Exemple #1
0
        /// <summary>
        /// 三经典模式:推拉模式(管道模式)
        /// 一个消息只能被消费一次
        /// </summary>
        static void PushPull()
        {
            using (var pullSocket = new PullSocket())
                using (var pushSocket = new PushSocket())
                {
                    var port = pullSocket.BindRandomPort($"{address}");
                    pushSocket.Connect($"{address}:" + port);

                    pushSocket.SendMoreFrame("hello").SendFrame("hello world");
                    var s = pullSocket.ReceiveFrameString();
                    s += pullSocket.ReceiveFrameString();
                    Console.WriteLine(s);//hellohello world
                }
        }
Exemple #2
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        public static void Main(string[] args)
        {
            using (var client = new PullSocket())
            {
                client.Bind("tcp://127.0.0.1:5488");
                while (true)
                {
                    string a = client.ReceiveFrameString();  // To receive a flag from external programs to start the service
                    if (bool.Parse(a))
                    {
                        Console.WriteLine("START");

                        // Added Begin
                        CancellationTokenSource source = new CancellationTokenSource();
                        CancellationToken       token  = source.Token;
                        // Added End

                        Thread t = new Thread(new ParameterizedThreadStart(ThreadProc));

                        //t.Start(args);
                        t.Start(source);

                        //CreateHostBuilder(args).Build().RunAsync(token).Wait();   // This works at the first start
                        // ATTENTION! CreateHostBuilder(args).Build().Run() will return an error about args.Length < 0
                        CreateHostBuilder(args).Build().RunAsync(token);

                        Console.WriteLine("DONE Start");
                    }
                }
            }
        }
 public static void Main(string[] args)
 {
     // Task Worker
     // Connects PULL socket to tcp://localhost:5557
     // collects workload for socket from Ventilator via that socket
     // Connects PUSH socket to tcp://localhost:5558
     // Sends results to Sink via that socket
     Console.WriteLine("====== WORKER ======");
     using (var receiver = new PullSocket(">tcp://127.0.0.1:5557"))
         using (var sender = new PushSocket(">tcp://127.0.0.1:5558"))
         {
             //process tasks forever
             while (true)
             {
                 //workload from the vetilator is a simple delay
                 //to simulate some work being done, see
                 //Ventilator.csproj Proram.cs for the workload sent
                 //In real life some more meaningful work would be done
                 string workload = receiver.ReceiveFrameString();
                 //simulate some work being done
                 Thread.Sleep(int.Parse(workload));
                 //send results to sink, sink just needs to know worker
                 //is done, message content is not important, just the presence of
                 //a message means worker is done.
                 //See Sink.csproj Proram.cs
                 Console.WriteLine("Sending to Sink");
                 sender.SendFrame(string.Empty);
             }
         }
 }
Exemple #4
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        static void Main(string[] args)
        {
            Console.WriteLine("====== WORKER ======");

            var sinkPort       = ConfigurationManager.AppSettings.Get("sinkPort") ?? "8088";
            var ventilatorPort = ConfigurationManager.AppSettings.Get("ventilatorPort") ?? "400";

            using (var receiver = new PullSocket($">tcp://localhost:{sinkPort}"))
                using (var sender = new PushSocket($">tcp://localhost:{ventilatorPort}"))
                {
                    while (true)
                    {
                        string workload = receiver.ReceiveFrameString();

                        // the protocoll is as follows: [0] -> lower, [1] -> upper,  [2] -> height
                        string[] workLoadArray = workload.Split(',');

                        var calculator = new MandelbrotCalculator();
                        var result     = calculator.Calculate(Convert.ToInt32(workLoadArray[2]), 400, Convert.ToInt32(workLoadArray[0]), Convert.ToInt32(workLoadArray[1]));

                        byte[]          data;
                        BinaryFormatter binaryFormatter = new BinaryFormatter();

                        using (var memoryStream = new MemoryStream())
                        {
                            binaryFormatter.Serialize(memoryStream, result);
                            data = memoryStream.ToArray();
                        }

                        Console.WriteLine("Sending");
                        sender.SendFrame(data);
                    }
                }
        }
Exemple #5
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        private bool _disposedValue = false; // Для определения избыточных вызовов

        #endregion Fields

        #region Constructors

        public FanBrocker(NetMQContext context, string ventAddress, string sinkAddress, int workersCnt)
        {
            _logger.Trace("Brocker created");
            _ventAddress = ventAddress;
            _sinkAddress = sinkAddress;

