I want to get the previous session data if the user removes all his cookies manually or in other methods. Because i am storing some data in session and in my global too, and I need to remove that data from my global for every session destroyed.
If a user removes all his cookies, then he is a user without cookies, right? So how would you differentiate between this user and any other user? This is a very difficult problem and I doubt there is a reliable solution for it.
For example you might want to identify a user by IP, but IP might change ( dynamic IP ). You might want to identify user by creating WebSocket ( of FlashSocket ) connection and keep it open, but this will work only when user views your page ( and might be closed manually as well ).
So forget about previous sessions. If you need to clean session data, then create a CRON job or background thread ( or background asynchronous job in case of Node.JS ), which will do that periodically. Or you can just use passive cleaning, i.e. implement mechanism for sessions, that will clean itself when getting near the ( predefined ) memory limit ( this should fire when creating a new session ).
I just set the session to expire automatically in redis, so it will clean itself up over time. Unfortunately, I forget how I did this exactly, I think it's a property on the db.
When someone logs out, I destroy the session:
req.session.destroy(function(){
//session has been destroyed
});