Rent tekniskt så har jag använt mig av ASP.NET MVC, NHibernate och jQuery i en härlig symbios :)

Jag kommer troligtvis skriva fler inlägg om dumbbell.se här i framtiden, men detta får vara tillräckligt för stunden.

So, how do I restrict a method in ASP.NET MVC to be only GET or only POST? I could use ActionFilterAttribute and tag each method with it. But tagging every method is a bit noisy in my opinion. The thing I want is GET to be the default way to access methods, and then I want to mark POST methods only with attributes.

In my MVC projects I always have a BaseController, that all my controllers inherit from. With that in place it is actually quite easy to accomplish the above. I just need to override OnActionExecuting like this:

public class BaseController : Controller
{
    protected override void OnActionExecuting(ActionExecutingContext filterContext)
    {
        var attributes = filterContext.ActionMethod.GetCustomAttributes(
            typeof(POSTAttribute), false);
        var method = filterContext.HttpContext.Request.HttpMethod;
        if (attributes.Length > 0 && method != "POST")
        {
            ThrowIllegalMethodException("POST", filterContext);
        }
        else if (attributes.Length == 0 && method != "GET")
        {
            ThrowIllegalMethodException("GET", filterContext);
        }
    }

    private static void ThrowIllegalMethodException(string expectedHttpMethod,
        ActionExecutingContext filterContext)
    {
        var controllerName = filterContext.Controller.GetType().Name;
        var controllerMethod = filterContext.ActionMethod.Name;
        var httpMethod = filterContext.HttpContext.Request.HttpMethod;

        var message = string.Format("Only {0} method allowed for {1}.{2}, but {3} was used.",
            expectedHttpMethod, controllerName, controllerMethod, httpMethod);
        throw new SecurityException(message);
    }
}

And also I need a POSTAttribute which is simplest possible:

public class POSTAttribute : Attribute
{
}

So, now I can write [POST] above methods like this:

public class MyController : BaseController
{
    [POST]
    public ActionResult SaveMyEntity()
    {
        // Code..
    }
}

Pretty cool that you can change the behaviour of the MVC framework this easy.