/// <summary>Run the pump until the inner iterator is done, an error occurs, or the cancellation token is fired</summary>
public async Task PumpAsync(CancellationToken ct)
{
if (m_state != STATE_IDLE)
{
if (m_state >= STATE_FAILED)
{
throw new InvalidOperationException("The iterator pump has already completed once");
}
else
{
throw new InvalidOperationException("The iterator pump is already running");
}
}
try
{
while (!ct.IsCancellationRequested)
{
LogDebug("waiting for next");
m_state = STATE_WAITING_FOR_NEXT;
if (!(await m_iterator.MoveNextAsync(ct).ConfigureAwait(false)))
{
LogDebug("completed");
m_state = STATE_DONE;
m_target.OnCompleted();
return;
}
LogDebug("got item, publishing...");
m_state = STATE_PUBLISHING_TO_TARGET;
await m_target.OnNextAsync(m_iterator.Current, ct).ConfigureAwait(false);
}
// push the cancellation on the queue
OnError(ExceptionDispatchInfo.Capture(new OperationCanceledException(ct)));
// and throw!
}
catch (Exception e)
{
LogDebug("failed... (" + m_state + ") : " + e.Message);
if (m_state == STATE_FAILED)
{ // already signaled the target, just throw
throw;
}
// push the error on the queue, and eat the error
OnError(ExceptionDispatchInfo.Capture(e));
}
finally
{
if (m_state != STATE_FAILED)
{
m_state = STATE_DONE;
}
LogDebug("stopped (" + m_state + ")");
}
}
public Task <bool> MoveNextAsync(CancellationToken cancellationToken)
{
return(m_iterator.MoveNextAsync(cancellationToken));
}