public void Enqueue(BackgroundTransferEntry entry)
{
lock (Queue)
{
Queue.Enqueue(entry);
}
}
private BackgroundTransferEntry GetNextEntry()
{
lock (Queue)
{
var item = Queue.Dequeue();
CurrentEntry = item;
return(item);
}
}
public void Enqueue(BackgroundTransferEntry transfer)
{
lock (_syncRoot)
{
if (_disposedValue)
{
throw new ObjectDisposedException("_queue");
}
_queue.Enqueue(transfer);
_event.Set();
}
}
/// <inheritdoc />
public async Task EnqueueAsync(IBackgroundTransfer backgroundTransfer, CancellationToken cancellationToken)
{
var sequenceNumber = Interlocked.Increment(ref _sequenceNumber);
var newEntry = new BackgroundTransferEntry(backgroundTransfer, sequenceNumber);
lock (_pendingOrActiveEntries)
{
_pendingOrActiveEntries.Add(newEntry.Id, newEntry);
}
await _channel.Writer
.WriteAsync(newEntry, cancellationToken)
.ConfigureAwait(false);
}
private async Task ExecuteAsync(BackgroundTransferEntry backgroundTransferEntry, CancellationToken cancellationToken)
{
using (_log?.BeginScope(
new Dictionary <string, object>
{
["TransferId"] = backgroundTransferEntry.BackgroundTransfer.TransferId,
}))
{
var backgroundTransfer = backgroundTransferEntry.BackgroundTransfer;
_log?.LogInformation("Starting background transfer {0}", backgroundTransfer.TransferId);
backgroundTransferEntry.Status = BackgroundTransferStatus.Transferring;
// ReSharper disable once AccessToModifiedClosure
var progress = new ActionProgress(sent => backgroundTransferEntry.Transferred = sent);
try
{
await backgroundTransfer.Start(progress, cancellationToken)
.ConfigureAwait(false);
_log?.LogInformation("Completed background transfer {0}", backgroundTransfer.TransferId);
}
catch (Exception ex) when(ex.Is <OperationCanceledException>())
{
// Nothing to do
_log?.LogWarning("Background transfer {0} cancelled", backgroundTransfer.TransferId);
}
catch (Exception ex)
{
// Show the error message
_log?.LogError(ex, "Background transfer {0} faulted", backgroundTransfer.TransferId);
}
finally
{
lock (_pendingOrActiveEntries)
{
_pendingOrActiveEntries.Remove(backgroundTransferEntry.Id);
}
backgroundTransferEntry.Status = BackgroundTransferStatus.Finished;
backgroundTransfer.Dispose();
}
}
}
private void ProcessQueue(CancellationToken cancellationToken)
{
var handles = new[]
{
cancellationToken.WaitHandle,
_event,
};
_log?.LogDebug("Starting background transfer worker.");
try
{
while (!cancellationToken.IsCancellationRequested)
{
var handleIndex = WaitHandle.WaitAny(handles);
if (handleIndex == 0)
{
break;
}
HasData = true;
try
{
BackgroundTransferEntry backgroundTransferEntry;
while ((backgroundTransferEntry = GetNextEntry()) != null)
{
var log = backgroundTransferEntry.Log;
var backgroundTransfer = backgroundTransferEntry.BackgroundTransfer;
try
{
var bt = backgroundTransfer;
log?.LogInformation("Starting background transfer {0}", bt.TransferId);
backgroundTransferEntry.Status = BackgroundTransferStatus.Transferring;
// ReSharper disable once AccessToModifiedClosure
var progress = new ActionProgress(sent => backgroundTransferEntry.Transferred = sent);
var task = bt.Start(progress, cancellationToken);
var cancelledTask = task
.ContinueWith(
t =>
{
// Nothing to do
log?.LogWarning("Background transfer {0} cancelled", bt.TransferId);
},
TaskContinuationOptions.OnlyOnCanceled);
var faultedTask = task
.ContinueWith(
t =>
{
log?.LogError(t.Exception, "Background transfer {0} faulted", bt.TransferId);
},
TaskContinuationOptions.OnlyOnFaulted);
var completedTask = task
.ContinueWith(
t =>
{
// Nothing to do
log?.LogInformation("Completed background transfer {0}", bt.TransferId);
},
TaskContinuationOptions.NotOnCanceled);
try
{
Task.WaitAll(cancelledTask, faultedTask, completedTask);
}
catch (AggregateException ex) when(ex.InnerExceptions.All(x => x is TaskCanceledException))
{
// Ignore AggregateException when it only contains TaskCancelledException
}
log?.LogTrace("Background transfer {0} finished", bt.TransferId);
}
catch (Exception ex)
{
log?.LogError(ex, "Error during execution of background transfer {0}", backgroundTransfer.TransferId);
}
finally
{
backgroundTransfer.Dispose();
}
backgroundTransferEntry.Status = BackgroundTransferStatus.Finished;
CurrentEntry = null;
}
}
finally
{
HasData = false;
}
}
_log?.LogInformation("Cancellation requested - stopping background transfer worker.");
}
finally
{
_log?.LogDebug("Background transfer worker stopped.");
Queue.Dispose();
}
}
private static BackgroundTransferInfo GetInfo(BackgroundTransferEntry entry)
{
return(new BackgroundTransferInfo(entry.Status, entry.BackgroundTransfer.TransferId, entry.Transferred));
}
