How to split a large request into smaller ones, then returning a response by merging smaller responses, In PipelineBehavior

[mjalil]

Hi,
I have a request like this:

public class TimeSerriesQuery 
{
    public DateTime From {get; set;}
    public DateTime To {get; set;}
}

and a response like this:

public class TimeSerries {
    public class DataPoint
    {
        public DateTime Time {get; set;}
        public double value {get; set;}
    }

    public DateTime LastTime {get; set;}
    public DataPoint[] DataPoints {get; set;}
}

I need to implement a IPipelineBehavior that split a TimeSerriesQuery with large time period into some queries with smaller time periods ,then send those requests to next handler in the pipeline, and then merge all small responses and return the final big response

I think the only possible way is to mutate the request to a smaller period and await on next, then mutate again and await again on next and do this until the whole period responses is ready, then merge them.
It seems it is not possible to call next multiple times concurrently with multiple split requests

How can I do that?

[jbogard]

You'd need to design your own solution inside a single PipelineBehavior. Delegate to some other interfaces and do this yourself. There's no out-of-the-box solution here.

The request exception actions/handlers are in a similar boat, that's why there's a separate interface for them and a behavior that coordinates calling into those separate behaviors.

[mjalil]

Jimmy,

After your comment on request exception actions/handlers, I checked the source of exception actions/handlers to see some sample code. I've found a mistake and requested pull #739

Thank you

[KurogamiLight3303]

Hi, to solve the problem its not easy for you to create a handler for your TimeSerriesQuery that if the time periods is too large split the periods into smaller TimeSerriesQuery and then send it with
Task.WhenAll(_mediator.Send(subquery1), _mediator.Send(subquery2));,?

[mjalil]

Task.WhenAll(_mediator.Send(subquery1), _mediator.Send(subquery2));

yes, that makes sense. thank you 👍