            _sinkSocket = context.CreatePullSocket();
            _sinkSocket.Options.ReceiveBuffer = 1;

            _sinkSocket.Bind(sinkAddress);

            _ventSocket = context.CreatePushSocket();
            _ventSocket.Options.SendBuffer = 1;
            _ventSocket.Bind(ventAddress);

            Task.Run(() =>
            {
                try
                {
                    while (true)
                    {
                        var ba = _sinkSocket.ReceiveFrameString();
                        _logger.Trace("Brocker received data {0}", ba);
                        var data = JsonConvert.DeserializeObject<ProcessedEventArgs>(ba);
                        OnFramesProcessed(data);
                    }
                }
                catch (Exception)
                {

                    _logger.Error("EXCEPTION");
                }

            });
        }
        static void Main(string[] args)
        {
            Console.WriteLine("====== Back Queue STARTED ======");
            using var fromWorkerForPosion = new PullSocket($"@{ThreadSafeFactory.BackPosionQueue}");
            using var fromWorkerForUrl    = new PullSocket($"@{ThreadSafeFactory.BackUrlQueue}");
            using var forFrontForUrl      = new PushSocket($"@{ThreadSafeFactory.BackQueue}");
            Console.WriteLine("Socket initialized");

            var fromWorkerProcessorForFrontQueue = Task.Run(() =>
            {
                do
                {
                    try
                    {
                        Console.WriteLine($"Waiting for worker link");
                        var queueItem = fromWorkerForUrl.ReceiveFrameString();
                        Console.WriteLine($"Received [{queueItem}] from worker");
                        Console.WriteLine($"Sending to front queue");
                        forFrontForUrl.SendFrame(queueItem);
                        Console.WriteLine($"Sent to front queue");
                    }
                    catch (Exception ex)
                    {
                        Console.WriteLine($"Error in Front Queue Processor {ex.Message}");
                    }
                } while (true);
            });
            var fromWorkerProcessorForPoison = Task.Run(() =>
            {
                do
                {
                    Console.WriteLine($"Waiting for poison items");
                    var workload = fromWorkerForPosion.ReceiveFrameString();
                    UrlPosionQueueItem queueItem = workload.FromJson <UrlPosionQueueItem>();
                    _posionQueue.Enqueue(queueItem);
                    Console.WriteLine($"Received poison [{queueItem.ToJson()}] from worker");
                } while (true);
            });

            var poisonQueueProcessor = Task.Run(() =>
            {
                do
                {
                    //while (_posionQueue.IsEmpty)
                    //{
                    //    Task.Delay(5000).Wait();
                    //}
                    if (_posionQueue.TryDequeue(out UrlPosionQueueItem queueItem))
                    {
                        Console.WriteLine($"Processing poison {queueItem.ToJson()}");
                    }
                    // TODO: Persist all posion queue items with failure reasons in db
                } while (true);
            });

            Task.WaitAll(fromWorkerProcessorForFrontQueue, /* fromWorkerProcessorForPoison,*/ poisonQueueProcessor);
            Console.WriteLine("====== FRONT QUEUE ======");
        }
Exemple #7
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        public void SeparateControlSocketsObservedMessages()
        {
            using (var front = new RouterSocket())
                using (var back = new DealerSocket())
                    using (var controlInPush = new PushSocket())
                        using (var controlInPull = new PullSocket())
                            using (var controlOutPush = new PushSocket())
                                using (var controlOutPull = new PullSocket())
                                {
                                    front.Bind("inproc://frontend");
                                    back.Bind("inproc://backend");

                                    controlInPush.Bind("inproc://controlIn");
                                    controlInPull.Connect("inproc://controlIn");
                                    controlOutPush.Bind("inproc://controlOut");
                                    controlOutPull.Connect("inproc://controlOut");

                                    var proxy = new Proxy(front, back, controlInPush, controlOutPush);
                                    Task.Factory.StartNew(proxy.Start);

                                    using (var client = new RequestSocket())
                                        using (var server = new ResponseSocket())
                                        {
                                            client.Connect("inproc://frontend");
                                            server.Connect("inproc://backend");

                                            client.SendFrame("hello");
                                            Assert.AreEqual("hello", server.ReceiveFrameString());
                                            server.SendFrame("reply");
                                            Assert.AreEqual("reply", client.ReceiveFrameString());
                                        }

