I have an Azure Message Bus Topic. I have one "Session enabled" Azure Message Bus Consumer for this Topic. I have around 3 Worker Services that are using the same Consumer. So the work is shared between these 3 Workers. The Messages which are sent to the consumer need to be ordered, thats why I am using the "Session Feature" on the Consumer.

I believe that on a first Message, the Session of the Message gets bind to a Worker Service. For certain Reasons I want to abandon not only a Message but also the session so that it can be picked up by another of the 3 Worker Services.

My questions:

1. Is this possible?
2. If yes how can I do this in the code?
3. Is there something like "Accept Session Or Not" Handler which kicks in when Message received?

See code below:

        private void SetupServiceBusSessionProcessors2()
        {
            var busProcessorOptions = new ServiceBusSessionProcessorOptions();

            var busProcessor = _busClient.CreateSessionProcessor("fooTopic", "fooSubscription", busProcessorOptions);

            busProcessor.ProcessMessageAsync  = args => ProcessSessionMessageHandler2(args);
        }
        
        private async Task ProcessSessionMessageHandler2(ProcessSessionMessageEventArgs args)
        {
            if (false) // Condition here which Abandons Message AND Session
            {
                // the following line of code seems only to abandon the Message
                // but it seems like the session is locked to this service
                // i want that other services which are listening via the same consumer can try to handle the session
                await args.AbandonMessageAsync(args.Message);
            }
        }

CodePudding user response：

This is possible in version 7.3.0-beta.1 using the ReleaseSession method on the event args. Note that this is a beta version so the API is subject to change before there is a stable release.

CodePudding user response：

1. Is this possible?

No, it is not possible to abandon the session.

When multiple concurrent receivers start receiving messages from the Queue, the messages belonging to a specific session are dispatched to the specific receiver that is currently holding a lock on that session.

With that operation, huge message stream residing in a Queue or Subscription is de-multiplexed to different receivers and those receivers can be on different machines, since the lock management happens service-side, inside Service Bus.

Abandoning a message causes the same message to be served again with the next receive operation.

The client application, sending the message must set a unique identifier as a ‘SessionId’ in each message that is being sent. Now, the receiving application should create Session Receiver using the respective ‘SessionId’ and receive the set of messages related to the specific client.

By this way, all the messages corresponding to a specific client can be received by a specific single receiver.

You can refer this doc for more information.