protected override BlittableJsonReaderObject GetUpdatedValue(long index, RawDatabaseRecord record, JsonOperationContext context, BlittableJsonReaderObject existingValue)
        {
            var itemId = GetItemId();

            if (existingValue == null)
            {
                throw new SubscriptionDoesNotExistException($"Subscription with id '{itemId}' does not exist");
            }

            var subscription = JsonDeserializationCluster.SubscriptionState(existingValue);

            var topology            = record.Topology;
            var lastResponsibleNode = AcknowledgeSubscriptionBatchCommand.GetLastResponsibleNode(HasHighlyAvailableTasks, topology, NodeTag);
            var appropriateNode     = topology.WhoseTaskIsIt(RachisState.Follower, subscription, lastResponsibleNode);

            if (appropriateNode == null && record.DeletionInProgress.ContainsKey(NodeTag))
            {
                throw new DatabaseDoesNotExistException(
                          $"Stopping subscription '{SubscriptionName}' on node {NodeTag}, because database '{DatabaseName}' is being deleted.");
            }

            if (appropriateNode != NodeTag)
            {
                throw new SubscriptionDoesNotBelongToNodeException(
                          $"Can't update subscription with name {itemId} by node {NodeTag}, because it's not its task to update this subscription");
            }

            subscription.LastClientConnectionTime = LastClientConnectionTime;
            subscription.NodeTag = NodeTag;

            return(context.ReadObject(subscription.ToJson(), itemId));
        }
        protected override BlittableJsonReaderObject GetUpdatedValue(long index, DatabaseRecord record, JsonOperationContext context, BlittableJsonReaderObject existingValue, RachisState state)
        {
            var itemId = GetItemId();

            if (existingValue == null)
            {
                throw new RachisApplyException($"Subscription with id {itemId} does not exist");
            }

            var subscription = JsonDeserializationCluster.SubscriptionState(existingValue);

            var lastResponsibleNode = AcknowledgeSubscriptionBatchCommand.GetLastResponsibleNode(HasHighlyAvailableTasks, record.Topology, NodeTag);

            if (record.Topology.WhoseTaskIsIt(state, subscription, lastResponsibleNode) != NodeTag)
            {
                throw new RachisApplyException($"Can't update subscription with name {itemId} by node {NodeTag}, because it's not it's task to update this subscription");
            }

            subscription.LastClientConnectionTime = LastClientConnectionTime;
            subscription.NodeTag = NodeTag;

            return(context.ReadObject(subscription.ToJson(), itemId));
        }
        public override unsafe void Execute(ClusterOperationContext context, Table items, long index, RawDatabaseRecord record, RachisState state, out object result)
        {
            result = null;
            var shouldUpdateChangeVector = true;
            var subscriptionName         = SubscriptionName;

            if (string.IsNullOrEmpty(subscriptionName))
            {
                subscriptionName = SubscriptionId.ToString();
            }

            //insert all docs to voron table. If exists, then batchId will be replaced
            var subscriptionStateTable = context.Transaction.InnerTransaction.OpenTable(ClusterStateMachine.SubscriptionStateSchema, ClusterStateMachine.SubscriptionState);

            var itemKey = SubscriptionState.GenerateSubscriptionItemKeyName(DatabaseName, subscriptionName);

            using (Slice.From(context.Allocator, itemKey.ToLowerInvariant(), out Slice valueNameLowered))
                using (Slice.From(context.Allocator, itemKey, out Slice valueName))
                {
                    if (items.ReadByKey(valueNameLowered, out var tvr) == false)
                    {
                        throw new RachisApplyException($"Cannot find subscription {subscriptionName} @ {DatabaseName}");
                    }

                    var ptr           = tvr.Read(2, out int size);
                    var existingValue = new BlittableJsonReaderObject(ptr, size, context);

                    if (existingValue == null)
                    {
                        throw new SubscriptionDoesNotExistException($"Subscription with name '{subscriptionName}' does not exist in database '{DatabaseName}'");
                    }

                    var subscriptionState = JsonDeserializationClient.SubscriptionState(existingValue);

