ELMAH and API controller in MVC4 not logging errors

Question

Using an API controller in MVC4, when the controller action throws an exception, ELMAH does not log the error.

I think the problem is that MVC4 sets the HTTP status code to 500, and it returns the exception details in a JSON object, but it does not throw an unhandled exception so ELMAH never sees it.

How can I get ELMAH to capture all responses where the status code is not 200?

Answer 1

The anwser described before doesn't work. I've tried on my test server and received an error ("The given filter instance must implement one or more of the following filter interfaces: IAuthorizationFilter, IActionFilter, IResultFilter, IExceptionFilter.")

Then I realized what happened .... you are trying to add the custom filter to the MVC Global Filter (filters.Add(new ElmahHandledErrorLoggerFilter());)

To fix that, I've split the filter registration in GlobalFilter and HttpFilter

FilterConfig.cs

    public static void RegisterGlobalFilters(GlobalFilterCollection filters)
    {
        filters.Add(new HandleErrorAttribute());
    }

    public static void RegisterHttpFilters(HttpFilterCollection filters)
    {
        filters.Add(new ElmahHandledErrorLoggerFilter());
    }

Global.asax

    FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
    FilterConfig.RegisterHttpFilters(GlobalConfiguration.Configuration.Filters);

;-)

Answer 2

UPDATE: This answer does not work in latest versions. Use julianox's answer.

Answer found from information here: http://www.asp.net/web-api/overview/web-api-routing-and-actions/exception-handling

Where the exception filter logs to elmah:

public class ElmahHandledErrorLoggerFilter : ExceptionFilterAttribute
{
    public override void OnException(HttpActionExecutedContext actionExecutedContext)
    {
        base.OnException(actionExecutedContext);

        ErrorSignal.FromCurrentContext().Raise(actionExecutedContext.Exception);
    }
}

but you also have to add the error filter to the GlobalConfiguration filters:

    public static void RegisterGlobalFilters(GlobalFilterCollection filters)
    {
        GlobalConfiguration.Configuration.Filters.Add(new ElmahHandledErrorLoggerFilter());
        filters.Add(new ElmahHandledErrorLoggerFilter());
        filters.Add(new HandleErrorAttribute());
    }