public RetryingHandler(TimeSpan timeout, TimeSpan uploadTimeout, int maxRetries, Func <int, DelegateResult <HttpResponseMessage>, Context, TimeSpan> sleepDurationProvider)
{
AsyncRetryPolicy <HttpResponseMessage> retryAfterPolicy = Policy
.HandleResult <HttpResponseMessage>(ContainsRetryAfterHeader)
.WaitAndRetryAsync(maxRetries, sleepDurationProvider, (outcome, timespan, retryCount, context) => Task.CompletedTask);
AsyncRetryPolicy <HttpResponseMessage> httpRetryPolicy =
Policy
.Handle <HttpRequestException>()
.Or <TaskCanceledException>()
.Or <TimeoutRejectedException>()
.OrResult <HttpResponseMessage>(RetryRequired)
.WaitAndRetryAsync(GetBackOff(maxRetries));
AsyncPolicyWrap <HttpResponseMessage> baseRetryPolicy = retryAfterPolicy.WrapAsync(httpRetryPolicy);
_policy = baseRetryPolicy.WrapAsync(Policy.TimeoutAsync(timeout));
_fileUploadPolicy = baseRetryPolicy.WrapAsync(Policy.TimeoutAsync(uploadTimeout));
}