                                    Assert.IsNotNull(controlInPull.ReceiveFrameBytes()); // receive identity
                                    Assert.IsEmpty(controlInPull.ReceiveFrameString());  // pull terminator
                                    Assert.AreEqual("hello", controlInPull.ReceiveFrameString());

                                    Assert.IsNotNull(controlOutPull.ReceiveFrameBytes()); // receive identity
                                    Assert.IsEmpty(controlOutPull.ReceiveFrameString());  // pull terminator
                                    Assert.AreEqual("reply", controlOutPull.ReceiveFrameString());

                                    proxy.Stop();
                                }
        }
        public void SimplePushPull()
        {
            using (var pullSocket = new PullSocket())
                using (var pushSocket = new PushSocket())
                {
                    var port = pullSocket.BindRandomPort("tcp://127.0.0.1");
                    pushSocket.Connect("tcp://127.0.0.1:" + port);

                    pushSocket.SendFrame("hello");

                    Assert.AreEqual("hello", pullSocket.ReceiveFrameString());
                }
        }
        public void EmptyMessage()
        {
            using (var pullSocket = new PullSocket())
                using (var pushSocket = new PushSocket())
                {
                    var port = pullSocket.BindRandomPort("tcp://127.0.0.1");
                    pushSocket.Connect("tcp://127.0.0.1:" + port);

                    pushSocket.SendFrame(new byte[300]);

                    Assert.AreEqual(300, pullSocket.ReceiveFrameString().Length);
                }
        }
            public void It_Should_Send_Message_To_Socket()
            {
                const string address = "tcp://127.0.0.1:12345";

                using (var socket = new PullSocket())
                    using (AutoMock mock = AutoMock.GetLoose())
                    {
                        mock.Provide <IOptions <MessageClientOptions> >(new OptionsWrapper <MessageClientOptions>(new MessageClientOptions
                        {
                            Address = address
                        }));

                        socket.Connect(address);

                        var service = mock.Create <MessageClientImpl>();
                        service.ScheduleDelivery("A some message 1");
                        service.ScheduleDelivery("A some message 2");
                        service.ScheduleDelivery("A some message 3");

                        Assert.Equal("A some message 1", socket.ReceiveFrameString());
                        Assert.Equal("A some message 2", socket.ReceiveFrameString());
                        Assert.Equal("A some message 3", socket.ReceiveFrameString());
                    }
            }
Exemple #11
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        static void Main(string[] args)
        {
            // Task Sink
            // Bindd PULL socket to tcp://localhost:5558
            // Collects results from workers via that socket
            Console.WriteLine("====== SINK ======");

            //socket to receive messages on
            using (var receiver = new PullSocket("@tcp://localhost:5558"))
            {
                //wait for start of batch (see Ventilator.csproj Program.cs)
                var startOfBatchTrigger = receiver.ReceiveFrameString();
                Console.WriteLine("Seen start of batch");

                //Start our clock now
                var watch = Stopwatch.StartNew();

                for (int taskNumber = 0; taskNumber < 100; taskNumber++)
                {
                    var workerDoneTrigger = receiver.ReceiveFrameString();
                    if (taskNumber % 10 == 0)
                    {
                        Console.Write(":");
                    }
                    else
                    {
                        Console.Write(".");
                    }
                }
                watch.Stop();
                //Calculate and report duration of batch
                Console.WriteLine();
                Console.WriteLine("Total elapsed time {0} msec", watch.ElapsedMilliseconds);
                Console.ReadLine();
            }
        }
Exemple #12
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 public override IObservable <string> Generate()
 {
     return(Observable.Create <string>((observer, cancellationToken) =>
     {
         return Task.Factory.StartNew(() =>
         {
             using (var receiver = new PullSocket(string.Format("@tcp://{0}:{1}", Address, Port)))
             {
                 observer.OnNext(receiver.ReceiveFrameString());
                 while (!cancellationToken.IsCancellationRequested)
                 {
                     string msg = receiver.ReceiveFrameString();
                     if (msg != null)
                     {
                         observer.OnNext(msg);
                         Console.WriteLine("From Client: {0}", msg);
                     }
                 }
             }
         });
     })
            .PublishReconnectable()
            .RefCount());
 }
Exemple #13
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        static void Main(string[] args)
        {
            // Task Worker
            // Connects PULL socket to tcp://localhost:5557
            // collects workload for socket from Ventilator via that socket
            // Connects PUSH socket to tcp://localhost:5558
            // Sends results to Sink via that socket
            Console.WriteLine("====== WORKER ======");

            var mainServer = ConfigurationManager.AppSettings.Get("mainServer");

            using (var receiver = new PullSocket(">tcp://localhost:80"))
                using (var sender = new PushSocket(">tcp://localhost:400"))
                {
                    //process tasks forever
                    while (true)
                    {
                        //workload from the vetilator is a simple delay
                        //to simulate some work being done, see
                        //Ventilator.csproj Proram.cs for the workload sent
                        //In real life some more meaningful work would be done
                        string workload = receiver.ReceiveFrameString();

