening);
Alright after 2 days of struggle and misunderstanding, I figured out a working solution forking the following and updating the code to make it work: https://github.com/fassn/csgoWebPanel

Socket.IO client cannot send handshake parameter

Here is my code:
var socket = require('socket.io-client')('http://127.0.0.1:3000/printers', {
query: "shop=" + "123456",
transports: ["websocket"]
});
If I delete query, I can connect to socket. Where am I wrong?
There doesn't seem to be anything wrong with your client-side code. I can connect by copying and pasting your code.
I suspect the problem is within your server-side code. Here is an example I am using with your client-side code:
var http = require('http');
var io = require('socket.io');
var server = http.createServer(function(req,res){
res.writeHead(200);
res.end('Hello, World!\n');
});
server.listen(80);
var socket = io.listen(server);
socket.use(function(socket, next){
console.log("Query: ", socket.handshake.query);
if (socket.handshake.query.shop == '123456') {
next();
}
next(new Error('You cannot use that shop'));
});
socket.on('connection', function(client) {
console.log('New Connection');
});
I'm able to obtain the query data in the 'socket.use' function. If I don't call the next() function, the client will never get the message that the server has received the response and is connected.
I recommend checking out the example used in this thread.

Resources