/// <summary>
/// Handles the specified message.
/// </summary>
/// <typeparam name="T">the type of the message.</typeparam>
/// <param name="workGroup">The work group.</param>
/// <param name="message">The message.</param>
/// <param name="notifications">The notifications.</param>
/// <param name="functionToRun">The function to run.</param>
/// <param name="taskFactory">The task factory.</param>
/// <returns></returns>
public Task HandleAsync <T>(IWorkGroup workGroup, IReceivedMessage <T> message, IWorkerNotification notifications, Action <IReceivedMessage <T>, IWorkerNotification> functionToRun, ITaskFactory taskFactory)
where T : class
{
Guard.NotNull(() => message, message);
Guard.NotNull(() => notifications, notifications);
Guard.NotNull(() => functionToRun, functionToRun);
Guard.NotNull(() => taskFactory, taskFactory);
while (true)
{
//verify that we are not canceling or stopping before trying to queue the item
//however, the transport must support rollbacks
if (!ShouldHandle(notifications))
{
return(null);
}
if (taskFactory.TryStartNew(state => { WrappedFunction(message, notifications, functionToRun); }, new StateInformation(workGroup), task =>
{
if (task.IsFaulted && task.Exception?.InnerException is OperationCanceledException)
{
//bubble the cancel exception; the queue will rollback the message if possible
throw new OperationCanceledException("user canceled", task.Exception.InnerException); //explicitly throw this
}
if (task.IsFaulted && task.Exception != null)
{
//need to throw it
throw new DotNetWorkQueueException("Message processing exception", task.Exception.InnerException);
}
}, out var start).Success())
{
try
{
return(start);
}
finally
{
//block here if the scheduler is full
try
{
_waitingOnFreeThreadCounter.Increment();
taskFactory.Scheduler.WaitForFreeThread.Wait(workGroup);
}
finally
{
_waitingOnFreeThreadCounter.Decrement();
}
}
}
//block if the scheduler is full
try
{
_waitingOnFreeThreadCounter.Increment();
taskFactory.Scheduler.WaitForFreeThread.Wait(workGroup);
}
finally
{
_waitingOnFreeThreadCounter.Decrement();
}
}
}