                        //0 ... lower, 1... upper... 2..height
                        string[] workLoadArray = workload.Split(',');

                        var calculator = new Calculator();

                        var result = calculator.Calculate(Convert.ToInt32(workLoadArray[0]), Convert.ToInt32(workLoadArray[1]), Convert.ToInt32(workLoadArray[2]), 400);


                        byte[]          dataGame;
                        BinaryFormatter binaryFormatter = new BinaryFormatter();

                        using (var memoryStream = new MemoryStream())
                        {
                            binaryFormatter.Serialize(memoryStream, result);
                            dataGame = memoryStream.ToArray();
                        }

                        Console.WriteLine("Sending to Sink");
                        sender.SendFrame(dataGame);
                    }
                }
        }
        void StartServer()
        {
            Debug.Log("Start Server!");
            using (PullSocket pullSocket = new PullSocket())
                using (PublisherSocket publisherSocket = new PublisherSocket())
                {
                    pullSocket.Bind("tcp://*:20002");
                    publisherSocket.Bind("tcp://*:20001");

                    while (true)
                    {
                        string str = pullSocket.ReceiveFrameString();
                        Debug.Log("[Server] Get! :: " + str);
                        publisherSocket.SendFrame("Hello Client!");
                        Debug.Log("[Server] Send Hello Client!");
                    }
                }
        }
        static void Main(string[] args)
        {
            using (var priceValidator = new PullSocket("@tcp://localhost:11000"))
            {
                while (true)
                {
                    var message        = priceValidator.ReceiveFrameString();
                    var productMessage = Newtonsoft.Json.JsonConvert.DeserializeObject <ValidatedProductMessage>(message);

                    Console.WriteLine($"Product validated: {productMessage.Product.Name}");
                    Console.WriteLine($"Worker id: {productMessage.ProcessedBy}");
                    Console.WriteLine("Erros:");

                    foreach (var error in productMessage.Erros)
                    {
                        Console.WriteLine(error);
                    }
                }
            }
        }
Exemple #16
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        public void ContinousReceiveMessages()
        {
            var pullSocket = new PullSocket();

            pullSocket.Bind("tcp://*:" + RemoteServGr.NodePort);
            while (RemoteServGr.Running)
            {
                var msgJson = pullSocket.ReceiveFrameString();
                ReceiveMessage(msgJson);
            }
            var msg = new Message
            {
                MsgType       = MessageType.EndingProgram,
                SendingServer = RemoteServGr.NodeAddress
            };
            var messageWrapper = new RemoteDispatch(msg, null);

            RemoteServGr.SendQueue.Add(messageWrapper);
            pullSocket.Close();
        }
Exemple #17
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        static void Main(string[] args)
        {
            Console.WriteLine("====== WORKER ======");

            using (var pull = new PullSocket())
                using (var sink = new DealerSocket())
                {
                    pull.Connect("tcp://127.0.0.1:8888");
                    sink.Connect("tcp://127.0.0.1:7777");

                    while (true)
                    {
                        var workload = pull.ReceiveFrameString();
                        Thread.Sleep(int.Parse(workload));

                        Console.WriteLine("Sending to Sink");
                        sink.SendFrame(string.Empty);
                    }
                }
        }
Exemple #18
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        public static void ThreadProc(object obj)
        {
            //string[] args = ToStringArray(obj);
            var source = obj as CancellationTokenSource;

            using (var recv = new PullSocket())
            {
                recv.Bind("tcp://127.0.0.1:5489");
                while (true)
                {
                    string temp = recv.ReceiveFrameString();  // To receive a flag from external programs to stop the service
                    if (!bool.Parse(temp))
                    {
                        Console.WriteLine("STOP");
                        source.Cancel();
                        source.Dispose();
                        //CreateHostBuilder(args).Build().StopAsync().Wait();
                        Console.WriteLine("DONE Stop");
                        break;  // Jump out of the loop as soon as the service is stopped.
                    }
                }
            }
        }
        static void Main(string[] args)
        {
            var identity = Guid.NewGuid().ToString();

            using (var receiver = new PullSocket(">tcp://localhost:10000"))
                using (var validationPush = new PushSocket(">tcp://localhost:11000"))
                {
                    while (true)
                    {
                        var productTohavePriceValidated = receiver.ReceiveFrameString();
                        Console.WriteLine(productTohavePriceValidated);

