public void Test_CanThrowIfCancellationRequested()
{
Faker faker = new Faker();
Mock <IQueuedTaskToken> taskMock =
new Mock <IQueuedTaskToken>(MockBehavior.Loose);
using (CancellationTokenSource cts = new CancellationTokenSource())
{
TaskExecutionContext ctx = new TaskExecutionContext(taskMock.Object, cts.Token);
cts.Cancel();
Assert.Throws <OperationCanceledException>(() => ctx.ThrowIfCancellationRequested());
}
}
private async Task<TaskExecutionResult> ExecuteTaskAsync ( TaskExecutionContext executionContext )
{
ITaskExecutor taskExecutor = null;
DateTimeOffset retryAt = DateTimeOffset.UtcNow;
IQueuedTask dequeuedTask = executionContext
.TaskToken
.DequeuedTask;
try
{
//Check for cancellation before we start execution
executionContext.StartTimingExecution();
executionContext.ThrowIfCancellationRequested();
//Attempt to resolve and run task executor
if ( ( taskExecutor = ResolveTaskExecutor( dequeuedTask ) ) != null )
{
mLogger.DebugFormat( "Beginning task execution. Task id = {0}.",
dequeuedTask.Id );
//Execute task
await taskExecutor.ExecuteAsync( dequeuedTask.Payload,
executionContext );
mLogger.DebugFormat( "Task execution completed. Task id = {0}.",
dequeuedTask.Id );
//Ensure we have a result - since no exception was thrown
// and no result explicitly set, assume success.
if ( !executionContext.HasResult )
executionContext.NotifyTaskCompleted();
}
}
catch ( OperationCanceledException )
{
//User code has observed cancellation request
executionContext?.NotifyCancellationObserved();
}
catch ( Exception exc )
{
mLogger.Error( "Error executing queued task",
exception: exc );
bool isRecoverable = mOptions.IsTaskErrorRecoverable( dequeuedTask,
exc );
executionContext?.NotifyTaskErrored( new QueuedTaskError( exc ),
isRecoverable: isRecoverable );
}
finally
{
executionContext.StopTimingExecution();
}
//Compute the amount of time to delay task execution
// if execution failed
if ( executionContext.HasResult
&& executionContext.ExecutionFailed )
retryAt = ComputeRetryAt( executionContext.TaskToken );
return taskExecutor != null
? new TaskExecutionResult( executionContext.ResultInfo,
duration: executionContext.Duration,
retryAt: retryAt,
faultErrorThresholdCount: mOptions.FaultErrorThresholdCount )
: null;
}
