internal Task <bool> MoveTransmissionsAndWaitForSender(CancellationToken cancellationToken)
{
if (cancellationToken.IsCancellationRequested)
{
return(TaskEx.FromCanceled <bool>(cancellationToken));
}
TaskStatus senderStatus = TaskStatus.Canceled;
bool isStorageEnqueueSuccess = false;
try
{
this.Storage.IncrementFlushAsyncCounter();
isStorageEnqueueSuccess = MoveTransmissions(this.Buffer.Dequeue, this.Storage.Enqueue, this.Buffer.Size, cancellationToken);
TelemetryChannelEventSource.Log.MovedFromBufferToStorage();
senderStatus = this.Sender.WaitForPreviousTransmissionsToComplete(cancellationToken).ConfigureAwait(false).GetAwaiter().GetResult();
}
catch (Exception exp)
{
senderStatus = TaskStatus.Faulted;
TelemetryChannelEventSource.Log.TransmissionFlushAsyncWarning(exp.ToString());
}
finally
{
this.Storage.DecrementFlushAsyncCounter();
}
if (senderStatus == TaskStatus.Canceled)
{
return(TaskEx.FromCanceled <bool>(cancellationToken));
}
return(senderStatus == TaskStatus.RanToCompletion && isStorageEnqueueSuccess ? this.successTask : this.failedTask);
}
public static void TaskExGenericFromCanceledIsCanceled()
{
using (var source = new CancellationTokenSource())
{
source.Cancel();
var task = TaskEx.FromCanceled <bool>(source.Token);
Assert.IsTrue(task.IsCanceled);
}
}
/// <summary>
/// Asynchronously flushes the telemetry buffer.
/// </summary>
/// <returns>
/// Returns true when telemetry data is transferred out of process (application insights server or local storage) and are emitted before the flush invocation.
/// Returns false when transfer of telemetry data to server has failed with non-retriable http status code.
/// </returns>
public Task <bool> FlushAsync(CancellationToken cancellationToken)
{
if (!this.isInitialized)
{
TelemetryChannelEventSource.Log.StorageNotInitializedError();
}
TelemetryChannelEventSource.Log.TelemetryChannelFlushAsync();
return(cancellationToken.IsCancellationRequested ? TaskEx.FromCanceled <bool>(cancellationToken) : this.TelemetryBuffer.FlushAsync(cancellationToken));
}
/// <summary>
/// Passes all <see cref="ITelemetry"/> items to the <see cref="TelemetrySerializer"/>, empties the queue and returns a task.
/// </summary>
public virtual Task <bool> FlushAsync(CancellationToken cancellationToken)
{
List <ITelemetry> telemetryToFlush = this.GetBufferTelemetryAndResetBuffer();
if (!cancellationToken.IsCancellationRequested)
{
return(this.serializer.SerializeAsync(telemetryToFlush, cancellationToken));
}
return(TaskEx.FromCanceled <bool>(cancellationToken));
}
internal Task <bool> FlushAsync(Transmission transmission, CancellationToken cancellationToken)
{
TaskStatus taskStatus = TaskStatus.Canceled;
if (!cancellationToken.IsCancellationRequested)
{
transmission.IsFlushAsyncInProgress = true;
this.Enqueue(transmission);
try
{
this.Storage.IncrementFlushAsyncCounter();
taskStatus = this.MoveTransmissionsAndWaitForSender(transmission.FlushAsyncId, cancellationToken);
}
catch (Exception exp)
{
taskStatus = TaskStatus.Faulted;
TelemetryChannelEventSource.Log.TransmissionFlushAsyncWarning(exp.ToString());
}
finally
{
this.Storage.DecrementFlushAsyncCounter();
}
}
Task <bool> flushTaskStatus = null;
if (taskStatus == TaskStatus.Canceled)
{
flushTaskStatus = TaskEx.FromCanceled <bool>(cancellationToken);
}
else if (taskStatus == TaskStatus.RanToCompletion && transmission.IsFlushAsyncInProgress)
