public Worker NextAvailableWorker()
{
try
{
Message availableWorker;
if (!storageLock.TryEnterReadLock(MaxTimeToWaitForAvailableWorker))
{
return(null);
}
try
{
if (unitOfWork.HasActiveTransaction())
{
availableWorker = storageQueue.Receive(MaxTimeToWaitForAvailableWorker, unitOfWork.Transaction);
}
else
{
availableWorker = storageQueue.Receive(MaxTimeToWaitForAvailableWorker, MessageQueueTransactionType.Automatic);
}
}
finally
{
storageLock.ExitReadLock();
}
if (availableWorker == null)
{
return(null);
}
var address = MsmqUtilities.GetIndependentAddressForQueue(availableWorker.ResponseQueue);
string registeredWorkerSessionId;
var sessionId = availableWorker.Label;
if (String.IsNullOrEmpty(sessionId)) //Old worker
{
Logger.InfoFormat("Using an old version Worker at '{0}'.", address);
return(new Worker(address, sessionId));
}
if (!registeredWorkerAddresses.TryGetValue(address, out registeredWorkerSessionId))
{
// Distributor could have been restarted, hence the reason we do not have the worker registered.
registeredWorkerAddresses[address] = sessionId;
Logger.InfoFormat("Worker at '{0}' has been re-registered with distributor.", address);
}
return(new Worker(address, sessionId));
}
catch (MessageQueueException e)
{
Logger.InfoFormat("NextAvailableWorker Exception", e);
return(null);
}
}
