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Check for Client Reconnection Before Disconnect Triggers


So I'm trying to have a real-time display of my online players, and it's working great thus far except for one issue. When my app listens for the disconnect, it appears that a page refresh triggers this function and said player is logged out.

app.io.route("disconnect", function(req,res) {
    db.query("UPDATE player_data SET online=0 WHERE id="+mysql.escape(req.session.user));
    req.io.broadcast("event", {msg:req.session.username+" has logged out!"});
    app.io.broadcast("reloadXY");
    req.session.destroy();
});

Why is a page refresh triggering this function? (I know it's this function because the only other way a player is logged out is via the logout link) How can I have it ignore page refreshes and only catch disconnections like closing the browser?

Edit: how can I "ping" for the reconnect event so that I can check if the page was reloaded versus closed? A reload will have an instant re-connection, so I just need to check for said reconnection. I just don't know how!


Solution

  • Thanks to Zirak (and Tim Cooper, although at the time I had no idea what he meant), I was able to solve this issue. He suggested I store a disconnection timeout inside my session, and when there is a re-connection (instant because of page-reloads), simply clear the timeout before it auto-logs out the player.

    app.io.route("stopDisconnection", function(req) {
        if (req.session) {
            clearTimeout(req.session.disconnection);
            console.log("Timeout cleared");
        }
    });
    
    app.io.route("disconnect", function(req) {
        req.session.disconnection = setTimeout(function() {
            console.log("User timed out!");
            db.query("UPDATE player_data SET online=0 WHERE id="+mysql.escape(req.session.user));
            app.io.broadcast("event", {msg:req.session.username+" has logged out!"});
            app.io.broadcast("reloadXY");
            req.session.destroy();
        },5000);
    });
    

    And simply call io.emit("stopDisconnection") on index.html

    And with that, you can successfully trigger a disconnect function without having to worry about a page refresh also trigger the event.