/// <inheritdoc />
public override async Task WriteAsync(Message message, CancellationToken cancellationToken)
{
if (message == null)
{
throw new ArgumentNullException(nameof(message));
}
if (DisposalToken.IsCancellationRequested)
{
throw new ObjectDisposedException(nameof(ByLineTextMessageWriter));
}
cancellationToken.ThrowIfCancellationRequested();
DisposalToken.ThrowIfCancellationRequested();
using (var linkedTokenSource =
CancellationTokenSource.CreateLinkedTokenSource(cancellationToken, DisposalToken))
{
var linkedToken = linkedTokenSource.Token;
var content = message.ToString();
await writerSemaphore.WaitAsync(linkedToken);
try
{
await Writer.WriteLineAsync(content);
linkedToken.ThrowIfCancellationRequested();
if (Delimiter != null)
{
await Writer.WriteLineAsync(Delimiter);
linkedToken.ThrowIfCancellationRequested();
}
await Writer.FlushAsync();
}
catch (ObjectDisposedException)
{
// Throws OperationCanceledException if the cancellation has already been requested.
linkedToken.ThrowIfCancellationRequested();
throw;
}
finally
{
if (!DisposalToken.IsCancellationRequested)
{
writerSemaphore.Release();
}
}
}
}
private bool TryTranslateException(Exception exception, CancellationToken cancellationToken1, CancellationToken cancellationToken2)
{
// Consumers treat cancellation due their specified token being cancelled differently from cancellation
// due our instance being disposed. Because we wrap the two in a source, the resulting exception
// contains it instead of the one that was actually cancelled.
if (exception is OperationCanceledException)
{
cancellationToken1.ThrowIfCancellationRequested();
cancellationToken2.ThrowIfCancellationRequested();
}
if (exception is ObjectDisposedException && DisposalToken.IsCancellationRequested)
{
// There's a tiny chance that between checking the cancellation token (wrapping DisposalToken)
// and checking if the underlying SemaphoreSlim has been disposed, that dispose for this instance
// (and hence _semaphore) has been run. Handle that and just treat it as a cancellation.
DisposalToken.ThrowIfCancellationRequested();
}
return(false);
}
