SignalR http2 support

[WeihanLi]

Does SignalR support HTTP2 now? I can see the WebSocket is supported over http2, #7801

while seems I could not make it work on SignalR even with a customized http handler, is this already supported or not yet?
If supported, is there a sample for using SignalR with HTTP2?

[BrennanConroy]

Yes it's supported. https://learn.microsoft.com/aspnet/core/fundamentals/websockets?view=aspnetcore-9.0#http2-websockets-support

It should just work automatically in the browser, unless you have a proxy in the way that doesn't support it.

With the .NET client you would need to set https://learn.microsoft.com/aspnet/core/signalr/configuration?view=aspnetcore-9.0&tabs=dotnet#configure-additional-options WebSocketConfiguration to set the ClientWebSocketOptions.HttpVersion value to Http/2 or higher.

[BrennanConroy]

You're using http, not https. Http/2 doesn't work over http without extra work.

[WeihanLi]

Works when using https and negotiation, thanks very much

Same error when SkipNegotiation, is this a bug when SkipNegotiation, should I create an issue for this?

You're using http, not https. Http/2 doesn't work over http without extra work.

is there a sample for using http to show the additional setup?

[BrennanConroy]

gRPC has some information about insecure http/2
https://learn.microsoft.com/aspnet/core/grpc/troubleshoot?view=aspnetcore-8.0#call-insecure-grpc-services-with-net-core-client

The SkipNegotation part is a bug.

[WeihanLi]

https://learn.microsoft.com/en-us/aspnet/core/grpc/troubleshoot?view=aspnetcore-3.1#call-insecure-grpc-services-with-net-core-client-2

The System.Net.Http.SocketsHttpHandler.Http2UnencryptedSupport switch is only required for .NET Core 3.x. It does nothing in .NET 5 and isn't required.

From the document, seems this is not required for .NET 5+

And I still get the same 400 error when adding AppContext.SetSwitch("System.Net.Http.SocketsHttpHandler.Http2UnencryptedSupport", true);, is there something I miss? Does any other config need to be updated?

[BrennanConroy]

is there something I miss? Does any other config need to be updated?

Probably. I don't know how to do it, just pointing you at some resources that might help.