node.js: sending a number with connection initiate - node.js

sorry, but i have a problem. I have progged a community. I want ro realize a 1:1-Chat in this community.
If a user logs in at the community, he's initiate a connection in the login.php-File:
var socket = io.connect("http://localhost:8080");
Now the question: can i send the userid with this line?
Because i want to store a pair of numbers in my sql-DB on the chatserver: the connection id and the id of the communitymember. That's because i have to inform a communitymember in chat if his chatpartner is logout and unreachable.
Very Thanks!!! And sorry for my bad english.

On the client, just pass the user id as a query string.
var socket = io.connect('http://localhost:8080?user=123');
On the server, you will probably want to handle the data in a connection handler. To do this, you have to add an authorization handler, and save the data into the handshakeData object. You can then access it on socket.handshake.
io.set('authorization', function (handshakeData, callback)
{
handshakeData.userId = handshakeData.query.user;
callback(null, true);
});
io.sockets.on('connection', function(socket)
{
console.log(socket.id, ' => ', socket.handshake.userId);
}

Related

How to safely get the current user id in socket.io/Node.JS?

I am developing a simple API for a chat application on Node.js Express, and by assignment, it is required to make it possible to communicate between two users using socket.іо. I am faced with the problem that I cannot "safely" transfer information about the current user to the socket in any way. Information about the user with whom the correspondence is conducted can be specified in the socket parameters when connecting, which I do, but what about the current user (me)?
For example, I can do this:
const {receiverId, myId} = socket.handshake.query;
That is, specify both ids when connecting. But this is very unsafe because anyone who will join the socket can specify any id and write anything on behalf of someone else (for example, through Postman WebSockets).
Another option I was considering is making a post request in which a connection to the socket will be created using request.user.id and the request parameter. Then the post request will look like this:
router.post('/chat/:receiver', function (req,res){
const {receiver} = req.params
const socket = io.connect('/')
socket.emit('initMyUserId', {
myId: req.user,
});
})
But this option also did not work, because the file where this function is located and the file where the io variable is initialized are different, and I am not sure that it is generally advisable to transfer and use it in this way. Moreover, this approach will not allow me to check the operation of sockets via Postman, because the connection will occur in a post request, and not manually.
Are there working options to safely transfer the current user id with the ability to test it normally in postman? Or at least just safely pass the current user id if it doesn't work with Postman.
Here is the full code snippet for the socket events handlers:
module.exports = function(io) {
io.on('connection', (socket)=>{
const {id} = socket;
console.log(Socket connected: ${id});
const {idUser} = socket.handshake.query;
console.log(Socket idUser: ${idUser});
socket.on('message-to-user', (msg) => {
msg.type = user: ${idUser};
socket.to(idUser).emit('message-to-user', msg);
socket.emit('message-to-user', msg);
});
socket.on('disconnect', () => {
console.log(Socket disconnected: ${id});
});
});
}

How to get current socket object or id with in a sails controller?

I would like to access the currently connected socket id with in a sails.js (v0.12 ) controller function.
sails.sockets.getId(req.socket); is showing undefined since this is not a socket request
My objective is to set the online status of my user in the database when he logged in successfully
login: function (req, res) {
Util.login(req, function(){
var socketId = sails.sockets.getId(req.socket);
console.log('socketId ===', socketId); // return undefined
});
},
Basically i would like to access the current user's socket object in a controller or access current user's session object with in a socket on method
Also i'm not sure that how can i rewrite my old sockets.onConnect
handler
onConnect: function(session, socket) {
// Proceed only if the user is logged in
if (session.me) {
//console.log('test',session);
User.findOne({id: session.me}).exec(function(err, user) {
var socketId = sails.sockets.getId(socket);
user.status = 'online';
user.ip = socket.handshake.address;
user.save(function(err) {
// Publish this user creation event to every socket watching the User model via User.watch()
User.publishCreate(user, socket);
});
// Create the session.users hash if it doesn't exist already
session.users = session.users || {};
// Save this user in the session, indexed by their socket ID.
// This way we can look the user up by socket ID later.
session.users[socketId] = user;
// Persist the session
//session.save();
// Get updates about users being created
User.watch(socket);
// Send a message to the client with information about the new user
sails.sockets.broadcast(socketId, 'user', {
verb :'list',
data:session.users
});
});
}
},
You need to pass the req object to the method.
if (req.isSocket) {
let socketId = sails.sockets.getId(req);
sails.log('socket id: ' + socketId);
}
Since the request is not a socket request, you might need to do something like
Send back some identifier to the client once logged in.
Use the identifier to join a room. (One user per room. )
Broadcast messages to the room with the identifier whenever you need to send message to client.
https://gist.github.com/crtr0/2896891
Update:
From sails migration guide
The onConnect lifecycle callback has been deprecated. Instead, if you need to do something when a new socket is connected, send a request from the newly-connected client to do so. The purpose of onConnect was always for optimizing performance (eliminating the need to do this initial extra round-trip with the server), yet its use can lead to confusion and race conditions. If you desperately need to eliminate the server roundtrip, you can bind a handler directly on sails.io.on('connect', function (newlyConnectedSocket){}) in your bootstrap function (config/bootstrap.js). However, note that this is discouraged. Unless you're facing true production performance issues, you should use the strategy mentioned above for your "on connection" logic (i.e. send an initial request from the client after the socket connects). Socket requests are lightweight, so this doesn't add any tangible overhead to your application, and it will help make your code more predictable.
// in some controller
if (req.isSocket) {
let handshake = req.socket.manager.handshaken[sails.sockets.getId(req)];
if (handshake) {
session = handshake.session;
}
}