                        var product = Newtonsoft.Json.JsonConvert.DeserializeObject <Product>(productTohavePriceValidated);

                        var validationMessages = ValidateProduct(product);
                        validationMessages.AddRange(ValidatePrice(product));

                        var message = new ValidatedProductMessage(product, identity, validationMessages.ToArray());

                        validationPush.SendFrame(Newtonsoft.Json.JsonConvert.SerializeObject(message));
                    }
                }
        }
        public static void Main(string[] args)
        {
            Console.WriteLine("====== WORKER ======");
            using (var receiver = new PullSocket(">tcp://localhost:80"))
                using (var sender = new PushSocket(">tcp://localhost:400"))
                {
                    //process tasks forever
                    while (true)
                    {
                        string workload = receiver.ReceiveFrameString();
                        Console.WriteLine("got");
                        string[] values = workload.Split(',');

                        double xReminder = -2 + ((double)Int32.Parse(values[0]) * 0.013);

                        MandlBrotCalcer calcer = new MandlBrotCalcer();

                        List <(int, int, int)> list = calcer.CalcPart(Int32.Parse(values[0]), Int32.Parse(values[1]), 0, Int32.Parse(values[2]), 18, 4, xReminder, 1.2, 0.013);

                        BinaryFormatter binaryFormatter = new BinaryFormatter();

                        byte[] listBytes;

                        using (var memoryStream = new MemoryStream())
                        {
                            binaryFormatter.Serialize(memoryStream, list);
                            listBytes = memoryStream.ToArray();
                        }

                        sender.SendFrame(listBytes);

                        Console.WriteLine("Sending to Sink");
                        sender.SendFrame(string.Empty);
                    }
                }
        }
        static void Main(string[] seed)
        {
            Console.WriteLine("====== FRONT QUEUE ======");
            using var toWorkers     = new PushSocket($"@{ThreadSafeFactory.FrontQueue}");
            using var fromBackQueue = new PullSocket($">{ThreadSafeFactory.BackQueue}");

            Console.WriteLine("Socket initialized");

            foreach (var s in seed)
            {
                _urlQueue.Enqueue(new UrlQueueItem {
                    Url = s
                });
            }
            var backQueueProcessor = Task.Run(() =>
            {
                // Receive from backqueue
                while (true)
                {
                    Console.WriteLine($"Waiting for backqueue");
                    var workload = fromBackQueue.ReceiveFrameString();
                    Console.WriteLine($"Got message from backqueue");
                    UrlQueueItem queueItem = new UrlQueueItem
                    {
                        Url = workload
                    };
                    if (!_urlVisiting.ContainsKey(queueItem.Url))
                    {
                        _urlQueue.Enqueue(queueItem);
                    }
                    else
                    {
                        Console.WriteLine($"Url {queueItem.Url} already sent to processing");
                    }
                }
            });

            var frontQueueProcessor = Task.Run(() =>
            {
                // send to worker
                while (true)
                {
                    do
                    {
                        Parallel.For(0, maxThread, (threadIndex) =>
                        {
                            //while (_urlQueue.IsEmpty)
                            //{
                            //    Task.Delay(5000).Wait();
                            //}
                            if (_urlQueue.TryDequeue(out UrlQueueItem url))
                            {
                                if (_politenessPolicy.CanIGoThere(url, out long crawlDelay))
                                {
                                    Task.Delay((int)crawlDelay).Wait();
                                    url.QueuedOn = DateTime.UtcNow;
                                    Console.WriteLine($"Sending to worker [{url.Url}]");
                                    toWorkers.SendFrame(url.ToJson());
                                    Console.WriteLine($"Sent to worker");
                                    _urlVisiting.AddOrUpdate(url.Url.ToLower(), false, (key, val) => false);
                                }
                            }
                        });
                    } while (!_urlQueue.IsEmpty);
                }
            });
Exemple #22
0
        static void Main(string[] args)
        {
            using (var receiver = new PullSocket(">tcp://localhost:5557"))
                using (var sender = new PushSocket(">tcp://localhost:5558"))
                    using (Model.ticketClassesDataContext = new TicketClassesDataContext("Server=(localdb)\\ProjectsV13;Database=TicketsDatabase;")) {
                        Model.ticketClassesDataContext.Connection.Open();
                        var result = Model.ticketClassesDataContext.ExecuteQuery <Station>(
                            @"SELECT * FROM dbo.Station"
                            );
                        foreach (var r in result)
                        {
                            ;
                        }

