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    <p>First, thanks for the link to the post <a href="http://lostechies.com/jimmybogard/2013/10/29/put-your-controllers-on-a-diet-gets-and-queries/">"Put your controllers on a diet: GETs and queries"</a>. My code example uses types from it.</p> <p>My solution <strong>also involves usage of action filters</strong> as point to inject generic behaviour.</p> <p>Controller is simple enough and looks like @Kambiz Shahim's:</p> <pre><code>[QueryFilter] public class ConferenceController : Controller { public ActionResult Index(IndexQuery query) { return View(); } public ViewResult Show(ShowQuery query) { return View(); } public ActionResult Edit(EditQuery query) { return View(); } } </code></pre> <p>Working on <code>QueryFilterAttribute</code> I realised that <strong><code>IMediator</code> and its implementation can be omitted. It is enough to know type of query to resolve an instance of <code>IQueryHandler&lt;,&gt;</code> via IoC.</strong></p> <p>In my example <a href="http://docs.castleproject.org/Windsor.MainPage.ashx">Castle Windsor</a> and implementation of <a href="http://blog.ploeh.dk/2010/02/03/ServiceLocatorisanAnti-Pattern/">'Service Locator'</a> pattern are used.</p> <pre><code>public class QueryFilterAttribute : ActionFilterAttribute { public override void OnActionExecuting(ActionExecutingContext filterContext) { base.OnActionExecuting(filterContext); object query = filterContext.ActionParameters["query"]; Type queryType = query.GetType(); Type modelType = queryType.GetInterfaces()[0].GetGenericArguments()[0]; var handlerType = typeof(IQueryHandler&lt;,&gt;).MakeGenericType(queryType, modelType); // Here you should resolve your IQueryHandler&lt;,&gt; using IoC // 'Service Locator' pattern is used as quick-and-dirty solution to show that code works. var handler = ComponentLocator.GetComponent(handlerType) as IQueryHandler; var model = handler.Handle(query); filterContext.Controller.ViewData.Model = model; } } </code></pre> <p><code>IQueryHandler</code> interface is added to avoid working with Reflection</p> <pre><code>/// &lt;summary&gt; /// All derived handlers can be refactored using generics. But in the real world handling logic can be completely different. /// &lt;/summary&gt; /// &lt;typeparam name="TQuery"&gt;The type of the query.&lt;/typeparam&gt; /// &lt;typeparam name="TResponse"&gt;The type of the response.&lt;/typeparam&gt; public interface IQueryHandler&lt;in TQuery, out TResponse&gt; : IQueryHandler where TQuery : IQuery&lt;TResponse&gt; { TResponse Handle(TQuery query); } /// &lt;summary&gt; /// This interface is used in order to invoke 'Handle' for any query type. /// &lt;/summary&gt; public interface IQueryHandler { object Handle(object query); } /// &lt;summary&gt; /// Implements 'Handle' of 'IQueryHandler' interface explicitly to restrict its invocation. /// &lt;/summary&gt; /// &lt;typeparam name="TQuery"&gt;The type of the query.&lt;/typeparam&gt; /// &lt;typeparam name="TResponse"&gt;The type of the response.&lt;/typeparam&gt; public abstract class QueryHandlerBase&lt;TQuery, TResponse&gt; : IQueryHandler&lt;TQuery, TResponse&gt; where TQuery : IQuery&lt;TResponse&gt; { public abstract TResponse Handle(TQuery query); object IQueryHandler.Handle(object query) { return Handle((TQuery)query); } } </code></pre> <p>Types should be registered <code>in Global.asax.cs</code></p> <pre><code> container.Register(Component.For&lt;ISession&gt;().ImplementedBy&lt;FakeSession&gt;()); container.Register( Classes.FromThisAssembly() .BasedOn(typeof(IQueryHandler&lt;,&gt;)) .WithService.Base() .LifestylePerWebRequest()); </code></pre> <p>There is a <a href="https://gist.github.com/ilyapalkin/c82904208bd529814713"><strong>link to gist on github</strong></a> with all code.</p>
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    1. COYeah does make it easier to just remove the mediator.
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