Socket - send message to user by ID

I'm using Node.js with ws(a socket library) and I'm having a little trouble with finding the socket of a specific user.
when the user connects to my socket server, I'm supposed to keep his socket objct in a big massive object by his userID or socketID like this:
var bigMassiveObject = {};
ws.on('connection', function(socket){
var userID //somehow get the userID
bigMassiveObject[userID] = socket;
// to find the socket
socket = bigMassiveObject[userID];
socket.send("hi");
})
so that later I can send him message by that ID, but isn't it better to just keep his socketID? this way we are not storing all the socket, but only the ID and then somehow(which I don;t know) send him message by that ID
this is what i'm looking for:
var smallObject = {};
ws.on('connection', function(socket){
var userID //somehow get the userID
smallObject[userID] = socketID;
// to find the socket
var socket = generateSocketObjectBySocketID(socketID);
socket.send("tada!");
})
so the question is, is there anyway to generate the socket, by the socketID(or useID)? so that we wouldn't be storing all these big socket objects in memory and there wouldn't be any memory leakage too :)
Simply,
This is what you need :
io.to(socket.id).emit("event", data);
whenever a user joined to the server,socket details will be generated including ID.This is the ID really helps to send a message to particular people.
first we need to store all the socket.ids in array,
var people={};
people[name] = socket.id;
here name is the reciever name. Example:
people["trojan"]=2387423cjhgfwerwer23;
So, now we can get that socket.id with the reciever name whenever we are sending message:
for this we need to know the recievername.You need to emit reciever name to the server.
final thing is:
socket.on('chat message', function(data){
io.to(people[data.reciever]).emit('chat message', data.msg);
});
Hope this works well for you.!!Good Luck

SocketIO - processing data before broadcasting

I am currently having a problem with a small Node.JS application. It is extremely similar to, for example, the Socket.IO sample chat application: whenever an user sends data to the server, I need to process the data and then broadcast it to all users. However, the way data is processed depends on the user that receives it. I tried altering the Socket#emit method (in order to process the data before sending it) for each socket, but the broadcasting doesn't use it. Is there any way I can get this solved?
Thanks in advance.
EDIT
Here is what I'd tried ():
var io = require('socket.io');
io.use(function(socket, next) {
var old_emit = socket.emit;
socket.emit = function() {
// do something with the data (arguments[1] in this case)
// the processing of the data depends on a value that is
// unique to each connection, and can't be sent over to the client
old_emit.apply(socket, arguments);
}
});
I tried the code above because I thought, initially, that broadcasting would call emit somewhere else for each connection.
I am not sure what you want to do,
There is no any "io( )" like function.You are doing it wrong.
BTW, to process data.
From sample chat application,
// when the client emits 'new message', this listens and executes
socket.on('new message', function (data) {
//call a function which you want to process data
var newData = messageProcessingFunc(data);
//and then broadcast it.
// we tell the client to execute 'new message'
socket.broadcast.emit('new message', {
username: socket.username,
message: newData
});
});

