Question

I’ve seen this question asked a few ways and the solutions are generally for other languages and don’t apply to ASP.NET MVC 2.

I am using Jquery & Jquery forms to auto-save user data at a set interval. I still want the application to be able to time out, but the auto-saves via jquery forms keep refreshing the server.

My initial idea to fix this was pretty simple. I’ve already got an ActionFilter I use to see if the session expires. Well, the session won’t ever expire; however, I just keep track of how many auto saves occurr based on a value in session and when it reaches a limit (specified in the web.config), it does a:

 filterContext.Result = new RedirectResult("~/Account.aspx/LogOn");

Well, this doesn’t work because the auto save is doing an ajaxFormSubmit to call the action in the first place. I’ve tried changing the action to redirect to the login page, but the same thing happens….it just doesn’t do a redirect. The only thing the action can return is a Json result. In my latest version (code below) I’m setting the json return value to false and calling a redirectToLogin() function to send the page over to the login page. It doesn’t work and i’m not sure why.

Any thoughts on this would be most helpful.

Excerpt of code that sets up the interval for autosaving on the view (placed just before the form is closed):

<%
    double sessionTimeoutInMinutes = double.Parse(ConfigurationManager.AppSettings["SESSION_TIMEOUT_IN_MINUTES"].ToString());
    double maxContiguousAutoSaves = double.Parse(ConfigurationManager.AppSettings["MAX_CONTIGUOUS_AUTO_SAVES"].ToString());           
    double autoSaveInterval = (sessionTimeoutInMinutes / maxContiguousAutoSaves) * 60 * 1000;               
%>

    <%= Html.Hidden("autoSaveInterval", autoSaveInterval) %>

    <script type="text/javascript">
        $(document).ready(function() {
            var autoSaveFrequency = $('[id=autoSaveInterval]').val();
            //alert(' Auto Save Interval in miliseconds: ' + autoSaveFrequency);                
            setInterval(
                "initAutoSave('AutoSaveGoals', 'message')"
                , autoSaveFrequency);
        });

    </script>       

“AutoSaveGoals” goals is the name of one of my actions. It handles the post, updates certain items in session, and calls the repository.update. It is defined below:

   [HttpPost]
    public ActionResult AutoSaveGoals(Data data)
    {
        Data sessdata = Data();
        sessdata.MpaGoals = data.Goals;
        sessdata.MpaStatus = data.MpaStatus;
        sessdata.StartPeriodDate = data.StartPeriodDate;
        sessdata.EndPeriodDate = data.EndPeriodDate;
        sessdata.AssociatePassword = data.AssociatePassword;

        try
        {
            _repository.update(sessdata);
        }
        catch (Exception e)
        {
            LogUtil.Write("AutoSaveGoals", "Auto Save Goals Failed");
            LogUtil.WriteException(e);
        }

                    if (!autoLogOffUser(RouteData.GetRequiredString("action")))
            return Json(new { success = true });
        else
            return Json(new { success = false });

    }

The initAutoSave function is javascript that uses Jquery & Jquery Forms plugin. Here it is:

function initAutoSave(targetUrl, messageDivId) {
    var options = {
        url: targetUrl,
        type: 'POST',
        beforeSubmit: showRequest,
        success: function(data, textStatus) {
            //alert('Returned from save! data: ' + data);
            if (data.success) {
                var currDateAndTime = " Page last saved on: " + getCurrentDateAndTime();
                $('[id=' + messageDivId + ']').text(currDateAndTime).show('normal', function() { })
            }
            else {
                alert('redirecting to login page');
                redirectToLogin();
                //$('[id=' + messageDivId + ']').text(' An error occurred while attempting to auto save this page.').show('normal', function() { })
                //alert('ERROR: Page was not auto-saved properly!!!!');
            }
        }
    };
    $('form').ajaxSubmit(options);
}

