some.fs

module Infrastructure.Web.Api.Mvc
open Microsoft.AspNetCore.Mvc.Filters
open Microsoft.Extensions.Logging
open Infrastructure.Web.Api.Localization
open System
open Microsoft.AspNetCore.Mvc
 
let (|NotNull|) name = function
    | null -> nullArg name
    | o    -> o

let inline is<'a> a =
    match box a with
    | :? 'a as a -> Some a
    | _ -> None
 
type OperationCanceledExceptionFilter(logger) =
    inherit ExceptionFilterAttribute(logger)
    let (NotNull "logger" logger) = logger
    
    override this.OnException (context : ExceptionContext) =
        is<OperationCanceledException> context
        |> Option.iter (fun _ ->
            this.logger.LogInformation(Resources.RequestWasCancelled)
            context.ExceptionHandled <- true
            context.Result <- StatusCodeResult(499))