/// <summary>
/// Constructor for ServiceLock processor.
/// </summary>
/// <param name="numberThreads">The number of threads allocated to the processor.</param>
/// <param name="terminationEvent">Stop signal</param>
public ServiceLockProcessor(int numberThreads, ManualResetEvent terminationEvent)
{
_terminationEvent = terminationEvent;
_threadStop = new ManualResetEvent(false);
_threadPool = new ServiceLockThreadPool(numberThreads);
_threadPool.ThreadPoolName = "ServiceLock Pool";
ServiceLockFactoryExtensionPoint ep = new ServiceLockFactoryExtensionPoint();
object[] factories = ep.CreateExtensions();
if (factories == null || factories.Length == 0)
{
// No extension for the ServiceLock processor.
Platform.Log(LogLevel.Warn, "No ServiceLockFactory Extension found.");
}
else
{
foreach (object obj in factories)
{
IServiceLockProcessorFactory factory = obj as IServiceLockProcessorFactory;
if (factory != null)
{
ServiceLockTypeEnum type = factory.GetServiceLockType();
_extensions.Add(type, factory);
}
else
{
Platform.Log(LogLevel.Error, "Unexpected incorrect type loaded for extension: {0}",
obj.GetType());
}
}
}
}
/// <summary>
/// The processing thread.
/// </summary>
/// <remarks>
/// This method queries the database for ServiceLock entries to work on, and then uses
/// a thread pool to process the entries.
/// </remarks>
public void Run()
{
// Start the thread pool
if (!_threadPool.Active)
{
_threadPool.Start();
}
// Reset any queue items related to this service that are have the Lock bit set.
try
{
ResetLocked();
}
catch (Exception e)
{
Platform.Log(LogLevel.Fatal, e,
"Unable to reset ServiceLock items on startup. There may be ServiceLock items orphaned in the queue.");
}
Platform.Log(LogLevel.Info, "ServiceLock Processor is running");
while (true)
{
try
{
if (_threadPool.CanQueueItem)
{
Model.ServiceLock queueListItem;
using (IUpdateContext updateContext = _store.OpenUpdateContext(UpdateContextSyncMode.Flush))
{
IQueryServiceLock select = updateContext.GetBroker <IQueryServiceLock>();
ServiceLockQueryParameters parms = new ServiceLockQueryParameters();
parms.ProcessorId = ServerPlatform.ProcessorId;
queueListItem = select.FindOne(parms);
updateContext.Commit();
}
if (queueListItem == null)
{
WaitHandle.WaitAny(new WaitHandle[] { _terminationEvent, _threadStop }, TimeSpan.FromSeconds(30), false);
_threadStop.Reset();
}
else
{
if (!_extensions.ContainsKey(queueListItem.ServiceLockTypeEnum))
{
Platform.Log(LogLevel.Error,
"No extensions loaded for ServiceLockTypeEnum item type: {0}. Failing item.",
queueListItem.ServiceLockTypeEnum);
//Just fail the ServiceLock item, not much else we can do
ResetServiceLock(queueListItem);
continue;
}
IServiceLockProcessorFactory factory = _extensions[queueListItem.ServiceLockTypeEnum];
IServiceLockItemProcessor processor;
try
{
processor = factory.GetItemProcessor();
}
catch (Exception e)
{
Platform.Log(LogLevel.Error, e, "Unexpected exception creating ServiceLock processor.");
ResetServiceLock(queueListItem);
continue;
}
_threadPool.Enqueue(processor, queueListItem, delegate(IServiceLockItemProcessor queueProcessor, Model.ServiceLock queueItem)
{
try
{
queueProcessor.Process(queueItem);
}
catch (Exception e)
{
Platform.Log(LogLevel.Error, e,
"Unexpected exception when processing ServiceLock item of type {0}. Failing Queue item. (GUID: {1})",
queueItem.ServiceLockTypeEnum,
queueItem.GetKey());
ServerPlatform.Alert(AlertCategory.Application, AlertLevel.Error, "ServiceLockProcessor",
AlertTypeCodes.UnableToProcess,
null, TimeSpan.Zero,
"Exception thrown when processing {0} ServiceLock item : {1}",
queueItem.ServiceLockTypeEnum.Description, e.Message);
ResetServiceLock(queueItem);
}
// Cleanup the processor
queueProcessor.Dispose();
// Signal the thread to come out of sleep mode
_threadStop.Set();
});
}
}
else
{
// Wait for only 5 seconds when the thread pool is all in use.
WaitHandle.WaitAny(new WaitHandle[] { _terminationEvent, _threadStop }, TimeSpan.FromSeconds(5), false);
_threadStop.Reset();
}
}
catch (Exception ex)
{
Platform.Log(LogLevel.Error, ex, "Exception has occurred : {0}. Retry later.", ex.Message);
WaitHandle.WaitAny(new WaitHandle[] { _terminationEvent, _threadStop }, TimeSpan.FromSeconds(5), false);
_threadStop.Reset();
}
if (_stop)
{
return;
}
}
}
