private async IAsyncEnumerable <string> GetOutput(Guid id, OutputType type, [EnumeratorCancellation] CancellationToken cancellationToken)
{
var output = _outputService.GetOutput(id);
if (output == null)
{
string dbOutput = await this.GetDbOutput(id, type, cancellationToken);
yield return(dbOutput);
yield break;
}
var resetEvent = output.Subscribe();
var sent = string.Empty;
bool done = false;
do
{
if (output.Complete)
{
done = true;
}
var newContent = output.Content.Substring(sent.Length);
yield return(newContent);
sent += newContent;
if (!done)
{
try
{
await resetEvent.WaitAsync(cancellationToken);
}
catch (TaskCanceledException)
{
done = true;
}
}
}while (!done);
output.Unsubscribe(resetEvent);
}
