Enable HTTP/2 & Push Promise

[Tratcher]

Edit: Proof of concept provided below https://github.com/aspnet/HttpSysServer/issues/106#issuecomment-291283012

How do we detect if the request is HTTP/2 before calling the Push method?

Also, should/can we expose things like request priority?

Fowler has asked us to set the HttpContext.Request.Protocol to "http/2" rather than it's current "http/1.1". HttpClient is doing something similar.

Response headers and body can be streamlined. HTTP/2 does not require us to manually chunk the response. All responses are treated like the old 1.0 connection:close mode.

[Tratcher]

https://msdn.microsoft.com/en-us/library/windows/desktop/mt219053(v=vs.85).aspx

[muratg]

@DamianEdwards Do we want HTTP/2 in WebListener?

(just for comparison - we won't be doing it in Kestrel any time soon)

cc @shirhatti

[DamianEdwards]

Not a high priority for now. Backlog it until we get more customers asking for it.

[Tratcher]

RE: aspnet/HttpAbstractions#371

[Tratcher]

The HTTP_REQUEST_FLAG_HTTP2 flag was added to HTTP_REQUEST.Flags some time after Win10 RTM.
https://msdn.microsoft.com/en-us/library/windows/desktop/aa364612(v=vs.85).aspx

[darrelmiller]

Enabling HTTP/2 for WebListener would allow API Management to support HTTP/2 and we have internal and external customers asking for it.

[Tratcher]

@darrelmiller HTTP/2 is already available (Win10), no changes were required, only PushPromise is missing.

[darrelmiller]

I just tried making a HTTP/2 request using HttpClient with WinHttpHandler and WebListener hosted using Damian's OwinWebListenerHost and it wasn't working. Maybe I'm just doing it wrong.

[Tratcher]

A) SSL is required. B) it's hard to tell if you succeeded, nothing in the server data structures tells you. Your best bet is to use a browser and its debugger tools.

[darrelmiller]

Thanks. I was just being dense. It is making HTTP/2 requests now. Do I actually need to migrate to WebListener, or would HttpListener work automatically too?

[Tratcher]

WebListener, HttpListener and IIS all inherit the same HTTP/2 functionality from Http.Sys.

[damianh]

@darrelmiller OwinWebListenerHost is fork of the katana HttpListener impl. It may need some changes to support HTTP/2...

[darrelmiller]

@damianh It did work, but I actually didn't need to change to WebListener at all. HttpListener worked just fine with HTTP/2.

[tpeczek]

Hi,

I did an implementation of HTTP/2 with Server Push for HttpSysServer here and described it here. Please let me know if this could be a valuable pull request (if the design is in line with team approach and this is a right time). Of course I would first make a pull request with IHttp2Feature to HttpAbstractions as it seem to belong there.

[Tratcher]

@tpeczek Looks like a good start. I think you duplicated existing code in several places (e.g. IndexOfKnownHeader).

I don't think we'd merge it until we look at the whole end-to-end, especially for the Feature interface. aspnet/HttpAbstractions#371. We want to make sure to expose everything we need to and that it works well for both HttpSysServer and Kestrel.