                    var topology            = record.Topology;
                    var lastResponsibleNode = AcknowledgeSubscriptionBatchCommand.GetLastResponsibleNode(HasHighlyAvailableTasks, topology, NodeTag);
                    var appropriateNode     = topology.WhoseTaskIsIt(RachisState.Follower, subscriptionState, lastResponsibleNode);
                    if (appropriateNode == null && record.DeletionInProgress.ContainsKey(NodeTag))
                    {
                        throw new DatabaseDoesNotExistException($"Stopping subscription '{subscriptionName}' on node {NodeTag}, because database '{DatabaseName}' is being deleted.");
                    }

                    if (appropriateNode != NodeTag)
                    {
                        throw new SubscriptionDoesNotBelongToNodeException(
                                  $"Cannot apply {nameof(AcknowledgeSubscriptionBatchCommand)} for subscription '{subscriptionName}' with id '{SubscriptionId}', on database '{DatabaseName}', on node '{NodeTag}'," +
                                  $" because the subscription task belongs to '{appropriateNode ?? "N/A"}'.")
                              {
                                  AppropriateNode = appropriateNode
                              };
                    }

                    if (CurrentChangeVector == nameof(Constants.Documents.SubscriptionChangeVectorSpecialStates.DoNotChange))
                    {
                        context.ReadObject(existingValue, subscriptionName);
                        shouldUpdateChangeVector = false;
                    }

                    if (subscriptionState.ChangeVectorForNextBatchStartingPoint != PreviouslyRecordedChangeVector)
                    {
                        throw new SubscriptionChangeVectorUpdateConcurrencyException($"Can't record subscription with name '{subscriptionName}' due to inconsistency in change vector progress. Probably there was an admin intervention that changed the change vector value. Stored value: {subscriptionState.ChangeVectorForNextBatchStartingPoint}, received value: {PreviouslyRecordedChangeVector}");
                    }

                    if (shouldUpdateChangeVector)
                    {
                        subscriptionState.ChangeVectorForNextBatchStartingPoint =
                            ChangeVectorUtils.MergeVectors(CurrentChangeVector, subscriptionState.ChangeVectorForNextBatchStartingPoint);
                        subscriptionState.NodeTag = NodeTag;
                        using (var obj = context.ReadObject(subscriptionState.ToJson(), "subscription"))
                        {
                            ClusterStateMachine.UpdateValue(index, items, valueNameLowered, valueName, obj);
                        }
                    }
                }

            foreach (var deletedId in Deleted)
            {
                using (SubscriptionConnectionsState.GetDatabaseAndSubscriptionAndDocumentKey(context, DatabaseName, SubscriptionId, deletedId, out var key))
                {
                    using var _ = Slice.External(context.Allocator, key, out var keySlice);
                    subscriptionStateTable.DeleteByKey(keySlice);
                }
            }

            foreach (var documentRecord in Documents)
            {
                using (SubscriptionConnectionsState.GetDatabaseAndSubscriptionAndDocumentKey(context, DatabaseName, SubscriptionId, documentRecord.DocumentId, out var key))
                    using (subscriptionStateTable.Allocate(out var tvb))
                    {
                        using var _  = Slice.External(context.Allocator, key, out var keySlice);
                        using var __ = Slice.From(context.Allocator, documentRecord.ChangeVector, out var changeVectorSlice);

                        tvb.Add(keySlice);
                        tvb.Add(changeVectorSlice);
                        tvb.Add(Bits.SwapBytes(index)); // batch id

                        subscriptionStateTable.Set(tvb);
                    }
            }
            foreach (var revisionRecord in Revisions)
            {
                using (SubscriptionConnectionsState.GetDatabaseAndSubscriptionAndRevisionKey(context, DatabaseName, SubscriptionId, revisionRecord.Current, out var key))
                    using (subscriptionStateTable.Allocate(out var tvb))
                    {
                        using var _  = Slice.External(context.Allocator, key, out var keySlice);
                        using var __ = Slice.From(context.Allocator, revisionRecord.Previous ?? string.Empty, out var changeVectorSlice);

                        tvb.Add(keySlice);
                        tvb.Add(changeVectorSlice);     //prev change vector
                        tvb.Add(Bits.SwapBytes(index)); // batch id

                        subscriptionStateTable.Set(tvb);
                    }
            }
        }