/// <summary>
/// Clears task and unsubscribes from current worker channel events.
/// </summary>
private void DiscardTask()
{
Contract.Requires(currentTask != null);
Contract.Requires(currentTask.Worker == this);
Contract.Ensures(currentTask == null);
try
{
var operationContext = OperationContext.Current;
operationContext.Channel.Closing -= OnChannelClosing;
operationContext.Channel.Faulted -= OnChannelFaulted;
currentTask.Worker = null;
currentTask = null;
}
catch
{ }
}
/// <summary>
/// Request a task for execution.
/// </summary>
/// <returns>
/// Blocks current thread until a task will be available for execution.
/// </returns>
public Task GetTask()
{
Contract.Requires<InvalidOperationException>(currentTask == null);
var timeout = OperationContext.Current.Channel.OperationTimeout.Subtract(TimeSpan.FromMilliseconds(100));
currentTask = taskQueue.PickTask(this, timeout);
if (currentTask != null)
{
Logger.Write(
LogCategories.Information(string.Format("Task {0} assigned to {1}", currentTask, RemoteAddress),
LogCategories.TaskServices,
LogCategories.TaskProviderService));
Trace.WriteLine(string.Format("Task {0} is assigned", currentTask));
AssignTask();
return currentTask.ToContract();
}
return null;
}
