Best Practices for Implementing Two Layout Variants Based on User Authentication in Kentico 13 MVC

Florian Lauenstein asked on August 12, 2023 18:34

Hello Kentico Community,

I am currently working on a Kentico 13 MVC application that essentially has two "homepages" depending on whether a user is logged in or not. I have set up Content-Based Routing in Kentico, and the majority of the system is working as intended. However, I am facing a challenge with the initial request to the root ("/") when the user is authenticated.

Here's my code in

_ViewStart.cshml

@{
    if (Context.User.Identity?.IsAuthenticated ?? false)
    {
        Layout = "~/Views/Shared/_DashboardLayout.cshtml";
    }
    else
    {
        Layout = "~/Views/Shared/_HomeLayout.cshtml";
    }
}

Everything works perfectly, except the first request to "/" when redirected to "/{culture}". During this first request, I get an exception:

InvalidOperationException: The model item passed into the ViewDataDictionary is of type 'Kentico.PageBuilder.Web.Mvc.ComponentDefaultViewModel1[Generic.Features.Home.HomePageTemplateProperties]', but this ViewDataDictionary instance requires a model item of type 'Generic.Features.Dashboard.DashboardViewModel'.

As I understand, this is happening because of the model type expected during the initial request, but I'm at a loss as to how to work around this situation.

The core question here is: What changes do I need to make to ensure that the initial "/" calls the "/Dashboard" controller when the user is authenticated, and not the via the Kentico PageBuilder?

I would appreciate insights into the best practices for handling this specific scenario, and any guidance you can provide to help resolve this challenge.

I am using K13.0.115, MVC, .Net 6 with Content Based Routing.

Thank you for your support and looking forward to your valuable feedback!

Best Regards, Florian

k13 mvc

Recent Answers

Jono Rickard answered on September 26, 2023 04:42

Heya Florian,

Id need a bit more info to diagnose this specific error - but generally that exception means kentico has the deafult ComponentDefaultViewModel<HomePage> and expects your view to have @model ComponentDefaultViewModel<HomePage>, but your view instead has a @model DashboardViewModel

There are a few ways you couldve set this up, but for this case I would reccommend doing the is logged in/not logged in using a controller eg HomePageController for the page template and registering it with

[assembly: RegisterPageRoute(HomePage.CLASS_NAME, typeof(HomePageController))]

This links any urls that resolve to the home page in the content tree to the Index() method of your HomePageController.

From there you can check if there is a logged in user, and Redirect to the Dashboard url.

Best pratice here is to not use static urls in the BE - so that the content tree is fully functional - so in this case HomePageController.Index() could look something like this;

[assembly: RegisterPageRoute(HomePage.CLASS_NAME, typeof(HomePageController))]

public class HomePageController
{
    //Used to get the current page context
    private readonly IPageDataContextRetriever pageDataContextRetriever;

    //Used to convert a TreeNode instance into its url in the content tree
    private readonly IPageUrlRetriever pageUrlRetriever;

    //Standard way to inject the httpcontext into the controller
    private readonly IHttpContextAccessor httpContextAccessor;

    //Used to make a query to the Kentico Tree db to retrieve a TreeNode (in our case a Dashboard page)
    private readonly IPageRetriever pageRetriever;

    public HomePageController(IPageDataContextRetriever pageDataContextRetriever, IPageUrlRetriever pageUrlRetriever, IHttpContextAccessor httpContextAccessor, IPageRetriever pageRetriever){
        this.pageDataContextRetriever = pageDataContextRetriever;
        this.pageUrlRetriever = pageUrlRetriever;
        this.httpContextAccessor = httpContextAccessor;
        this.pageRetriever = pageRetriever;
    }

    [HttpGet]
    public IActionResult Index(){
        // Check the request is actually for the page type we expect
        if (pageDataContextRetriever.TryRetrieve<HomePage>(out var data) 
           && data?.Page is HomePage currentPage)
        {
            if (httpContextAccessor.HttpContext?.User?.Identity?.IsAuthenticated ?? false)
            {
                //User is logged in -> redirect to the Dashboard page type
                // We need to find the Dashboard page TreeNode we want to redirect to 
                // Im presuming theres just a single Dashboard page on the site here. 
                var dashboardTreeNode = pageRetriever.Retrieve<Dashboard>().FirstOrDefault(); 

                // Then ask kentico what the url it has is
                var dashboardURL = mPageUrlRetriever.Retrieve(dashboardTreeNode).AbsoluteUrl;

                // Then use the standard redirect 
                return Redirect(dashboardURL);
            }
            else
            {
                return View(new HomePageViewModel(currentPage)); //return to the home page view 
            }
        }
    }
}

0 votesVote for this answer Mark as a Correct answer