firstly sorry for not standard English. : D
I have a chat application using nodejs, expresss finished running on port 3000. So I want to embed in website application clients, then how?
I had to use ajax load, but can not be:
jQuery.ajax({
type:"GET",
url:"http://localhost:3000/client/",
success: function (data){
jQuery('body').append(data);
}
});
Since you are using socket.io at server side then you can get its reference at the client using below line (jquery required):
$.getScript(host+'socket.io/socket.io.js', function()
{
var clientSocket = io.connect(host);
// ... do other stuff with your socket
});
Where host is your server host name e.g. http://192.168.1.5:3000/ where your nodejs application is deployed.
For more information see here for more client - server communication exposed events.
try the example from http://book.mixu.net/node/ch3.html (it uses long-polling) once done with it use socket.io
Related
I need to create a small authentication layer on top of a 3rd party web-socket based chat application. I have a simple API (get) that can validate api tokens from requests. What I want to do is essentially validate their token (which I know how to do) then proxy the websocket connection to the actual chat server.
I've been looking for solutions and this thread seems to give some pointers in the right direction however I can't get any of the solutions to work.
var http = require('http'),
WebSocket = require('faye-websocket'),
conf = require('./conf.json');
var server = http.createServer();
server.on('upgrade', function(request, socket, body) {
console.log('upgrade fired');
var frontend = new WebSocket(request, socket, body),
backend = new WebSocket.Client('ws://echo.websocket.org');
frontend.pipe(backend).pipe(frontend);
});
server.on('connection', function(socket) {
console.log('connection')
backend = new WebSocket.Client('ws://echo.websocket.org');
console.log(backend);
socket.pipe(backend).pipe(socket);
})
server.listen(conf.port);
console.log('Listening on '+port.conf);
The connection event is fired, however the upgrade event which is supposed to be fired on a ws connection never is.
The goal is to first authenticate a api key to an external server, then open a proxy to the chat websocket all through a request to this node server via a websocket connection. I'll most likely pass the api key as a get parameter for simplicity. I also looked at this package and attempted using it however it didn't work as well.
The issue ended up being with nginx. I forgot I was proxying requests through the reverse proxy and by default nginx does not support the ws:// connection so it drops it.
I am using sockets.io with nodejs server to send/receive events between client and server.It works well on local pc but the issue comes when i have to connect a remote client to it and i dont need to use frontend template file or html. In that case, how can i define io() object i.e. a socket connection because without it i cannot access my nodeserver. Currently i have created a js file on remote client and it looks like this:
`var socket=io.connect('http://a.b.c.d:3000');
var name="alice";
socket.emit('ping',(name)=>{
socket.on('pong', reply);
console.log(reply);
});`
Web Sockets work over the HTTP protocol, so you need to run a server for it.
My goal is to build a chat application - similar to whatsapp
To my understanding, socket.io is a real-time communication library written in javascript and it is very simple to use
For example
// Serverside
io.on('connection', function(socket) {
socket.on('chat', function(msg) {
io.emit('chat', msg);
});
});
// ClientSide (Using jquery)
var socket = io();
$('form').submit(function(){
socket.emit('chat', $('#m').val());
$('#m').val('');
return false;
});
socket.on('chat', function(msg){
$('#messages').append($('<li>').text(msg));
});
1) do I always need to start an io.on('connection') to use the real-time feature or i could just start using socket.on object instead? for example i have a route
app.post('/postSomething', function(req, res) {
// Do i need to start an io.on or socket.on here?
});
because i want the real-time feature to be listen only on specific route.
2) Redis is a data structure library which handles the pub/sub, why do we need to use pub/sub mechanism?
I read alot of articles but couldn't grasp the concept. Article example http://ejosh.co/de/2015/01/node-js-socket-io-and-redis-intermediate-tutorial-server-side/
for example the code below
// Do i need redis for this, if so why? is it for caching purposes?
// Where does redis fit in this code?
var redis = require("redis");
var client = redis.createClient();
io.on('connection', function(socket) {
socket.on('chat', function(msg) {
io.emit('chat', msg);
});
});
3) Just wondering why I need nginx to scale node.js application? i found this stackoverflow answer:
Strategy to implement a scalable chat server
It says something about load balancing, read that online and couldn't grasp the concept as well.
So far I have only been dealing with node.js , mongoose simple CRUD application, but I'm willing work really hard if you guys could share some of your knowledge and share some useful resources so that I could deepen my knowledge about all of these technologies.
Cheers!
Q. Socket.on without IO.on
io.on("connection" ... )
Is called when you receive a new connection. Socket.on listens to all the emits at the client side. If you want your client to act as a server for some reason then (in short) yes io.on is required
Q. Redis pub/sub vs Socket.IO
Take a look at this SO question/anwer, quoting;
Redis pub/sub is great in case all clients have direct access to redis. If you have multiple node servers, one can push a message to the others.
But if you also have clients in the browser, you need something else to push data from a server to a client, and in this case, socket.io is great.
Now, if you use socket.io with the Redis store, socket.io will use Redis pub/sub under the hood to propagate messages between servers, and servers will propagate messages to clients.
