Pub/Sub w/Multiple Subscribers

Question

I’m having problems getting the message to multiple subscribers, the message comes into whatever client picks it up first. Basically, I have a Kiosk that when updated I want to notify everyone running our management center application that something has occurred on the Kiosk. Can anyone point me to a sample or tell me what I’m doing wrong?

Thanks for any assistance.

        private void CreateTopic()

        {

            var managementUri = ServiceBusEnvironment.CreateServiceUri("sb", ServiceBusNamespace, string.Empty);

            _namespaceManager = new NamespaceManager(managementUri, TokenProvider.CreateSharedSecretTokenProvider(ServiceBusIssuerName, ServiceBusIssuerKey));

            var topicDescription = new TopicDescription(_topicPath)

            {

                DefaultMessageTimeToLive = TimeSpan.FromMinutes(15),

                DuplicateDetectionHistoryTimeWindow = TimeSpan.FromMinutes(10),

                EnableBatchedOperations = true,

                RequiresDuplicateDetection = true

            };

            if (_namespaceManager.TopicExists(topicDescription.Path))

            {

                _namespaceManager.DeleteTopic(topicDescription.Path);

            }

            _namespaceManager.CreateTopic(topicDescription);

            SubDescription = _namespaceManager.CreateSubscription(_topicPath, "Kiosk");

        }

        private void Subscription()

        {

            var tokenProvider = TokenProvider.CreateSharedSecretTokenProvider(ServiceBusIssuerName, ServiceBusIssuerKey);

            var uri = ServiceBusEnvironment.CreateServiceUri("sb", ServiceBusNamespace, string.Empty);

            var messagingFactory = MessagingFactory.Create(uri, tokenProvider);

            var subscriptionClient = messagingFactory.CreateSubscriptionClient(_topicPath, "Kiosk");

            while (true)

            {

                var message = subscriptionClient.Receive();

                if (message != null)

                {

                    var data = message.GetBody<string>();

                    WriteText(data);

                    //message.Complete();

                }

            }

        }

        private void SendBrokeredMessage(string messageText)

        {

            var runtimeUri = ServiceBusEnvironment.CreateServiceUri("sb", ServiceBusNamespace, string.Empty);

            var messagingFactory = MessagingFactory.Create(runtimeUri, TokenProvider.CreateSharedSecretTokenProvider(ServiceBusIssuerName, ServiceBusIssuerKey));

            var topicClient = messagingFactory.CreateTopicClient(_topicPath);

            if (!String.IsNullOrEmpty(messageText))

            {

                var data = messageText;

                var message = new BrokeredMessage(data);

                message.Properties.Add(CategoryPropName, messageText);

                message.MessageId = "m_" + DateTime.Now.ToLongTimeString();

                try

                {

                    topicClient.Send(message);

                    txbMessage.Text = string.Empty;

                }

                catch (Exception ex)

                {

                    WriteText(ex.Message);

                }

            }

            else

            {

                txbMessage.Text = "Please enter a message!";

            }

        }

  

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Brian K. Williams

Answer 1

It appears that you have a single subscription, such that all the subscribers are competing for the same message. Each subscriber needs a separate unique subscription to get all the messages.

You can create separate subscriptions by suffixing the “Kiosk” with a unique identifier and later deleting the subscription when it is no longer needed.

Answer 2

Hi,

I have a sample on my blog were I route messages to multiple subscribers.

http://geekswithblogs.net/asmith/archive/2012/04/16/149332.aspx

Regards,

Alan

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Answer 3

Thanks for the help works perfect now, I was thinking it was more like SQL Subscriptions.

Azure ServiceBus is awesome…

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Brian K. Williams

Answer 4

Hey Alan…

Thanks for the help again..

Now that everything is working great with WPF client, I need to do the same with a Silverlight 5 application. Can you point me to a sample that explains the best way to accomplish this?

Thanks

-Brian