ItemResolvers not working as expected

Question

Using Sitecore 8.1

I have two custom ItemResolvers in my site, in this order:

• ItemResolver (The sitecore default)
• ProductItemResolver (Determines if a product exists for a wildcard item)
• NotFoundItemResolver (Sets a default item, if no item has been set)

The code is as follows:

ProductItemResolver.cs:

/// <summary>
/// Based on https://superruub.wordpress.com/2012/07/30/sitecore-wildcard-404-page/
/// </summary>
public class ProductItemResolver : HttpRequestProcessor
{
    public override void Process(HttpRequestArgs args)
    {
        Profiler.StartOperation("Resolve product item");
        Assert.ArgumentNotNull(args, "args");
        if (((Context.Item != null && Context.Item.Name == "*") && (Context.Database != null))
            && (args.Url.ItemPath.Length != 0)
            && Context.Item.TemplateID == SitecoreConstants.Templates.Product.Id)
        {
            //Fetch product from elastic
            var productId = args.Context.Request.Url.GetProductId();
            var catalogService = ObjectFactory.Instance.Resolve<ICatalogService>();
            var productExists = catalogService.ProductExists(productId);

            //If it is null, set Context.Item to null to trigger NotFound flow
            if (!productExists)
            {
                Context.Item = null;
            }
        }
        Profiler.EndOperation();
    }
}

NotFoundItemResolver:

/// <summary>
/// Based on https://laubplusco.net/handling-404-sitecore-avoid-302-redirects/
/// </summary>
public class NotFoundItemResolver : HttpRequestProcessor
{
    public override void Process(HttpRequestArgs args)
    {
        //Check if we even need to hande this
        if (IsValidContextItemResolved()
            || args.LocalPath.StartsWith("/sitecore")
            || args.Url.FilePath.StartsWith("/sitecore")
            || RequestIsForPhysicalFile(args.Url.FilePath))
            return;

        var siteSettingsProvider = ObjectFactory.Instance.Resolve<ISiteSettingsProvider>();
        ISiteSettings siteSettings = siteSettingsProvider.Get();

        if (siteSettings.NotFoundItem == null
            || siteSettings.NotFoundItem.Empty
            || !siteSettings.NotFoundItem.HasContextLanguage())
            return;

        Context.Item = siteSettings.NotFoundItem;
    }

    protected virtual bool IsValidContextItemResolved()
    {
        if (Context.Item == null || !Context.Item.HasContextLanguage())
            return false;
        return !(Context.Item.Visualization.Layout == null && string.IsNullOrEmpty(WebUtil.GetQueryString("sc_layout")));
    }

    protected virtual bool RequestIsForPhysicalFile(string filePath)
    {
        return File.Exists(HttpContext.Current.Server.MapPath(filePath));
    }
}

The NotFound item has a controller configured on the standardvalues of its template.

public class NotFoundController : BaseController
{
    // GET
    public override ActionResult Index()
    {
        Response.StatusCode = (int) HttpStatusCode.NotFound;
        return View("~/Views/Shared/Core/NotFound.cshtml");
    }
}

Now, if I hit a url where sitecore does not find an item, I get what I expect. I hit my NotFound controller, and render my NotFound view.

But if Sitecore resolves the wildcard item, and I set the Context.Item = null in the ProductItemResolver, then I get the layout from the wildcard item rendered, and the Context.Item.Name in the .cshtml file returns "*". Even though I just changed the item.

But the http status code of the response is 404.

What is going on here? Am I hitting some sort of caching issue?

Answer 1

Sitecore MVC resolves it (again)

Which is both confusing and (I find) a little odd. But here's what's happening.

You patch after the regular ItemResolver and do your custom work. And you assume all is well from that point on. And normally it would be.

But Sitecore MVC adds a series of steps to the pipeline (for MVC requests, obviously), one of them being an execution of the mvc.getPageItem pipeline to build up the MVC-specific context class Sitecore.Mvc.Presentation.PageContext.

And mvc.getPageItem (you probably guessed it), sets a new value in Sitecore.Context.Page.

To work around this behaviour, one of the easiest approaches is to indicate (on HttpContext.Items for instance) that your processor has done work, and then check for this value at the end of the mvc.GetPageItem processor.

For previous and current Sitecore versions, @JammyKam has a full write up on his blog:

• Resolving Custom Context.Item in Sitecore MVC