All Questions
13,297
questions
695
votes
12
answers
336k
views
Differences between socket.io and websockets
What are the differences between socket.io and websockets in
node.js?
Are they both server push technologies?
The only differences I felt was,
socket.io allowed me to send/emit messages by ...
- 8,208
453
votes
3
answers
248k
views
Which websocket library to use with Node.js? [closed]
Currently there is a plethora of websocket libraries for node.js, the most popular seem to be:
https://github.com/Worlize/WebSocket-Node
https://github.com/einaros/ws
https://github.com/LearnBoost/...
- 47.8k
275
votes
12
answers
143k
views
Send response to all clients except sender
To send something to all clients, you use:
io.sockets.emit('response', data);
To receive from clients, you use:
socket.on('cursor', function(data) {
...
});
How can I combine the two so that ...
- 24.8k
245
votes
13
answers
355k
views
Send message to specific client with socket.io and node.js
I'm working with socket.io and node.js and until now it seems pretty good, but I don't know how to send a message from the server to an specific client, something like this:
client.send(message, ...
- 2,901
225
votes
17
answers
280k
views
node.js TypeError: path must be absolute or specify root to res.sendFile [failed to parse JSON]
[add]
So my next problem is that when i try adding a new dependence (npm install --save socket.io). The JSON file is also valid. I get this error:
Failed to parse json
npm ERR! Unexpected string
npm ...
210
votes
3
answers
135k
views
Good beginners tutorial to socket.io? [closed]
I am very new to the world of webdevelopment and jumped into the bandwagon because I find the concept of HTML5 very interesting. I am fairly confident on working with canvas and would now like to move ...
- 11.5k
205
votes
35
answers
340k
views
How do I get a list of connected sockets/clients with Socket.IO?
I'm trying to get a list of all the sockets/clients that are currently connected.
io.sockets does not return an array, unfortunately.
I know I could keep my own list using an array, but I don't think ...
- 30.9k
193
votes
8
answers
72k
views
socket.io rooms or namespacing?
I am investigating nodejs/socket.io for real time chat, and I need some advice for implementing rooms.
Which is better, using namespace or using the room feature to completely isolate grops of ...
- 3,145
190
votes
13
answers
253k
views
node.js, socket.io with SSL
I'm trying to get socket.io running with my SSL certificate however, it will not connect.
I based my code off the chat example:
var https = require('https');
var fs = require('fs');
/**
* Bootstrap ...
- 2,070
175
votes
7
answers
240k
views
socket.emit() vs. socket.send()
What's the difference between these two?
I noticed that if I changed from socket.emit to socket.send in a working program, the server failed to receive the message, although I don't understand why.
...
- 32.4k
174
votes
4
answers
188k
views
Authenticating socket io connections using JWT
How can I authenticate a socket.io connection? My application uses a login endpoint from another server (python) to get a token, how can I get use that token whenever a user opens a socket connection ...
- 11.9k
164
votes
31
answers
302k
views
Socket.io + Node.js Cross-Origin Request Blocked
I'm using node and socket.io to write a chat application. It works fine on Chrome but mozilla gives an error to enable the Cross-Origin Requests.
Cross-Origin Request Blocked: The Same Origin ...
- 2,244
151
votes
22
answers
189k
views
Get the client's IP address in socket.io
When using socket.IO in a Node.js server, is there an easy way to get the IP address of an incoming connection? I know you can get it from a standard HTTP connection, but socket.io is a bit of a ...
- 34.2k
136
votes
14
answers
214k
views
WebSockets and Apache proxy: how to configure mod_proxy_wstunnel?
I have :
Apache 2.4 on port 80 of my server, with mod_proxy and mod_proxy_wstunnel enabled
Node.js + socket.io on port 3001 of the same server
Accessing example.com (with port 80) redirects to 2. ...
- 44.1k
135
votes
7
answers
143k
views
Node.js client for a socket.io server
I have a socket.io server running and a matching webpage with a socket.io.js client. All works fine.
But, I am wondering if it is possible, on another machine, to run a separate node.js application ...
- 3,570
134
votes
7
answers
86k
views
Socket.IO Authentication
I am trying to use Socket.IO in Node.js, and am trying to allow the server to give an identity to each of the Socket.IO clients. As the socket code is outside the scope of the http server code, it ...
- 2,102
125
votes
5
answers
191k
views
What is an example of the simplest possible Socket.io example?
