Fix: return Task.CompletedTask when Saga not found in TimeoutMessage handlers

[Damix48]

I was trying the Saga example provided in the docs but the generation doesn't not compile because there an empty return instead of a return Task.Complete.

I'm not 100% sure that this is the correct fix.

    // START: OrderTimeoutHandler477439855
    public class OrderTimeoutHandler477439855 : Wolverine.Runtime.Handlers.MessageHandler
    {
        private readonly Microsoft.Extensions.Logging.ILogger<SagaTest.Order> _logger;
        private readonly Wolverine.Persistence.Sagas.InMemorySagaPersistor _inMemorySagaPersistor;

        public OrderTimeoutHandler477439855(Microsoft.Extensions.Logging.ILogger<SagaTest.Order> logger, Wolverine.Persistence.Sagas.InMemorySagaPersistor inMemorySagaPersistor)
        {
            _logger = logger;
            _inMemorySagaPersistor = inMemorySagaPersistor;
        }



        public override async System.Threading.Tasks.Task HandleAsync(Wolverine.Runtime.MessageContext context, System.Threading.CancellationToken cancellation)
        {
            // The actual message body
            var orderTimeout = (SagaTest.OrderTimeout)context.Envelope.Message;

            string sagaId = context.Envelope.SagaId ?? orderTimeout.Id;
            if (string.IsNullOrEmpty(sagaId)) throw new Wolverine.Persistence.Sagas.IndeterminateSagaStateIdException(context.Envelope);
            var order = _inMemorySagaPersistor.Load<SagaTest.Order>(sagaId);
            if (order == null)
            {
                return; <-- HERE should return Task.Completed
            }

            else
            {

                // The actual message execution
                await order.Handle(orderTimeout, _logger).ConfigureAwait(false);

                // Delete the saga if completed, otherwise update it
                if (order.IsCompleted())
                {
                    _inMemorySagaPersistor.Delete<SagaTest.Order>(sagaId);
                }

                else
                {
                    _inMemorySagaPersistor.Store<SagaTest.Order>(order);
                }

                // No unit of work
            }

        }

    }

    // END: OrderTimeoutHandler477439855

[jeremydmiller]

@Damix48 Thanks for taking that on, but it's more complicated than that. that change might fix that particular case, but could easily break others. I'll take a look at it by 3.13. Which example are you talking about?

You have to look up the stack of Frame operations to "know" if there are any async operations that would make the method async/await or if you should return Task.CompletedTask

[Damix48]

This example: https://wolverinefx.net/guide/durability/sagas.html#your-first-saga

I just copy paste but without the Marten stuff

[Damix48]

The handler generated derives from MessageHandler that has

public abstract Task HandleAsync(MessageContext context, CancellationToken cancellation);

so when is overridden, I think it should always return a Task.CompletedTask. But as you said probably this fix only this case.