public JsonRpcServerBase(INodeAPI node, INodeTransactionAPI trans)
        {
            _node  = node;
            _trans = trans;

            if (_queue == null && NodeService.Dag != null)
            {
                _queue     = new ConcurrentQueue <TxInfoBase>();
                _haveBlock = new EventWaitHandle(false, EventResetMode.ManualReset);
                _instances = new ConcurrentDictionary <int, JsonRpcServerBase>();

                NodeService.Dag.OnNewBlock += NewBlockMonitor;

                _ = Task.Run(async() => {
                    while (true)
                    {
                        await _haveBlock.AsTaskAsync();
                        _haveBlock.Reset();

                        TxInfoBase info;
                        while (_queue.TryDequeue(out info))
                        {
                            foreach (var inst in _instances.Values)
                            {
                                try
                                {
                                    if (inst.GetIfInterested(info.to))
                                    {
                                        inst.Notify?.Invoke(this, new News {
                                            catalog = info.GetType().Name, content = info
                                        });
                                    }
                                }
                                catch
                                {
                                }
                            }
                        }
                    }
                }).ConfigureAwait(false);
            }

            _instances?.TryAdd(this.GetHashCode(), this);
        }