How to intercept filterchain for maintenance in a WebApi project

Question

I have a WebApi project, where I want to implement a maintenancefilter. Now, I have the problem, that the filter is called twice. So I got the correct http statuscode, but the filter don't intercept and my methods in the controlled are called, normally.

What I have to do, that my filter intercepts correctly and no other method is called?

public class MaintenanceFilter : ActionFilterAttribute
{
    [Dependency]
    public IUaCRepository UaC { get; set; }

    public override void OnActionExecuting(HttpActionContext actionContext)
    {
        base.OnActionExecuting(actionContext);
    }

    public override void OnActionExecuted(HttpActionExecutedContext actionExecutedContext)
    {
        if (UaC != null && UaC.CheckMaintenance(WebApiConfig.CONFIG_STANDARD))
        {
            var response = actionExecutedContext.Response;
            response.StatusCode = HttpStatusCode.ServiceUnavailable;

            return;
        }
        base.OnActionExecuted(actionExecutedContext);
    }
}

best regards

[EDIT] This soleved my problem:

    public override void OnActionExecuting(HttpActionContext actionContext)
    {
        if (UaC != null && UaC.CheckMaintenance(WebApiConfig.CONFIG_STANDARD))
        {
            actionContext.Response = actionContext.Request.CreateErrorResponse(HttpStatusCode.ServiceUnavailable, "Maintenance");

            return;
        }
        base.OnActionExecuting(actionContext);
    }

Answer 1

Override the OnActionExecuting method providing the fixed response. In this way it will not go on to with the request processing

public override void OnActionExecuting(HttpActionContext actionContext)
    {
        if (UaC != null && UaC.CheckMaintenance(WebApiConfig.CONFIG_STANDARD))
        {
            actionContext.Response = actionContext.Request.CreateErrorResponse(HttpStatusCode.ServiceUnavailable, "Maintenance");

            return;
        }
        base.OnActionExecuting(actionContext);
    }