public Task<IListener> CreateAsync(ListenerFactoryContext context)
 {
     IListener listener = new NullListener();
     return Task.FromResult(listener);
 }
        public Task <IListener> CreateAsync(IFunctionExecutor executor, CancellationToken cancellationToken)
        {
            IListener listener = new NullListener();

            return(Task.FromResult(listener));
        }
 public Task<IListener> CreateAsync(CancellationToken cancellationToken)
 {
     IListener listener = new NullListener();
     return Task.FromResult(listener);
 }