public PersistentMessage Dequeue(string subqueue)
{
Api.JetSetCurrentIndex(session, msgs, "by_sub_queue");
Api.MakeKey(session, msgs, subqueue, Encoding.Unicode, MakeKeyGrbit.NewKey);
if (Api.TrySeek(session, msgs, SeekGrbit.SeekGE) == false)
return null;
Api.MakeKey(session, msgs, subqueue, Encoding.Unicode, MakeKeyGrbit.NewKey | MakeKeyGrbit.FullColumnEndLimit);
try
{
Api.JetSetIndexRange(session, msgs, SetIndexRangeGrbit.RangeInclusive | SetIndexRangeGrbit.RangeUpperLimit);
}
catch (EsentErrorException e)
{
if (e.Error != JET_err.NoCurrentRecord)
throw;
return null;
}
do
{
var id = new MessageId
{
MessageIdentifier = new Guid(Api.RetrieveColumn(session, msgs, msgsColumns["msg_id"])),
SourceInstanceId = new Guid(Api.RetrieveColumn(session, msgs, msgsColumns["instance_id"]))
};
var status = (MessageStatus)Api.RetrieveColumnAsInt32(session, msgs, msgsColumns["status"]).Value;
logger.DebugFormat("Scanning incoming message {2} on '{0}/{1}' with status {3}",
queueName, subqueue, id, status);
if (status != MessageStatus.ReadyToDeliver)
continue;
try
{
using (var update = new Update(session, msgs, JET_prep.Replace))
{
Api.SetColumn(session, msgs, msgsColumns["status"], (int)MessageStatus.Processing);
update.Save();
}
}
catch (EsentErrorException e)
{
logger.DebugFormat("Write conflict on '{0}/{1}' for {2}, skipping message",
queueName, subqueue, id);
if (e.Error == JET_err.WriteConflict)
continue;
throw;
}
var bookmark = new MessageBookmark { QueueName = queueName };
Api.JetGetBookmark(session, msgs, bookmark.Bookmark, bookmark.Size, out bookmark.Size);
changeNumberOfMessages(-1);
logger.DebugFormat("Dequeuing message {2} from '{0}/{1}'",
queueName, subqueue, id);
var headersAsQueryString = Api.RetrieveColumnAsString(session, msgs, msgsColumns["headers"]);
var message = new PersistentMessage
{
Bookmark = bookmark,
Headers = HttpUtility.ParseQueryString(headersAsQueryString),
Queue = queueName,
SentAt = DateTime.FromOADate(Api.RetrieveColumnAsDouble(session, msgs, msgsColumns["timestamp"]).Value),
Data = Api.RetrieveColumn(session, msgs, msgsColumns["data"]),
Id = id,
SubQueue = subqueue,
Status = (MessageStatus)Api.RetrieveColumnAsInt32(session, msgs, msgsColumns["status"]).Value
};
return message;
} while (Api.TryMoveNext(session, msgs));
return null;
}
public void EnqueueDirectlyTo(string queue, string subqueue, MessagePayload payload)
{
EnsureEnslistment();
var message = new PersistentMessage
{
Data = payload.Data,
Headers = payload.Headers,
Id = new MessageId
{
SourceInstanceId = queueStorage.Id,
MessageIdentifier = GuidCombGenerator.Generate()
},
Queue = queue,
SentAt = DateTime.Now,
SubQueue = subqueue,
Status = MessageStatus.EnqueueWait
};
queueStorage.Global(actions =>
{
var queueActions = actions.GetQueue(queue);
var bookmark = queueActions.Enqueue(message);
actions.RegisterUpdateToReverse(Enlistment.Id, bookmark, MessageStatus.EnqueueWait, subqueue);
actions.Commit();
});
OnMessageQueuedForReceive(message);
lock (newMessageArrivedLock)
{
Monitor.PulseAll(newMessageArrivedLock);
}
}
public MessageBookmark MoveTo(string subQueue, PersistentMessage message)
{
Api.JetGotoBookmark(session, msgs, message.Bookmark.Bookmark, message.Bookmark.Size);
var id = new MessageId
{
MessageIdentifier = new Guid(Api.RetrieveColumn(session, msgs, msgsColumns["msg_id"])),
SourceInstanceId = new Guid(Api.RetrieveColumn(session, msgs, msgsColumns["instance_id"]))
};
using (var update = new Update(session, msgs, JET_prep.Replace))
{
Api.SetColumn(session, msgs, msgsColumns["status"], (int)MessageStatus.SubqueueChanged);
Api.SetColumn(session, msgs, msgsColumns["subqueue"], subQueue, Encoding.Unicode);
var bookmark = new MessageBookmark { QueueName = queueName };
update.Save(bookmark.Bookmark, bookmark.Size, out bookmark.Size);
logger.DebugFormat("Moving message {0} to subqueue {1}",
id, queueName);
return bookmark;
}
}
