internal static async Task <TResponse> CallWithRetryAsync <TResponse>(
this Func <Task <TResponse> > someMethod,
CallSettings callSettings,
IClock clock, IScheduler scheduler)
{
RetrySettings retrySettings = callSettings.Timing?.Retry;
if (retrySettings == null)
{
return(await someMethod().ConfigureAwait(false));
}
DateTime?overallDeadline = retrySettings.TotalExpiration.CalculateDeadline(clock);
TimeSpan retryDelay = retrySettings.RetryBackoff.Delay;
while (true)
{
try
{
return(await someMethod().ConfigureAwait(false));
}
catch (RpcException e) when(retrySettings.RetryFilter(e))
{
TimeSpan actualDelay = retrySettings.DelayJitter.GetDelay(retryDelay);
DateTime expectedRetryTime = clock.GetCurrentDateTimeUtc() + actualDelay;
if (expectedRetryTime > overallDeadline)
{
throw;
}
await scheduler.Delay(actualDelay, callSettings.CancellationToken.GetValueOrDefault()).ConfigureAwait(false);
retryDelay = retrySettings.RetryBackoff.NextDelay(retryDelay);
}
}
}
// TODO: This is a modified/simplified version of ApiCallRetryExtensions.WithRetry from Google.Api.Gax.Grpc. Can we combine them somehow?
internal static async Task RetryOperationUntilCompleted(
Func <Task <bool> > fn,
IClock clock,
IScheduler scheduler,
CallSettings callSettings,
RetrySettings retrySettings)
{
DateTime?overallDeadline = retrySettings.TotalExpiration.CalculateDeadline(clock);
TimeSpan retryDelay = retrySettings.RetryBackoff.Delay;
TimeSpan callTimeout = retrySettings.TimeoutBackoff.Delay;
while (true)
{
DateTime attemptDeadline = clock.GetCurrentDateTimeUtc() + callTimeout;
// Note: this handles a null total deadline due to "<" returning false if overallDeadline is null.
DateTime combinedDeadline = overallDeadline < attemptDeadline ? overallDeadline.Value : attemptDeadline;
CallSettings attemptCallSettings = callSettings.WithCallTiming(CallTiming.FromDeadline(combinedDeadline));
TimeSpan actualDelay = retrySettings.DelayJitter.GetDelay(retryDelay);
DateTime expectedRetryTime;
try
{
bool isResponseOk = await fn().ConfigureAwait(false);
if (isResponseOk)
{
return;
}
expectedRetryTime = clock.GetCurrentDateTimeUtc() + actualDelay;
if (expectedRetryTime > overallDeadline)
{
// TODO: Can we get this string from somewhere?
throw new RpcException(new Status(StatusCode.DeadlineExceeded, "Deadline Exceeded"));
}
}
catch (RpcException e) when(retrySettings.RetryFilter(e))
{
expectedRetryTime = clock.GetCurrentDateTimeUtc() + actualDelay;
if (expectedRetryTime > overallDeadline)
{
throw;
}
}
await scheduler.Delay(actualDelay, callSettings.CancellationToken.GetValueOrDefault()).ConfigureAwait(false);
retryDelay = retrySettings.RetryBackoff.NextDelay(retryDelay);
callTimeout = retrySettings.TimeoutBackoff.NextDelay(callTimeout);
}
}
internal static async Task <TResponse> Retry <TRequest, TResponse>(
Func <TRequest, CallSettings, Task <TResponse> > fn,
TRequest request, CallSettings callSettings, IClock clock, IScheduler scheduler)
{
RetrySettings retrySettings = callSettings.Timing?.Retry;
if (retrySettings == null)
{
return(await fn(request, callSettings).ConfigureAwait(false));
}
DateTime?overallDeadline = retrySettings.TotalExpiration.CalculateDeadline(clock);
TimeSpan retryDelay = retrySettings.RetryBackoff.Delay;
TimeSpan callTimeout = retrySettings.TimeoutBackoff.Delay;
while (true)
{
DateTime attemptDeadline = clock.GetCurrentDateTimeUtc() + callTimeout;
// Note: this handles a null total deadline due to "<" returning false if overallDeadline is null.
DateTime combinedDeadline = overallDeadline < attemptDeadline ? overallDeadline.Value : attemptDeadline;
CallSettings attemptCallSettings = callSettings.WithCallTiming(CallTiming.FromDeadline(combinedDeadline));
try
{
return(await fn(request, attemptCallSettings).ConfigureAwait(false));
}
catch (RpcException e) when(retrySettings.RetryFilter(e))
{
TimeSpan actualDelay = retrySettings.DelayJitter.GetDelay(retryDelay);
DateTime expectedRetryTime = clock.GetCurrentDateTimeUtc() + actualDelay;
if (expectedRetryTime > overallDeadline)
{
throw;
}
await scheduler.Delay(actualDelay, callSettings.CancellationToken.GetValueOrDefault()).ConfigureAwait(false);
retryDelay = retrySettings.RetryBackoff.NextDelay(retryDelay);
callTimeout = retrySettings.TimeoutBackoff.NextDelay(callTimeout);
}
}
}