ASP.NET doesn’t provide a native way of donut output caching, so we must resort to a great NuGet package called MVCDonutCaching. You can read all about it here: http://www.devtrends.co.uk/blog/donut-output-caching-in-asp.net-mvc-3.

Since Umbraco is built on top of ASP.NET MVC, we can easily use this package on our websites. There are, however, some caveats, because Umbraco doesn’t use the native MVC routing.

For Umbraco, every page that uses the same document type is processed through the same route, therefore, if we have 100 news articles that use the NewsItem document type, from the moment we open one news article page, every other news item page will display the same information, despite having a different URL!

The way to bypass this issue is the following:

Create a Global.cs file that includes the logic to cache a page based on their url and not the document type

namespace CreateIT.Web
{
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Web;
    using Umbraco.Web;

    public class Global : UmbracoApplication
    {
        public override string GetVaryByCustomString(HttpContext context, string custom)
        {
            if (custom.ToLower() == "url")
            {
                return "url=" + context.Request.Url.AbsoluteUri;
            }

            return base.GetVaryByCustomString(context, custom);
        }
    }
}

Then, instruct Umbraco to use this class when launching the UmbracoApplication by changing the Global.asax file:

<%@ Application Codebehind="Global.cs" Inherits="CreateIT.Web.Global" Language="C#" %>

Finally, setup an Output Cache profile in your Web.config:

<system.web>
    (...)
    <caching>
      <outputCacheSettings>
        <outputCacheProfiles>
          <add enabled="true" name="CreateIT.Actions" duration="900" location="Server" varyByCustom="url" varyByParam="*" />
        </outputCacheProfiles>
      </outputCacheSettings>
    </caching>
</system.web>

And decorate the chosen controllers (that you used to hijack the Umbraco routes) with the Donut Output Cache attribute:

[DonutOutputCache(CacheProfile = "CreateIT.Actions")]
public class HomepageController : Umbraco.Web.Mvc.RenderMvcController
{

If you wish to exclude a certain part of your page from the cache, just create a Surface Controller action that returns a partial view and use the extension method provided by MVCDonutCaching for @Html.Action().

The post Umbraco and Donut Output Cache appeared first on Blog IT.

I need this model to be filled before the action result, so that I can use those properties on the view.

In order to do this, I created a custom Action Filter Attribute that is used by every action:

    public class SetupMasterModelActionFilter : ActionFilterAttribute
    {
        public override void OnActionExecuted(ActionExecutedContext filterContext)
        {
            ViewResultBase result = filterContext.Result as ViewResultBase;
            if (result == null)
            {
                return;
            }

            MasterModel model = result.Model as MasterModel;
            if (model == null)
            {
                return;
            }

            SetupMasterModel(model);
            SetupViewBag(result, model);
        }

        private void SetupMasterModel(MasterModel model)
        {
            ...
        }

        private void SetupViewBag(ViewResultBase result, MasterModel model)
        {
            ...
        }
   }

In order to execute this filter before every action I had to register it in the GlobalFilters at the Global.asax.cs file:

        protected void Application_Start()
        {
            AreaRegistration.RegisterAllAreas();

            GlobalFilters.Filters.Add(new SetupMasterModelActionFilter());

            RouteConfig.RegisterRoutes(RouteTable.Routes);
        }

There are, however, some pages that don’t use this master model, so I need to exclude the use of this filter on certain actions. In order to do this, I created a new Filter Provider that looks for an exclude filter and filters out the one targeted:

    public class ExcludeFilterProvider : IFilterProvider
    {
        private FilterProviderCollection filterProviders;

        public ExcludeFilterProvider(IFilterProvider[] filters)
        {
            this.filterProviders = new FilterProviderCollection(filters);
        }

        public IEnumerable<Filter> GetFilters(ControllerContext controllerContext, ActionDescriptor actionDescriptor)
        {
            Filter[] filters = this.filterProviders.GetFilters(controllerContext, actionDescriptor).ToArray();

            IEnumerable<ExcludeFilterAttribute> excludeFilters = (from f in filters where f.Instance is ExcludeFilterAttribute select f.Instance as ExcludeFilterAttribute);

            List<Type> filterTypesToRemove = new List<Type>();
            foreach (ExcludeFilterAttribute excludeFilter in excludeFilters)
            {
                filterTypesToRemove.Add(excludeFilter.FilterType);
            }

            IEnumerable<Filter> res = (from filter in filters where !filterTypesToRemove.Contains(filter.Instance.GetType()) select filter);
            return res;
        }
    }

The exclude filter attribute that will decorate the excluded actions:

    public class ExcludeFilterAttribute : FilterAttribute
    {
        private Type filterType;

        public ExcludeFilterAttribute(Type filterType)
        {
            this.filterType = filterType;
        }

        public Type FilterType
        {
            get
            {
                return this.filterType;
            }
        }
    } 

And we add the new provider at the start of the application and remove the old ones:

        protected void Application_Start()
        {
            AreaRegistration.RegisterAllAreas();

            GlobalFilters.Filters.Add(new SetupMasterModelActionFilter());

            IFilterProvider[] providers = FilterProviders.Providers.ToArray();
            FilterProviders.Providers.Clear();
            FilterProviders.Providers.Add(new ExcludeFilterProvider(providers));

            RouteConfig.RegisterRoutes(RouteTable.Routes);
        }

With this, every action will setup the master model properties except the ones that implement the exclude filter:

    public class HomeController : Controller
    {
        [ExcludeFilter(typeof(SetupMasterModelActionFilter))]
        public ActionResult Index()
        {
            HomeModel model = new HomeModel();

            return View(model);
        }
    }

The post Pre-set common viewmodel properties before action result appeared first on Blog IT.