Caching in MVC with Donut Caching - excluding caching login

The main purpose of using caching is to dramatically improve the performance of your application. This is nothing but output caching that means whatever you see is cached, and exact similar things is display to everyone.

I recommend you to read Output Caching in MVC post before you read here, because you should be very careful when using any caching mechanism. Or, if you already know output caching, keep reading here only.

Biggest problem you face

If you display user login status on page which you want to cache, then you need to be careful. With output cache attribute [OutputCache(....)] caches everything on page and it will not exclude caching of some portion like login status.

In the situation, the best caching library you should use is Donut Caching (aka Donut Output Caching). Let’s understand its uses.

Using Donut Caching

The best way to add donut caching to your MVC project is to use the NuGet package. From within Visual Studio, select Tools | Library Package Manager and then choose either Package Manager Console or Manage NuGet Packages. Via the console, just type install-package MvcDonutCaching and hit return. From the GUI, just search for MvcDonutCaching and click the install button.

Excluding from being cached

The package adds several overloads to the built-in Html.Action HTML helper. The extra parameter in each overload is named excludeFromParentCache. Set this to true for any action that should not be cached, or should have a different cache duration from the rest of the page.

@Html.Action("Login", "Account", true)

Here Login is a method inside Account controller, you should define this method like:

public class AccountController : Controller

{

    [ChildActionOnly]

    public ActionResult Login()

    {

        return PartialView("_LoginPartial");

    }

}

Cache rest of the page

The package also include a DonutOutputCacheAttribute to be used in place of the built-in OutputCacheAttribute. This attribute is typically placed on every controller action that needs be be cached.

You can either specify a fixed duration:

[DonutOutputCache(Duration = "300")]

public ActionResult Index()

{

    return View();

}

Or, use a cache profile:

[DonutOutputCache(CacheProfile = "TenMins")]

public ActionResult Index()

{

    return View();

}

If you are using cache profiles, be sure to configure the profiles in the web.config. Add the following within the system.web element:

<caching>

  <outputCacheSettings>

    <outputCacheProfiles>

      <add name="TenMins" duration="400" varyByParam="*" />

    </outputCacheProfiles>

  </outputCacheSettings>

</caching>

You can also configure the output cache to use a custom provider:

<caching>

  <outputCache defaultProvider="DistributedCacheProvider">

    <providers>

      <add name="DistributedCacheProvider" type="DevTrends.Example.DistributedCacheProvider" />

    </providers>

  </outputCache>

</caching>

Note, that a custom provider is not detailed here but you can write one fairly easily by subclassing System.Web.Caching.OutputCacheProvider. A number of implementations are also available on the web.

Hope this helps.