node.js - broadcast message to all the connected

Question

node.js - broadcast message to all the connected

So we have the following node.js code -

var http = require('http');

var server = http.createServer(function (request, response) {
  response.writeHead(200, {"Content-Type": "text/plain"});
  response.write("Hello World! \n");
  response.end(");
}).listen(8125);

Let's say I want to broadcast a message to all the connected users, write method of response in the createServer function doesn't do that.

So how can I broadcast message to all the connected users/clients?

There is a way doing it with pure Node.js? because I'm just learning it now, and I prefer using pure node.js for now..

javascript
ajax
node.js

Answer 1

These are HTTP requests, therefore it isn't possible. HTTP requests start on first connection and end when all the data has been sent.

In your case, the data is

response.writeHead(200, {"Content-Type": "text/plain"});
response.write("Hello World! \n");

And then connection is ended

response.end(");

If you're looking for something to keep live connections with, take a look at these:

socket.io - a realtime transport library that supports all platforms, and falls back for older software.
WebSocket-Node - a client and server websocket implementation.
Faye - publish-subscribe messaging system that uses the Bayeux protocol.

I have only used socket.io and this is how broadcasting is done.

var io = require('socket.io').listen(80);

io.sockets.on('connection', function (socket) {
  socket.broadcast.emit('user connected');
});