socket.io private message

I've beeen scouring the Net with no luck. I'm trying to figure out how to send a private message from one user to another. There are lots of snippets, but I'm not sure about the client/server interaction. If I have the ID of the socket I want to send to, how do I send it to the server, and how do I ensure the server only sends the message to that one receiver socket?
Is there a tutorial or walkthrough that anyone knows of?
No tutorial needed. The Socket.IO FAQ is pretty straightforward on this one:
socket.emit('news', { hello: 'world' });
EDIT: Folks are linking to this question when asking about how to get that socket object later. There is no need to. When a new client connects, save a reference to that socket on whatever object you're keeping your user information on. My comment from below:
In the top of your script somewhere, setup an object to hold your users' information.
var connectedUsers = {};
In your .on('connection') function, add that socket to your new object. connectedUsers[USER_NAME_HERE] = socket; Then you can easily retrieve it later. connectedUsers[USER_NAME_HERE].emit('something', 'something');
Here's a code snippet that should help:
Client-side (sending message)
socket.emit("private", { msg: chatMsg.val(), to: selected.text() });
where to refers to the id to send a private message to and msg is the content.
Client-side (receiving message)
socket.on("private", function(data) {
chatLog.append('<li class="private"><em><strong>'+ data.from +' -> '+ data.to +'</strong>: '+ data.msg +'</em></li>');
});
where chatLog is a div displaying the chat messages.
Server-side
client.on("private", function(data) {
io.sockets.sockets[data.to].emit("private", { from: client.id, to: data.to, msg: data.msg });
client.emit("private", { from: client.id, to: data.to, msg: data.msg });
});
Although we have nice answers here. However, I couldn't grasp the whole client server unique user identification pretty fast, so I'm posting this simple steps in order to help whoever is struggling as i did.....
At the client side, Get the user's ID, in my case I'm getting the username...
Client side user registration
//Connect socket.io
var systemUrl = 'http://localhost:4000';
var socket = io.connect(systemUrl);
//Collect User identity from the client side
var username = prompt('Enter your Username');
socket.emit('register',username);
The Listen to register on the server side to register user's socket to connected socket
Serve side code User registration
/*Craete an empty object to collect connected users*/
var connectedUsers = {};
io.on('connection',function(socket){
/*Register connected user*/
socket.on('register',function(username){
socket.username = username;
connectedUsers[username] = socket;
});
});
Send Message from the client side
$(document).on('click','.username',function(){
var username = $(this).text(),
message = prompt("type your message");
socket.emit('private_chat',{
to : username,
message : message
});
});
Receive message on server and emit it to private user
/*Private chat*/
socket.on('private_chat',function(data){
const to = data.to,
message = data.message;
if(connectedUsers.hasOwnProperty(to)){
connectedUsers[to].emit('private_chat',{
//The sender's username
username : socket.username,
//Message sent to receiver
message : message
});
}
});
Receive message on client and display it
/*Received private messages*/
socket.on('private_chat',function(data){
var username = data.username;
var message = data.message;
alert(username+': '+message);
});
This is not the best, however you can start from here....
The easiest way I can think of is to have an hash of all the users on using their id or name as the key and have their socket as part of the value then when you want to send a message to just them you pull that socket and emit on it... something like this:
users[toUser].emit('msg',"Hello, "+toUser+"!");
if you have a web site that has register users with uid then you can create a room for each user and name the room by uid of the user.
first connect client to the server using :
var socket = io('server_url');
on the server side create an event for detecting client connection:
io.on('connection', function (socket) {}
then you can emit to client inside it using socket.emit(); and ask uid of current user.
on the client side create an event for this request and then send uid of the user to server.
now on server side join the connected socket to room using :
socket.join(uid);
console.log('user ' + socket.user + ' connected \n');
now you can send private message to a user using following line:
io.to(uid).emit();
if you use the code above, it doesn't matter how many tab user has already open from your web site . each tab will connect to the same room.
in socket.io 1.0 use
io.sockets.connected[<socketid>]
you can store just socket id. like so:
var users = {};
users[USER_NAME] = socket.id;
then:
io.sockets.connected[users[USER_NAME]]
.emit('private', {
msg:'private message for user with name '+ USER_NAME
});
You can create an unique room for messaging between USER_A and USER_B and both users must join to this room. You may use an UUID as a ROOM_ID (the 'socketId' in the following example).
io.on('connection', socket => {
socket.on('message', message => {
socket.to(message.socketId).emit('message', message);
});
socket.on('join', socketId => {
socket.join(socketId);
});
});
See Joining Rooms and Emit Cheatsheet
The way I got it to work is by introducing one more event "registered user". This basically triggers on the client side as soon as there is a registered user and then emits this even and passes "currentUser._id"
Client Side:
var socket = io();
<% if (currentUser) { %>
socket.emit('registered user', "<%= currentUser._id %>");
<% } %>
Server Side: Once the "registered user" even triggers, it joins the current user socket to the new room with the name which is that user id. So basically each registered user will be in a room which is his/her uid.
socket.on('registered user', function (uid) {
socket.join(uid)
});
Server Side: One there is a message sent, I pass the id of the user the message is sent to in the msg object and then emit to that specific room.
// Private chat
socket.on('chat message', function (msg) {
const uidTo = msg.uidTo
socket.in(uidTo).emit('chat message', msg )
}); `
});

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