private async Task <Metadata> GetResponseHeadersCoreAsync()
{
try
{
var httpResponse = await HttpResponseTask.ConfigureAwait(false);
// Check if the headers have a status. If they do then wait for the overall call task
// to complete before returning headers. This means that if the call failed with a
// a status then it is possible to await response headers and then call GetStatus().
var grpcStatus = GrpcProtocolHelpers.GetHeaderValue(httpResponse.Headers, GrpcProtocolConstants.StatusTrailer);
if (grpcStatus != null)
{
await CallTask.ConfigureAwait(false);
}
var metadata = GrpcProtocolHelpers.BuildMetadata(httpResponse.Headers);
// https://github.com/grpc/proposal/blob/master/A6-client-retries.md#exposed-retry-metadata
if (_attemptCount > 1)
{
metadata.Add(GrpcProtocolConstants.RetryPreviousAttemptsHeader, (_attemptCount - 1).ToString(CultureInfo.InvariantCulture));
}
return(metadata);
}
catch (Exception ex) when(ResolveException(ErrorStartingCallMessage, ex, out _, out var resolvedException))
{
throw resolvedException;
}
}
private async Task <Metadata> GetResponseHeadersCoreAsync()
{
try
{
var httpResponse = await HttpResponseTask.ConfigureAwait(false);
// Check if the headers have a status. If they do then wait for the overall call task
// to complete before returning headers. This means that if the call failed with a
// a status then it is possible to await response headers and then call GetStatus().
var grpcStatus = GrpcProtocolHelpers.GetHeaderValue(httpResponse.Headers, GrpcProtocolConstants.StatusTrailer);
if (grpcStatus != null)
{
await CallTask.ConfigureAwait(false);
}
var metadata = GrpcProtocolHelpers.BuildMetadata(httpResponse.Headers);
// https://github.com/grpc/proposal/blob/master/A6-client-retries.md#exposed-retry-metadata
if (_attemptCount > 1)
{
metadata.Add(GrpcProtocolConstants.RetryPreviousAttemptsHeader, (_attemptCount - 1).ToString(CultureInfo.InvariantCulture));
}
return(metadata);
}
catch (Exception ex)
{
// If there was an error fetching response headers then it's likely the same error is reported
// by response TCS. The user is unlikely to observe both errors.
// Observe the task's exception to prevent TaskScheduler.UnobservedTaskException from firing.
_responseTcs?.Task.ObserveException();
if (ResolveException(ErrorStartingCallMessage, ex, out _, out var resolvedException))
{
throw resolvedException;
}
else
{
throw;
}
}
}
