Bdtjtk

I want to find duplicate messages in ServiceBusTopics.Below is my logic.If I find any duplicate message am adding to the list and sending to another service bus topic. But I wasn't able to read all the service bus messages that are present in the subscription before looping through the list.I want to read all the messages from the sevicebus and then loop through it.I'm not sure how should I stop the execution of loops until I read all the messages from suscription

    private static string _serviceBusConn = "servicebusconnectionstring";

    private static string _serviceBustopic = "topic1";

    private static string _topic = "test_v1";



    static void Main(string args)

    {

        IList<string> items = new List<string>();

        int count; 

        IList<string> itemsRepeated = new List<string>();



        var subClient = SubscriptionClient.CreateFromConnectionString(_serviceBusConn, _serviceBustopic, "DevTest");



        subClient.OnMessage(m =>

        {

            Stream stream = m.GetBody<Stream>();

            StreamReader reader = new StreamReader(stream);

            string s = reader.ReadToEnd();



            Console.WriteLine(s);



            items.Add(s);



        });





        List<string> copy1= new List<string>(items);

        List<string> copy2 = new List<string>(items);





        foreach (var item in copy1)

        {

            count = 0;

            foreach (var itemtopic in copy2)

            {

                count++;

                Console.WriteLine("{0}{1}{2}", items, itemtopic, count);

                if (item.Equals(itemtopic))

                {

                    count++;

                }



                if (count > 1)

                {

                    Console.WriteLine(count);

                    itemsRepeated.Add(itemtopic);

                }

            }

        }

        foreach (var repeateditem in itemsRepeated)

        {

            SendMessage(repeateditem);

        }



    }



    static void SendMessage(string message)

        {

            var topicClient = TopicClient.CreateFromConnectionString(_serviceBusConn, _topic);

            var msg = new BrokeredMessage(message);

            topicClient.Send(msg);

        }

You can use ReceiveBatch(Int32) method to receive messages from a topic subscription in a batch. You can get the number of messages in a topic subscription using Getsubscription() method of namespace manager.

var namespaceManager = NamespaceManager.CreateFromConnectionString(connnectionString);

var subscriptionDescription = namespaceManager.GetSubscription(topicName, subscriptionName);

var totalMessageCount= subscriptionDescription .MessageCount;

Now you can call the ReceiveBatch(minimumMessageCount) within a loop and terminate the loop when the received message count reaches the totalMessageCount.

int receivedMessageCount = 0;

List<BrokeredMessage> MessageList = new List<BrokeredMessage>();

do{

var messageList = subClient.ReceiveBatch(100);

receivedMessageCount += messageList.Count;

MessageList.AddRange(messageList); 

}while(receivedMessageCount < totalMessageCount);

Now the MessageList will have all the messages in the topic subscription.You can use your custom logic on the message list to perform duplicate detection and forward that to another subscription.

Note: To receive all the messages from a ServiceBusTopic, you have to receive all the messages from all the topic subscriptions within that topic.

 if (count > 1)

                {

                    Console.WriteLine(count);

                    itemsRepeated.Add(itemtopic);

                }

you can break the loop by using break like this

   if (count > 1)

                        {

                            Console.WriteLine(count);

                            itemsRepeated.Add(itemtopic);

                            break;

                        }