NamelessG0d

    public class ConcurrentWaitableBag<T> where T : notnull
    {
        private ConcurrentDictionary<T, ManualResetEventSlim> dict = new ConcurrentDictionary<T, ManualResetEventSlim>();

        public bool TryAdd(T item)
        {
            var semaphore = new ManualResetEventSlim(false);
            return dict.TryAdd(item, semaphore);
        }

NamelessG0d

using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.Filters;
using System.Security.Claims;

namespace ASP.Attributes
{
    [AttributeUsage(AttributeTargets.Class | AttributeTargets.Method)]
    public class AccessLevelAttribute : ActionFilterAttribute
    {
        private readonly int _role_level;