Interface ITrackableTask

Assembly: Alachisoft.NCache.Runtime.dll
Syntax
[Obsolete("This feature is not in active development and may be removed in a future update.")]
public interface ITrackableTask

Properties

TaskId

Unique GUID identification of MapReduce task.

Declaration
string TaskId { get; }
Property Value
Type Description
System.String
Examples

Example prints task id

ITrackableTask taskTracker = cache.ExecuteTask(prodAggregatorTask, new OrderKeyFilter());

Console.WriteLine("Task Id: " + taskTracker.TaskId);

TaskStatus

Gets the task’s status and contains following values: Waiting, InProgress, Completed, Cancelled, Failed.

Declaration
TaskStatus TaskStatus { get; }
Property Value
Type Description
TaskStatus
Examples

Example checks for task status after an interval of 5 seconds

ITrackableTask taskTracker = cache.ExecuteTask(prodAggregatorTask, new OrderKeyFilter());

int count = 0;
do
{
    Thread.Sleep(5000);
    if (count == 2)
    {
        taskTracker.CancelTask();
        break;
    }
    else count++;
} while (taskTracker.TaskStatus.Progress == Alachisoft.NCache.Runtime.MapReduce.TaskStatus.Status.InProgress);

Methods

CancelTask()

Cancels the already running task.

Declaration
void CancelTask()
Examples

Example cancels task if it is not completed in 15 seconds

ITrackableTask taskTracker = cache.ExecuteTask(prodAggregatorTask, new OrderKeyFilter());

int count = 0;
do
{
    Thread.Sleep(5000);
    if (count == 2)
    {
        taskTracker.CancelTask();
        break;
    }
    else count++;
} while (taskTracker.TaskStatus.Progress == Alachisoft.NCache.Runtime.MapReduce.TaskStatus.Status.InProgress);

GetResult()

This is a blocking call that waits for the callback from the server about the task’s completion, failure or cancellation in the form of an ITaskResult.

Declaration
ITaskResult GetResult()
Returns
Type Description
ITaskResult

Returns an ITaskResult instance
Examples

Example gets task result

ITrackableTask taskTracker = cache.ExecuteTask(prodAggregatorTask, new OrderKeyFilter());

ITaskResult result = taskTracker.GetResult();

GetResult(Int32)

If no result is obtained within the provided timeout, OperationFailedException will be thrown.

Declaration
ITaskResult GetResult(int timeout)
Parameters
Type Name Description
System.Int32 timeout

Time in millisecond in which if result is not returned, thread will be terminated and exception or null will be given
Returns
Type Description
ITaskResult

Returns an ITaskResult instance
Examples

Example gets task result with a timeout of 5 seconds

ITrackableTask taskTracker = cache.ExecuteTask(prodAggregatorTask, new OrderKeyFilter());

ITaskResult result = taskTracker.GetResult(5000);

Events

OnMapReduceComplete

Users can register a callback on the MapReduce task that is called when task execution is completed, failed or cancelled with a parameter response that encapsulates status of the task and result (if completed).

Declaration
event MapReduceCallback OnMapReduceComplete
Event Type
Type Description
MapReduceCallback
Examples

Example registers a callback

ITrackableTask taskTracker = cache.ExecuteTask(prodAggregatorTask, new OrderKeyFilter());

taskTracker.OnMapReduceComplete += new MapReduceCallback(MapReduceCompleted);