[SOLVED] Automatically perform action in client side when the session expires

Automatically perform action in client side when the session expires

I want to display in a <p:growl> that the session has expired.

I found many methods to handle session expiration like:

Session timeout and ViewExpiredException handling on JSF/PrimeFaces ajax request

But I couldn't push a faces message to <p:growl>.

To the point, how can I automatically run some (JavaScript) code in client side when the HTTP session has automatically expired in server side?

Solution

You can use PrimeFaces idle monitor for this. User is redirected to logout action after timeout to invalidate the session. 2 minutes before a countdown dialog is shown to warn user. After moving the mouse again session is extended.

PrimeFaces idle monitor and dialog is placed in a template you can add to every page which is involved:

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
   xmlns:h="http://java.sun.com/jsf/html"
   xmlns:ui="http://java.sun.com/jsf/facelets"
   xmlns:p="http://primefaces.org/ui">

<ui:composition>
   <h:form prependId="false">
      <p:idleMonitor
     timeout="#{session.maxInactiveInterval * 1000 - 125000}"
     onidle="startIdleMonitor()"
     onactive="timeoutDialog.hide()" />

      <p:dialog id="timeoutSession"
     header="#{msg['session.expire']}"
     widgetVar="timeoutDialog"
     showEffect="fade" hideEffect="fade"
     modal="true"
     width="400"
     height="110"
     closable="false"
     draggable="false"
     resizable="false"
     appendToBody="true"
     onHide="stopCount()"
     onShow="doTimer()">
     <br />
     <p>
        <span class="ui-icon ui-icon-alert" style="float: left; margin: 8px 8px 0;"/>
        <p:panel>
           #{msg['logoff.soon.1']}
           <span id="dialog-countdown" style="font-weight: bold"></span>
           #{msg['logoff.soon.2']}
        </p:panel>
     </p>
     <br />
     <p style="font-weight: bold;">#{msg['move.cursor']}</p>
      </p:dialog>
      <p:remoteCommand name="keepAlive" actionListener="#{auth.keepSessionAlive}" />
   </h:form>
   <script type="text/javascript">
      var TIME = 120; // in seconds
      var countTimer = TIME;
      var processTimer;
      var timer_is_on = 0;
      var redirectPage = "#{request.contextPath}/auth/j_verinice_timeout";

      var countDownDiv = "dialog-countdown";
      var txtCountDown = null;
      if (!txtCountDown)
        txtCountDown = document.getElementById(countDownDiv);

      function startIdleMonitor() {
        countTimer = TIME;
        txtCountDown.innerHTML = countTimer;
        timeoutDialog.show();
      }
      function timedCount() {
        txtCountDown.innerHTML = countTimer;
        if (countTimer == 0) {
            stopCount();
            window.location.href = redirectPage;
            return;
        }
        countTimer = countTimer - 1;
        processTimer = setTimeout("timedCount()", 1000);
      }
      function doTimer() {
        if (!timer_is_on) {
            timer_is_on = 1;
            timedCount();
        }
      }
      function stopCount() {
        clearTimeout(processTimer);
        timer_is_on = 0;
        keepAlive();
      }
      </script>
</ui:composition>
</html>

Line 11: The timeout of the idle monitor is set by system var session.maxInactiveInterval. The value you set in your web.xml or server configuration.
Line 12/13: Javascript method startIdleMonitor() is called after timeout without any user interaction. This method opens the dialog. timeoutDialog.hide() is called when user is busy again: Dialog is closed
Line 26/27: Two more Javascript methods are called when dialog is shown or hide: doTimer() starts and stopCount() stops the countdown.
Line 40: PrimeFaces remote command to keep session alive. By calling an arbitrary method on server the session is extended. Command is called by Javascript method keepAlive() in line 78.
Line 59-68: Javascript method timedCount() is called every second to execute the countdown. After timeout redirect is done in line 63.

To activate timeout handling in multiple pages include the timeout template in your layout template:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
  xmlns:h="http://java.sun.com/jsf/html"
  xmlns:ui="http://java.sun.com/jsf/facelets"
  xml:lang="de-DE">
<h:head>
  ...
</h:head>
<body>
  <ui:include src="/template/sessionTimeOut.xhtml" />
  <ui:include src="/nav.xhtml"/>>
  <ui:insert name="content">Default content</ui:insert>
  <ui:include src="/footer.xhtml"/>>
</body>
</html>

A specific time out for your web application you can set in your web.xml:

<!--?xml version="1.0" encoding="UTF-8"?-->
<web-app>
   ...
   <session-config>
      <!-- Session idle timeout in min. -->
      <session-timeout>30</session-timeout>
    </session-config>
</web-app>

You can read more about this solution in this blog post: JSF and PrimeFaces: Session Timeout Handling