Either it may be simple servlet, spring-mvc or spring-security auto logout is not possible without perfect client side logic.
Considering application will have both type of request
- AJAX and
- form submission/page reload
Auto logout needs very calculated logic. Presenting my autologout functionality implementation with following
Advantages.
Usage
1. Include auto logout script in required JSP pages as given below.
....
</body>
<jsp:include page="../template/autologout-script.jsp"></jsp:include>
</html>
2. Create a JSP page, autologout-script.jsp and add below code.
Note: No editing/configuring is required
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<script>
$(document).ready(function()
{
var timeOutTimeInSeconds = ${ timeOutTimeInSeconds };
var showTimerTimeInSeconds= ${ showTimerTimeInSeconds };
var sessionCheckIntervalId = setInterval(redirectToLoginPage, timeOutTimeInSeconds * 1000);
var timerDisplayIntervalId = setInterval(showTimer, (timeOutTimeInSeconds - showTimerTimeInSeconds) * 1000);
var badgeTimerId;
window.localStorage.setItem("AjaxRequestFired", new Date());
function redirectToLoginPage(){
//location.href = '<c:url value="/" />'+'${loginPageUrl}';
window.location.reload();
}
$(document).ajaxComplete(function () {
resetTimer();
});
$(window).bind('storage', function (e) {
if(e.originalEvent.key == "AjaxRequestFired"){
console.log("Request sent from another tab, hence resetting timer")
resetTimer();
}
});
function resetTimer()
{
showTimerTimeInSeconds= ${ showTimerTimeInSeconds };
console.log("timeOutTimeInSeconds : "+timeOutTimeInSeconds)
window.localStorage.setItem("AjaxRequestFired", new Date());
window.clearInterval(sessionCheckIntervalId);
sessionCheckIntervalId = setInterval(redirectToLoginPage, timeOutTimeInSeconds * 1000);
window.clearInterval(timerDisplayIntervalId);
timerDisplayIntervalId = setInterval(showTimer, (timeOutTimeInSeconds - showTimerTimeInSeconds) * 1000);
hideTimer();
}
function showTimer()
{
$('#sessionTimeRemaining').show();
$('#sessionTimeRemainingBadge').html(showTimerTimeInSeconds--);
window.clearInterval(timerDisplayIntervalId);
badgeTimerId = setInterval(function(){
$('#sessionTimeRemainingBadge').html(showTimerTimeInSeconds--);
}, 1000);
}
function hideTimer()
{
window.clearInterval(badgeTimerId);
$('#sessionTimeRemaining').hide();
}
});
</script>
3. Configure session attributes to configuring timeout setting
Note: Configure this after session creation. You can implement HttpSessionListener sessionCreated method and set the following configuration as per your requirement.
session.setMaxInactiveInterval(300);
session.setAttribute("timeOutTimeInSeconds", 300);
session.setAttribute("showTimerTimeInSeconds", 30);
4. Add below html for displaying timer.
Note: it can be moved to autologout-script template page if you are good at CSS. Hence you can avoid to add this in each and every page.
Include bootstrap or add your custom css.
<span class="badge badge-primary" title="click to keep session alive" id="sessionTimeRemaining"
onclick="ajaxSessionRefresh()" style="display:none;">
<i class="badge badge-danger" id="sessionTimeRemainingBadge" style="float:left">30</i>
<small>Refresh</small>
<i class="glyphicon glyphicon-refresh"></i>
</span>
That is all about a simple auto logout implementation.
You can download working example from my github repository
Autologout using simple servlet example
Autologout using spring-security java configuration example
Autologout using spring-security xml configuration example
Logic Explained
Case 1: On Page loadCase 2: Keep track AJAX callsCase 3: Tracking multi tab/window activityLimitations/Improvements required
1. If maximum allowed session is one, if session is taken from another system, AJAX request will fail. It needs to be handled to redirect to login page.
2. Use ajaxStart() instead of ajaxComplete() to have exact sync of idleTime values between server and browser.
Requirements
1. Jquery
Alternatives to current implementation compared
Setting Refresh header(Not works for AJAX requests)response.setHeader("Refresh", "60; URL=login.jsp");
- Setting meta refresh tag in HTML (Not works for AJAX requests)
<meta http-equiv="refresh" content="60; url=login.jsp">
- Configuring Activity checker
Keeps session alive by repeated AJAX request. Tracks idle time and makes logout request after timeout.
No doubt it is a good one with simple logic. But i want to just ink my observations.
- Performance impact if 2 requests are made per minute to keep session alive and 50k active users. 100k requests per minute.
- Intertab communication If two tabs are open, one tab is receiving activity but other tab is not receiving activity, that tab fires logout request and invalidate session even though activity is present in other tab. (But can be handled)
- Force logout approach It is a client is dominated over server to invalidate session.