/// <summary>
/// Wraps a task with one that will complete as cancelled based on a cancellation token,
/// allowing someone to await a task but be able to break out early by cancelling the token.
/// </summary>
/// <typeparam name="T">The type of value returned by the task.</typeparam>
/// <param name="task">The task to wrap.</param>
/// <param name="cancellationToken">The token that can be canceled to break out of the await.</param>
/// <returns>The wrapping task.</returns>
private static async System.Threading.Tasks.Task <T> WithCancellationSlow <T>(System.Threading.Tasks.Task <T> task, CancellationToken cancellationToken)
{
var tcs = new TaskCompletionSource <bool>();
using (cancellationToken.Register(s => ((TaskCompletionSource <bool>)s).TrySetResult(true), tcs))
{
if (task != await System.Threading.Tasks.Task.WhenAny(task, tcs.Task).ConfigureAwait(false))
{
cancellationToken.ThrowIfCancellationRequested();
}
}
// Rethrow any fault/cancellation exception, even if we awaited above.
// But if we skipped the above if branch, this will actually yield
// on an incompleted task.
return(await task.ConfigureAwait(false));
}
/// <summary>
/// Gets the specified <see cref="CloudTask"/>.
/// </summary>
/// <param name="taskId">The id of the task to get.</param>
/// <param name="detailLevel">A <see cref="DetailLevel"/> used for controlling which properties are retrieved from the service.</param>
/// <param name="additionalBehaviors">A collection of <see cref="BatchClientBehavior"/> instances that are applied to the Batch service request after the <see cref="CustomBehaviors"/> and <paramref name="detailLevel"/>.</param>
/// <param name="cancellationToken">A <see cref="CancellationToken"/> for controlling the lifetime of the asynchronous operation.</param>
/// <returns>A <see cref="CloudTask"/> containing information about the specified Azure Batch task.</returns>
/// <remarks>The get task operation runs asynchronously.</remarks>
public async System.Threading.Tasks.Task <CloudTask> GetTaskAsync(
string taskId,
DetailLevel detailLevel = null,
IEnumerable <BatchClientBehavior> additionalBehaviors = null,
CancellationToken cancellationToken = default(CancellationToken))
{
// throw if if this object is unbound
UtilitiesInternal.ThrowOnUnbound(this.propertyContainer.BindingState);
// craft the behavior manager for this call
BehaviorManager bhMgr = new BehaviorManager(this.CustomBehaviors, additionalBehaviors, detailLevel);
using (System.Threading.Tasks.Task <CloudTask> asyncTask = this.parentBatchClient.JobOperations.GetTaskAsyncImpl(this.Id, taskId, bhMgr, cancellationToken))
{
CloudTask theTask = await asyncTask.ConfigureAwait(continueOnCapturedContext : false);
return(theTask);
}
}
