/// <summary>
/// Drain all the dequeuers.
/// Would be called during ChangeRole (to S, None), Abort, Close.
/// </summary>
/// <param name="cause">The DrainCause</param>
private void DrainDequeuers(DequeuerState cause)
{
TaskCompletionSource <ConditionalValue <IListElement <T> > > tcs;
Exception exc = null;
switch (cause)
{
case DequeuerState.Aborting:
case DequeuerState.Closing:
exc = new FabricObjectClosedException(string.Format("Dequeue was canceled as the queue is {0}. Please dispose the current transaction and retry the operation with a new transaction.", cause));
break;
case DequeuerState.ChangeRoleFromPrimary:
exc = new FabricNotPrimaryException("Dequeue was canceled as the role is no longer primary. Please dispose the current transaction and retry the operation with a new transaction.");
break;
default:
TestableAssertHelper.FailInvalidData(
this.traceType,
"DataStore.DrainDequeuers",
"DequeueScheduler.DrainDequeuers : Invalid DrainQueue cause : {0}",
cause);
break; // unreachable
}
lock (this.updateLatch)
{
this.dequeuersState = cause;
}
while (this.dequeuerQueue.TryDequeue(out tcs))
{
tcs.TrySetException(exc);
}
}
public void ChangeRole(ReplicaRole currentRole, ReplicaRole newRole)
{
// noop the call for a NonBlocking Queue
if (this.queueMode == RCQMode.Blocking)
{
if (currentRole == ReplicaRole.Primary)
{
this.DrainDequeuers(DequeuerState.ChangeRoleFromPrimary);
}
if (newRole == ReplicaRole.Primary)
{
this.AssertNoDequeuer();
this.dequeuersState = DequeuerState.OnPrimary;
}
}
}
public DataStore(List <IListElement <T> > listElements, RCQMode rcqMode, string traceType)
{
this.queueMode = rcqMode;
this.traceType = traceType;
this.dequeuerQueue = new ConcurrentQueue <TaskCompletionSource <ConditionalValue <IListElement <T> > > >();
this.dequeuersState = DequeuerState.None;
this.LinkedCount = 0;
this.updateLatch = new object();
this.ListElements = new ConcurrentDictionary <long, ListElement>();
this.head = null;
this.tail = null;
// descending order
listElements.Sort((a, b) => b.Id.CompareTo(a.Id));
foreach (var listElement in listElements)
{
this.AddListElement(listElement);
this.AssertUnlinked(listElement);
this.LinkHeadUnsafe(listElement);
}
}
