Esempio n. 1
0
        protected override void PerformWork(ref List <ArraySegment <Message> > items, out string nextCursor, ref int totalCount, out object state)
        {
            var cursors = new List <Cursor>();

            lock (_lockObj)
            {
                items = new List <ArraySegment <Message> >(_cursors.Count);
                for (int i = 0; i < _cursors.Count; i++)
                {
                    Cursor cursor = Cursor.Clone(_cursors[i]);
                    cursors.Add(cursor);

                    MessageStoreResult <Message> storeResult = _cursorTopics[i].Store.GetMessages(cursor.Id, MaxMessages);
                    ulong next = storeResult.FirstMessageId + (ulong)storeResult.Messages.Count;

                    cursor.Id = next;

                    if (storeResult.Messages.Count > 0)
                    {
                        items.Add(storeResult.Messages);
                        totalCount += storeResult.Messages.Count;
                    }
                }

                nextCursor = Cursor.MakeCursor(cursors);

                // Return the state as a list of cursors
                state = cursors;
            }
        }
Esempio n. 2
0
 public override string GetCursor()
 {
     return(Cursor.MakeCursor(_cursors));
 }
Esempio n. 3
0
        protected override void PerformWork(ref List <ArraySegment <Message> > items, out string nextCursor, ref int totalCount, out object state)
        {
            // The list of cursors represent (streamid, payloadid)
            var cursors = new List <Cursor>();

            foreach (var stream in _streams)
            {
                // Get the mapping for this stream
                Linktionary <ulong, ScaleoutMapping> mapping = stream.Value;

                // See if we have a cursor for this key
                Cursor cursor = null;

                // REVIEW: We should optimize this
                int index = _cursors.FindIndex(c => c.Key == stream.Key);

                bool consumed = true;

                if (index != -1)
                {
                    cursor = Cursor.Clone(_cursors[index]);

                    // If there's no node for this cursor id it's likely because we've
                    // had an app domain restart and the cursor position is now invalid.
                    if (mapping[cursor.Id] == null)
                    {
                        // Set it to the first id in this mapping
                        cursor.Id = stream.Value.MinKey;

                        // Mark this cursor as unconsumed
                        consumed = false;
                    }
                }
                else
                {
                    // Create a cursor and add it to the list.
                    // Point the Id to the first value
                    cursor = new Cursor(key: stream.Key, id: stream.Value.MinKey);

                    consumed = false;
                }

                cursors.Add(cursor);

                // Try to find a local mapping for this payload
                LinkedListNode <KeyValuePair <ulong, ScaleoutMapping> > node = mapping[cursor.Id];

                // Skip this node only if this isn't a new cursor
                if (node != null && consumed)
                {
                    // Skip this node since we've already consumed it
                    node = node.Next;
                }

                while (node != null)
                {
                    KeyValuePair <ulong, ScaleoutMapping> pair = node.Value;

                    // Stop if we got more than max messages
                    if (totalCount >= MaxMessages)
                    {
                        break;
                    }

                    // It should be ok to lock here since groups aren't modified that often
                    lock (EventKeys)
                    {
                        // For each of the event keys we care about, extract all of the messages
                        // from the payload
                        foreach (var eventKey in EventKeys)
                        {
                            LocalEventKeyInfo info;
                            if (pair.Value.EventKeyMappings.TryGetValue(eventKey, out info))
                            {
                                int maxMessages = Math.Min(info.Count, MaxMessages);
                                MessageStoreResult <Message> storeResult = info.Store.GetMessages(info.MinLocal, maxMessages);

                                if (storeResult.Messages.Count > 0)
                                {
                                    items.Add(storeResult.Messages);
                                    totalCount += storeResult.Messages.Count;
                                }
                            }
                        }
                    }

                    // Update the cursor id
                    cursor.Id = pair.Key;
                    node      = node.Next;
                }
            }

            nextCursor = Cursor.MakeCursor(cursors);

            state = cursors;
        }