Is it possible to make such a connection (socket.io)?

Question

Node.js

Before connecting via socket.io, authorization occurs. At this point, you can either accept the connection or cancel it.
I want to do a check on the user's ip and in the case of an existing connection on this ip, transfer the existing object to a new connection, and close the old one.
Example: a user on tab A enters a website, a ws connection is opened and information flows through it. Then the user in tab B visits the same site. Instead of creating a new ws connection, information from tab A begins to flow to tab B, while A closes.
Perhaps so?
I think, if possible, it should be done in this function:

io.set('authorization', function (handshakeData, callback) {
      // проверка по ip и настройка соединения
  });

I didn't try, I didn't succeed

Answer 1

What's difficult? Store the user's IP and the socket ID or key that you have there to identify socket connections.
If the client fell off - we throw it out of this array, if it is hooked - we replace the old hash key with a new one (new tab).
When connecting, some kind of authorization function must be called, which will say "ok / no". Well, you just need to insert into each handler a check of the current connection identifier for the presence in the active array - if it is not there, we call the client method, in the handler of which we close the socket connection to the server and that's it.

Answer 2

Do you absolutely need the user to be disconnected if he opens a new tab?
Basically, you are doing everything right. But I would recommend making sessions not an object, but an array where session objects will be stored. Based on this, you get something like this:
Include the underscore module at the beginning of the file (underscore.js library ) Next
, write inio.sockets.on('connection')

// массив сессий
var sessions = [],
      ip = ?; // ваша реализация

// проверяем, имеется ли уже активная сессия
var found = (_.find(sessions, function(session) {
     return session.ip === ip;
}));

// обновляем (не удаляем!) сессию, если нашли, сказав предыдущей вкладке "пока-пока"
if (found) {
      found.socket.emit('bye_bye', 'You are disconnected from server');
      found.socket.disconnect();
      found.socket = socket;
      found.ip = ip;
}
else {
      // добавляем сессию
      sessions.push({
             socket: socket,
             ip: ip
      });
}

All this is written in connection, because. you are autzorizathionnot yet connected to the socket.
PS The code is just an unoptimized and untested prototype