Question

I’m working on a blue green pattern for a system with continuous delivery. I would like to force the users to switch server after 30 min. I’m developing my application in JSF 2. Is there an easy way to make the sessions end after a certain time no matter if the user is active or not?

Answer 1

Implement a filter which does basically the following job:

HttpSession session = request.getSession();

if (session.isNew()) {
    session.setAttribute("start", System.currentTimeMillis());
}
else {
    long start = (Long) session.getAttribute("start");

    if (System.currentTimeMillis() - start > (30 * 60 * 1000)) {
        session.invalidate();
        response.sendRedirect("expired.xhtml");
        return;
    }
}

chain.doFilter(request, response);

Map this on the servlet name or URL pattern of interest.

This is only sensitive to changes in system clock, make sure that your server runs UTC all the time. Otherwise better grab System#nanoTime() instead.