async Task IRetriableStatement.RetryAsync(SpannerRetriableTransaction transaction, CancellationToken cancellationToken, int timeoutSeconds)
{
try
{
await _command.CreateSpannerBatchCommand().ExecuteNonQueryAsync(cancellationToken);
// Fallthrough and throw the exception at the end of the method.
}
catch (SpannerBatchNonQueryException e)
{
// Check that we got the exact same exception and results this time as the previous time.
if (_exception is SpannerBatchNonQueryException batchException &&
e.ErrorCode == _exception.ErrorCode &&
e.Message.Equals(_exception.Message)
// A Batch DML statement returns the update counts of the first N statements and the error
// that occurred for statement N+1.
&& e.SuccessfulCommandResults.SequenceEqual(batchException.SuccessfulCommandResults)
)
{
return;
}
}
catch (SpannerException e) when(e.ErrorCode != ErrorCode.Aborted)
{
// Check that we got the exact same exception during the retry as during the initial attempt.
// This happens if the Batch DML RPC itself failed, and not one of the DML statements.
if (!(_exception is SpannerBatchNonQueryException) && SpannerRetriableTransaction.SpannerExceptionsEqualForRetry(e, _exception))
{
return;
}
}
throw new SpannerAbortedDueToConcurrentModificationException();
}
async Task IRetriableStatement.RetryAsync(SpannerRetriableTransaction transaction, CancellationToken cancellationToken, int timeoutSeconds)
{
_spannerCommand.Transaction = transaction.SpannerTransaction;
var reader = await _spannerCommand.ExecuteReaderAsync(cancellationToken);
int counter = 0;
bool read = true;
byte[] newChecksum = new byte[0];
SpannerException newException = null;
while (read && counter < _numberOfReadCalls)
{
try
{
read = await reader.ReadAsync(cancellationToken);
newChecksum = CalculateNextChecksum(reader, newChecksum, read);
counter++;
}
catch (SpannerException e) when(e.ErrorCode == ErrorCode.Aborted)
{
// Propagate Aborted errors to trigger a new retry.
throw;
}
catch (SpannerException e)
{
newException = e;
counter++;
break;
}
}
if (counter == _numberOfReadCalls &&
newChecksum.SequenceEqual(_currentChecksum) &&
SpannerRetriableTransaction.SpannerExceptionsEqualForRetry(newException, _firstException))
{
// Checksum is ok, we only need to replace the delegate result set if it's still open.
if (IsClosed)
{
reader.Close();
}
else
{
_spannerDataReader = reader;
}
}
else
{
// The results are not equal, there is an actual concurrent modification, so we cannot
// continue the transaction.
throw new SpannerAbortedDueToConcurrentModificationException();
}
}
async Task IRetriableStatement.RetryAsync(SpannerRetriableTransaction transaction, CancellationToken cancellationToken, int timeoutSeconds)
{
try
{
_command.Transaction = transaction.SpannerTransaction;
await _command.ExecuteNonQueryAsync(cancellationToken);
// Fallthrough and throw the exception at the end of the method.
}
catch (SpannerException e) when(e.ErrorCode != ErrorCode.Aborted)
{
// Check that we got the exact same exception this time as the previous time.
if (SpannerRetriableTransaction.SpannerExceptionsEqualForRetry(e, _exception))
{
return;
}
}
throw new SpannerAbortedDueToConcurrentModificationException();
}