So, I have been trying to understand Socket.io lately, but I am not a supergreat programmer, and almost every example I can find on the web (believe me I have looked for hours and hours), has extra ...
- 2,339
122
votes
8
answers
160k
views
How to send a message to a particular client with socket.io
I'm starting with socket.io + node.js, I know how to send a message locally and to broadcast socket.broadcast.emit() function:- all the connected clients receive the same message.
Now, I would like ...
- 3,128
122
votes
5
answers
82k
views
Socket.io rooms difference between broadcast.to and sockets.in
Socket.io's readme contains the following example:
var io = require('socket.io').listen(80);
io.sockets.on('connection', function (socket) {
socket.join('justin bieber fans');
...
- 1,753
118
votes
4
answers
100k
views
What's the difference between io.sockets.emit and broadcast?
What's the difference between io.sockets.emit and socket.broadcast.emit? Is it only that broadcast emits to everyone BUT the socket that sends it?
It seems like they can be used interchangeably:
io....
- 3,483
110
votes
2
answers
46k
views
How to remove debugging from an Express app?
I would like to remove the debugging mode. I am using express, redis, socket.io and connect-redis, but I do not know where the debugging mode comes from.
Someone has an idea?
- 1,988
101
votes
11
answers
103k
views
socket.io and session?
I'm using express framework. I want to reach session data from socket.io. I tried express dynamicHelpers with client.listener.server.dynamicViewHelpers data, but i can't get session data. Is there a ...
- 1,153
100
votes
7
answers
57k
views
How to share sessions with Socket.IO 1.x and Express 4.x?
How can I share a session with Socket.io 1.0 and Express 4.x? I use a Redis Store, but I believe it should not matter. I know I have to use a middleware to look at cookies and fetch session, but don't ...
- 10.2k
99
votes
7
answers
96k
views
Send additional data on socket connection
How to best send additional data upon socket connection?
Client:
socket.on('connect',function(){
//I'd like set some values and pass them up to the node server.
});
Node.js Server:
io.on('...
- 2,729
97
votes
3
answers
88k
views
How to integrate nodeJS + Socket.IO and PHP?
I have recently been looking around, to find a good way to communicate between nodeJS and PHP. Here is the idea : nodeJS is still quite new, and it can be kind of tricky to develop a full application ...
- 6,117
96
votes
22
answers
460k
views
WebSocket connection failed: Error during WebSocket handshake: Unexpected response code: 400
I am trying to integrate Socket.io with Angular and I'm having difficulties making a connection from the client-side to the server. I've looked through other related questions but my issue is ...
- 2,141
95
votes
8
answers
68k
views
Using socket.io in Express 4 and express-generator's /bin/www
So here is the deal: I'm trying to use socket.io in an express project. After Express Js 4 was lauched, i've updated my express-generator and now the app initial functions goes into ./bin/www file, ...
- 1,755
94
votes
6
answers
182k
views
Get connection status on Socket.io client
I'm using Socket.io, and I'd like to know the status of connection to the server from the client-side.
Something like this:
socket.status // return true if connected, false otherwise
I need this ...
- 5,895
92
votes
8
answers
43k
views
Websocket transport reliability (Socket.io data loss during reconnection)
Used
NodeJS, Socket.io
Problem
Imagine there are 2 users U1 & U2, connected to an app via Socket.io. The algorithm is the following:
U1 completely loses Internet connection (ex. switches ...
- 3,586
84
votes
6
answers
91k
views
Update all clients using Socket.io?
Is it possible to force all clients to update using socket.io? I've tried the following, but it doesn't seem to update other clients when a new client connects:
Serverside JavaScript:
I'm attempting ...
- 15.8k
83
votes
2
answers
41k
views
RabbitMQ vs Socket.io? [closed]
I'm doing real time live web app development.
Browser users should be able to communicate with eachother through a node.js server. One of the user writes a message and all other users will get it.
I ...
- 78.8k
79
votes
4
answers
47k
views
io.emit vs socket.emit
I'm new to socket.io and have run in to something that seems pretty weird. I don't actually know the difference between socket.emit and io.emit but I can't find an explanation anywhere.
io.on('...
- 1,727
78
votes
4
answers
53k
views
Separating file server and socket.io logic in node.js
I'm fairly new to node.js and I've found its quite complicated separating a project into multiple files as the project grows in size. I had one large file before which served as both a file server and ...
