Middleware for Batch HTTP Requests

Hi,

We are trying to implement middleware that will support batch requests. My current approach is to create a new http context (a type derived from DefaultHttpContext) for each sub request and execute my application pipeline for each sub request/context. I've got this working in a very basic form by having the batch middleware as the first middleware in my pipeline. In the batch middleware I begin execution of the remainder of the pipeline via the "next" request delegate using the new contexts created for each sub request. I have added or replaced request features as needed however when it comes to the IHttpResponseFeature I'm having difficulties with callbacks that are added via OnStarting or OnCompleted. I'm not sure when or where I should invoke the callbacks during execution of the pipeline.

I'd also like to know if there is a better approach to batching in ASP.NET core that does not require me to implement a full set of request features? :)

Thanks and Regards,
Brian.