So using socket.io rooms with socket.io configured with the Redis store is probably the simplest for you.
Redis can act like a message queue if it is a requirement. Redis is a datastore support many datatypes.
Q. Why Nginx with Node.js
Node.js can work standalone but nginx is faster to server static content.
Since nginx is a reverse proxy therefore servers are configured with nginx to handle all the static data (serving static files, doing redirects, handling SSL certificates and serving error pages.
) and every other request is sent to node.js
Check this Quora post as well: Should I host a node.js project without nginx?
Quoting:
Nginx can be used to remove some load from the Node.js processes, for example, serving static files, doing redirects, handling SSL certificates and serving error pages.
You can do everything without Nginx but it means You have to code it yourself, so why not use a fast and proven solution for this.
Currently, I am implementing an API using nodejs express, then it needs to connect to socket.io and send event.
The API is located in socket.io-client (client), and it connects to socket.io (server)
1st API call: success
The connection is made for the 1st call of the API, message is sent and socket can be disconnected, with the 'disconnect' callback is invoked both on client and server side.
2nd API call: failure
When the API is invoked the 2nd time, the connection to server cannot be made, 'client' callback on client side is not called.
3rd API call: success
Then I tried to restart the client side, keeping other things unchanged. The API is called again, and the connection to socket.io is made successfully and everything is fine.
Can anyone explain the logistics behind this?
Updated
client.js
App.getByUserId(message.to_id, function(error, app) {
var socket = io.connect('http://127.0.0.1:9002');
socket.on('connect', function(){
console.log("client connect socket id:" + socket.id);
console.log("appkey:" + app.private_token);
socket.emit('appkey.check',{appkey: app.private_token, uuid: message.to_id.uuid}, function(data){
socket.emit("forceDisconnect");
socket = null;
});
});
You just hit one of Socket.IO's many "features" or "bugs" depending how you see this. Socket.IO tries to be smart and re-use connections (which causes a lot of connection issues actually) The way around this is use the force new connection option in your io.connect:
io.connect('http://127.0.0.1:9002', { 'force new connection': true });
What you could also do is use https://github.com/primus/primus which wraps Socket.IO if you use the socket.io transformer. Internally, it completely removes the use of the io.connect and uses the much more lower level io.Socket constructor to create more stable connections that you would get with a stock socket.io.
With socket 1.0+, you have to use this for forcing new connection.
io.connect(SERVER_IP, { 'forceNew': true });
There is a way to manage the socket.io creation at Server Side?, Currently, I couldn't found any doc, Only found in relation with the socket is created per request from a client "io.connect(server)".
The current flow work OK:
Set Socket.io (at Node.js) at SERVER:PORT
Client connect to SERVER
using io.connect(SERVER:PORT)
I wonder if it is possible ? Trying to do:
Set Socket.io (at Node.js) at SERVER:PORT
Recieved a POST (REST) - Server side
Create/Open Socket.io a server side.
At response of Post send the id?
the clien open a socke.io
Sent to client socket.id to client as
So Far, looking in deep on the code and doc, I found that socket.io support namespaces, so I used this in order to manage client connection id.
at server.js
var app = express();
var server = require('http').createServer(app),
io = require('socket.io').listen(server,{ log: false });
// Rest New Process
function generateNameSpaceWs (responce, request) {
io.of("/" + id).on('connection', handler);
response.send(id);
}
app.post("/newWS", function (res, req) {
return generateNameSpaceWs(res, req);
}
at Client.js
function makeWS(){
var ws, c = new XMLHttpRequest();
c.open("GET", url, false);
c.send();
if (c.status == 200){
id = JSON.parse(c.responseText);
ws = new io.connect("server/" + id)
}
So far you are doing right, if I understand your question correctly, you are trying to authenticate connection via POST, so that user can only connect to server via socket if server responds to ID. This is a roundabout way. Use the socket instead of POST.
Socket server has to be running already, and accepts connection via io.sockets.on('connection'), at server you can choose whether to accept it or reject it ,do socket.disconnect('unauthorized') to close connection from server.
I would you suggest you do this :
Set Socket.io (at Node.js) at SERVER:PORT
Client connect to SERVER using io.connect(SERVER:PORT)
Send what you are sending in POST over socket.
Authenticate/Process on io.sockets.on('connection', function(socket) at server.
Close socket if unathorized.
Send back ID data to client.
This doesn't seem possible -- while the official documentation for socket.io is lacking, the documentation for the net module indicates that the only way to create a socket is to initiate it server side.
However, you can still achieve the desired effect by creating an id for the socket on the server to associate with the socket. That is,
Set Socket.io (at Node.js) at SERVER:PORT
Recieved POST (REST) - Server side
Create id (Note:This could be done before step 2)
At response of Post send the id!
Client connect to SERVER
using io.connect(SERVER:PORT)
The client sends the id to the server using something like
socket.emit("set_id",id)
The server recieves the id and associates it with the socket using something like
socket.on("set_id",function(id){
socket.set("id",id)
}
Now you can reference the socket using the id that you created!
Good luck!