- 16.3k
77
votes
1
answer
137k
views
Creating Rooms in Socket.io
I would like to ask for your help. I'm having a hard time in my client side of socket.io, I would like to call this code in my client side to create a room in socket.io:
var rooms = [];
socket.on('...
- 1,441
76
votes
8
answers
40k
views
Where is the socket.io client library?
As far as I have seen, there is no explanation as to where we are to locate the client side script for socket.io if node.js is not used as the web server. I've found a whole directory of client side ...
- 821
75
votes
9
answers
149k
views
nodejs: listen EACCES: permission denied 0.0.0.0:80
I am trying to create https server to test socket io by node js. According this page
openssl genrsa -out privatekey.pem 2048
openssl req -new -key privatekey.pem -out certrequest.csr
openssl x509 -...
- 5,643
75
votes
3
answers
75k
views
Node.js EMFILE error with increasing traffic
I have very recently received a lot of traffic to my site that runs Node.js. With the increasing traffic it has started to crash a lot, which has not happened before. I get the following error in my ...
- 753
75
votes
2
answers
23k
views
how does socket.io work? [closed]
I am using socket.io and it was quick to setup (thanks to examples on their usage page) but i'd like to find out more about what exactly is going on under covers and what's the technology that makes ...
- 24.4k
72
votes
4
answers
59k
views
Scaling Socket.IO to multiple Node.js processes using cluster
Tearing my hair out with this one... has anyone managed to scale Socket.IO to multiple "worker" processes spawned by Node.js's cluster module?
Lets say I have the following on four worker processes (...
- 11.4k
72
votes
6
answers
55k
views
Unit testing Node.js and WebSockets (Socket.io)
Could anyone provide a rock-solid, dead-simple unit test for Node.js using WebSockets (Socket.io)?
I'm using socket.io for Node.js, and have looked at socket.io-client for establishing the client ...
- 1,711
69
votes
3
answers
54k
views
How to connect two node.js servers with websockets?
Here's my problem:
I have server A, running node.js and using socket.io for communicating with clients (web browsers). This all is running fine and dandy.
However, now that I have server B, which ...
- 2,698
68
votes
4
answers
31k
views
What's the difference between engine.io and socket.io?
Regarding node.js, I'm using socket.io for real-time socket connection from the client application to the server application.
I just heard about engine.io. Is engine.io a replacement for socket.io?
I ...
- 2,958
68
votes
1
answer
29k
views
Node.js, Socket.io, Redis pub/sub high volume, low latency difficulties
When conjoining socket.io/node.js and redis pub/sub in an attempt to create a real-time web broadcast system driven by server events that can handle multiple transports, there seems to be three ...
- 689
67
votes
9
answers
125k
views
socket.io-client how to set request header when making connection
I'm trying to set a http header when socket.io client makes the connection request. Is there a way to do this?
Here is what i'm doing:
// server side
var io = socketio(server);
io.use(function (...
- 1,087
63
votes
1
answer
73k
views
List of Socket.io Events
Does anyone know what events are built-in in Socket.io?
For example: connection, disconnect, join etc.
- 1,139
63
votes
4
answers
39k
views
How to protect against distributed denial-of-service attacks in Node.js with Socket.io?
I have been learning node.js and socket.io lately. My question is how can I protect server against client side attacks?
This is my server code
io.sockets.on('connection', function (socket) {
//...
- 733
62
votes
14
answers
97k
views
Socket.IO Connected User Count
I finally got Socket.IO to work properly, but I have encountered a strange problem.
I am not sure if this is the best way, but I am using:
io.sockets.clients().length
This returns the number of ...
- 23.8k
62
votes
2
answers
4k
views
Socket.IO issue with control chars
I am implementing an application that uses websockets and a console accessed via Telnet. There is a communication between the connection established via websockets and the console. I am experiencing a ...
- 3,250
61
votes
7
answers
75k
views
Send custom data along with handshakeData in socket.io?
So I have an application running node js with socket.io as a backend and normal javascript as frontend. My application has a login system which currently simply has the client send its login data as ...
- 9,835
57
votes
6
answers
106k
views
How to resolve a Socket.io 404 (Not Found) error?
I am using Socket.io with Express. In my project I have a login page and a home page. When I do successful login, I navigate to localhost:3000/home where I get this error:
GET http://localhost:3000/...
- 8,460