public async Task <bool> HandleInvalidationAsync(CacheInvalidationEvent invalidationEvent)
        {
            if (invalidationEvent.InstanceId == _instanceId)
            {
                return(true);
            }

            return((await Task.WhenAll(_handlers.Select(x => x(invalidationEvent))).ConfigureAwait(false)).All(x => x));
        }
 protected abstract Task <bool> SendInvalidationAsync(CacheInvalidationEvent invalidationEvent);