I try doing a javascript redirect in redirectToLogin() but it doesn’t seem to get the url or something behind the scenes is blowing up. Here is how it’s defined:

function redirectToLogin() {    
    window.location = "Account.aspx/LogOn";
}

Answer 1

Now this is just absurd…So, I was looking over my applications (I’ve got several going to QA soon) and noted that I’ve already solved this very question with a much better solution – it was ALL handled in an ActionFilter. I wanted this from the getgo when I asked this question, but to have already implemented it, forgot about that, AND ask again on Stack Overflow…well, I hope my memory issues helps somebody with this. Below is the full action filter code. As always, I’m open to criticism so mock it, revise it, copy it, etc, etc.

public class UserStillActiveAttribute : ActionFilterAttribute
{
    public override void OnActionExecuted(ActionExecutedContext filterContext)
    {

        int sessionTimeoutInMinutes = int.Parse(ConfigurationManager.AppSettings["SESSION_TIMEOUT"].ToString());
        int maxContiguousAutoSaves = int.Parse(ConfigurationManager.AppSettings["MAX_CONSEC_SAVES"].ToString());
        int autoSaveIntervalInMinutes = int.Parse(ConfigurationManager.AppSettings["AUTO_SAVE_INTERVAL"].ToString());

        string actionName = filterContext.ActionDescriptor.ActionName;
        string controllerName = filterContext.ActionDescriptor.ControllerDescriptor.ControllerName;

        HttpContext currentSession = HttpContext.Current;      

        LogAssociateGoalsSessionStatus(filterContext.HttpContext, actionName);

        if (actionName.ToLower().Contains("autosave"))
        {
            int autoSaveCount = GetContigousAutoSaves(filterContext.HttpContext);
            if (autoSaveCount == maxContiguousAutoSaves)
            {
                var result = new RedirectResult("~/Account.aspx/LogOff");
                if (result != null && filterContext.HttpContext.Request.IsAjaxRequest())
                {
                    //Value checked on Logon.aspx page and message displayed if not null
                    filterContext.Controller.TempData.Add(PersistenceKeys.SessionTimeOutMessage,
                        StaticData.MessageSessionExpiredWorkStillSaved);

                        string destinationUrl = UrlHelper.GenerateContentUrl(
                                                result.Url,
                                                filterContext.HttpContext);
                    filterContext.Result = new JavaScriptResult()
                    {
                        Script = "window.location='" + destinationUrl + "';"
                    };
                }
            }
            else
            {
                RefreshContiguousAutoSaves(filterContext.HttpContext, autoSaveCount + 1);
            }
        }
        else
        {
            RefreshContiguousAutoSaves(filterContext.HttpContext, 1);
        }

    }

    private int GetContigousAutoSaves(HttpContextBase context)
    {
        Object o = context.Session[PersistenceKeys.ContiguousAutoUpdateCount];
        int contiguousAutoSaves = 1;

        if (o != null && int.TryParse(o.ToString(), out contiguousAutoSaves))
        {
            return contiguousAutoSaves;
        }
        else
        {
            return 1;
        }
    }

    private void RefreshContiguousAutoSaves(HttpContextBase context,
                                            int autoSavecount)
    {
        context.Session.Remove(PersistenceKeys.ContiguousAutoUpdateCount);
        context.Session.Add(PersistenceKeys.ContiguousAutoUpdateCount,
                                    autoSavecount);
    }

    private void LogAssociateGoalsSessionStatus(HttpContextBase filterContext, string actionName)
    {
        AssociateGoals ag = (AssociateGoals)filterContext.Session[(PersistenceKeys.SelectedAssociateGoals)];
        bool assocGoalsIsNull = false;
        bool assocGoalsInformationIsNull = false;

        if (ag == null)
        {
            assocGoalsIsNull = true;
            assocGoalsInformationIsNull = true;
        }
        else if (ag != null && ag.AssociateInformation == null)
            assocGoalsInformationIsNull = true;
    }
}