subprotocol is not returned in WebSocket Upgrade / Accept Response

[Tratcher]

From @rposener on April 27, 2016 20:51

the following JS:
var exampleSocket = new WebSocket("ws://" + window.location.host, "test");
when accepted by:
WebSocket webSocket = await httpContext.WebSockets.AcceptWebSocketAsync("test");
does not include the header value:
Sec-WebSocket-Protocol:test

even though it should per spec.

Copied from original issue: aspnet/WebSockets#79

[Tratcher]

From @muratg on April 28, 2016 16:40

Tentatively putting this in 1.0.0. We'll investigate after RC2 ships.

[Tratcher]

From @tmds on April 28, 2016 16:50

@rposener what server are you using?

[Tratcher]

From @rposener on April 28, 2016 17:1

As best I understand it's kestral hosted within IISExpress (project is targeting dnx451 and dnxcore50) currently for rc1-update2

[Tratcher]

From @tmds on April 28, 2016 17:59

What should happen:
the value you give in AcceptWebSocketAsync should be set in the WebSocketAccept context here.
Then read from the context here, passed on to GenerateResponseHeaders to end up in the header IEnumerable here, which then becomes part of the response headers here.

Stepping through AcceptAsync may give you an idea of what the issue is. If you check out Microsoft.AspNetCore.WebSockets.Server and add it to your 'src' folder, you should be able to set a breakpoint in that method.

[Tratcher]

Does it work if you run Kestrel directly without IISExpress?

[Tratcher]

From @rposener on April 29, 2016 21:22

Yes, works fine once IISExpress is removed from the mix. Is there a way to allow that to pass through?

[Tratcher]

We'll have to investigate. @pan-wang, can you take a look?

[Tratcher]

From @muratg on July 25, 2016 22:4

@anurse Does SignalR use subprotocol in websockets?