{
flushTaskStatus = this.successTask;
}
else
{
flushTaskStatus = this.failedTask;
}
return(flushTaskStatus);
}
private async Task <string> ReceiveLoopAsync(BufferingContext bufferingContext, CancellationToken cancellationToken, int loop)
{
using (bufferingContext)
{
var encoding = bufferingContext.Encoding;
var bufferBytes = bufferingContext.BufferBytes;
var bufferChars = bufferingContext.BufferChars;
var sb = bufferingContext.StringBuilder;
try
{
string response = null;
while ((loop == -1 || --loop >= 0) && !cancellationToken.IsCancellationRequested)
{
response = await ReceiveMessageAsync(cancellationToken, bufferBytes, bufferChars, encoding, sb);
sb = sb.Clear();
}
if (cancellationToken.IsCancellationRequested)
{
return(await TaskEx.FromCanceled <string>(cancellationToken));
}
return(response);
}
catch (AggregateException ex)
{
ErrorReceived?.Invoke(this, new SocketErrorEventArgs {
Exception = ex.Flatten()
});
}
catch (Exception ex)
{
ErrorReceived?.Invoke(this, new SocketErrorEventArgs {
Exception = ex
});
}
}
return(await Task.FromResult(string.Empty));
}
/// <summary>
/// Creates a new entry and queues it to this wait queue. If the cancellation token is already canceled, this method immediately returns a canceled task without modifying the wait queue.
/// </summary>
/// <param name="this">The wait queue.</param>
/// <param name="mutex">A synchronization object taken while cancelling the entry.</param>
/// <param name="token">The token used to cancel the wait.</param>
/// <returns>The queued task.</returns>
public static Task <T> Enqueue <T>(this IAsyncWaitQueue <T> @this, object mutex, CancellationToken token)
{
if (token.IsCancellationRequested)
#if NET451
{ return(TaskEx.FromCanceled <T>(token)); }
#else
{ return(Task.FromCanceled <T>(token)); }
#endif
var ret = @this.Enqueue();
if (!token.CanBeCanceled)
{
return(ret);
}
var registration = token.Register(() =>
{
lock (mutex)
@this.TryCancel(ret, token);
}, useSynchronizationContext: false);
ret.ContinueWith(_ => registration.Dispose(), CancellationToken.None, TaskContinuationOptions.ExecuteSynchronously, TaskScheduler.Default);
return(ret);
}
private Task <string> ReceiveLoopAsync(BufferingContext bufferingContext, CancellationToken cancellationToken, int loop)
{
string response = null;
return(TaskEx.AsyncLoopTask(() =>
{
cancellationToken.ThrowIfCancellationRequested();
if (loop == -1 || --loop >= 0)
{
return TaskEx.FromResult(Flow <string> .Return(response));
}
var encoding = bufferingContext.Encoding;
var bufferBytes = bufferingContext.BufferBytes;
var bufferChars = bufferingContext.BufferChars;
var sb = bufferingContext.StringBuilder;
return ReceiveMessageAsync(cancellationToken, bufferBytes, bufferChars, encoding, sb).ContinueWith(t =>
{
response = t.Result;
sb.Length = 0;
return Flow <string> .Continue();
}, cancellationToken);
}).ContinueWithTask(task =>
{
if (cancellationToken.IsCancellationRequested)
{
return TaskEx.FromCanceled <string>(cancellationToken);
}
return TaskEx.FromResult(task.Result);
}, cancellationToken)
.CatchWith <string, Exception>(ex => ErrorReceived?.Invoke(this, new SocketErrorEventArgs {
Exception = ex
}))
.UsingWith(bufferingContext));
}
public static void TaskExGenericFromCanceledThrowsOnNonCanceledToken()
{
Assert.Throws <ArgumentOutOfRangeException, Task <bool> >(() => TaskEx.FromCanceled <bool>(CancellationToken.None));
}