                        while (true)
                        {
                            Console.WriteLine("waiting");

                            var      message = receiver.ReceiveFrameString();
                            string[] vs      = message.Split(';');
                            Console.WriteLine("Received {0}", message);

                            byte[] answer = { };
                            switch (vs[0])
                            {
                            case "GetDistance":
                                answer = Controller.GetDistance(vs);
                                break;

                            case "GetAllStationNames":
                                answer = Controller.GetAllStationNames(vs);
                                break;

                            case "CheckIfLoginAvailable":
                                answer = Controller.GetUserByLogin(vs);
                                break;

                            case "AddUser":
                                answer = Controller.AddUser(vs);
                                break;

                            case "Authenticate":
                                answer = Controller.Authenticate(vs);
                                break;

                            case "BuyTicket":
                                answer = Controller.BuyTicket(vs);
                                break;

                            case "GetTicketsByUser":
                                answer = Controller.GetTicketsByUser(vs);
                                break;
                            }

                            Thread.Sleep(1000);
                            //Send an answer

                            //Console.WriteLine("Sending: " + Encoding.ASCII.GetString(answer));

                            sender.SendFrame(answer);
                        }
                    }
        }
Exemple #23
0
        static void Main(string[] args)
        {
            const int POISON_QUEUE_MAX_TRY = 5;

            Console.WriteLine("====== WORKER ======");

            using var fromFrontQueue = new PullSocket($">{ThreadSafeFactory.FrontQueue}");
            using var toBackQueue    = new PushSocket($">{ThreadSafeFactory.BackUrlQueue}");
            using var toPoisonQueue  = new PushSocket($">{ThreadSafeFactory.BackPosionQueue}");

            Console.WriteLine("Initialized Socket");
            //process tasks forever
            var frontQueueProcessor = Task.Run(() =>
            {
                while (true)
                {
                    try
                    {
                        Console.WriteLine($"Waiting for front queue");
                        var workload           = fromFrontQueue.ReceiveFrameString();
                        UrlQueueItem queueItem = workload.FromJson <UrlQueueItem>();
                        Console.WriteLine($"Request from frontqueue {queueItem.Url}");
                        _urlQueue.Enqueue(queueItem);
                    }
                    catch (Exception ex)
                    {
                        Console.WriteLine($"Error in Front Queue Processor {ex.Message}");
                    }
                }
            });

            var processUrlTask = Task.Run(() =>
            {
                while (true)
                {
                    Parallel.For(0, 2 * maxThread / 3, (threadIndex) =>
                    {
                        //while (_urlQueue.IsEmpty)
                        //{
                        //    Task.Delay(5000).Wait();
                        //}
                        if (_urlQueue.TryDequeue(out UrlQueueItem url))
                        {
                            Console.WriteLine($"Processing {url.Url}");
                            url.CrawlStart = DateTime.UtcNow;
                            try
                            {
                                foreach (var childUrl in _htmlRenderer.FindChildLinks(url))
                                {
                                    if (!_visitedUrls.ContainsKey(childUrl))
                                    {
                                        _visitedUrls.TryAdd(childUrl, false);
                                        Console.WriteLine($"Sending to backqueue");
                                        toBackQueue.SendFrame(childUrl);
                                        Console.WriteLine($"Sending to backqueue");
                                    }
                                }
                            }
                            catch (Exception ex)
                            {
                                var u           = url.Clone() as UrlPosionQueueItem;
                                u.TryCount      = 0;
                                u.CrawlFinished = DateTime.UtcNow;
                                u.Errors        = new List <string>
                                {
                                    ex.Message + "|" + ex?.InnerException?.Message
                                };
                                _urlPoisonQueue.Enqueue(u);
                                Console.WriteLine($"Error in Url Processor {ex.Message}");
                            }
                            url.CrawlFinished = DateTime.UtcNow;
                        }
                    });
                }