Error handling with signalr

[KlemensGenetec]

Hello,

I am using YARP for forwarding both http and WS. When using WS the connections can be very long lived and sometimes the connection to the client gets broken due to bad connections etc. When that is happening, I get an exception like this

Yarp.ReverseProxy.Forwarder.HttpForwarder: Information: UpgradeRequestClient: The client reported an error when copying the upgraded request body.

Microsoft.AspNetCore.Connections.ConnectionResetException: An existing connection was forcibly closed by the remote host.
 ---> System.Net.Sockets.SocketException (10054): An existing connection was forcibly closed by the remote host.
   at Microsoft.AspNetCore.Server.Kestrel.Transport.Sockets.Internal.SocketAwaitableEventArgs.<GetResult>g__ThrowSocketException|5_0(SocketError e)
   at Microsoft.AspNetCore.Server.Kestrel.Transport.Sockets.Internal.SocketAwaitableEventArgs.GetResult(Int16 token)
   at Microsoft.AspNetCore.Server.Kestrel.Transport.Sockets.Internal.SocketConnection.DoReceive()
   --- End of inner exception stack trace ---
   at System.IO.Pipelines.Pipe.GetReadResult(ReadResult& result)
   at System.IO.Pipelines.Pipe.GetReadAsyncResult()
   at System.IO.Pipelines.Pipe.DefaultPipeReader.GetResult(Int16 token)
   at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.DuplexPipeStream.ReadAsyncInternal(Memory`1 destination, CancellationToken cancellationToken)
   at System.Runtime.CompilerServices.PoolingAsyncValueTaskMethodBuilder`1.StateMachineBox`1.System.Threading.Tasks.Sources.IValueTaskSource<TResult>.GetResult(Int16 token)
   at System.Net.Security.SslStream.ReadAsyncInternal[TIOAdapter](TIOAdapter adapter, Memory`1 buffer)
   at System.IO.Pipelines.StreamPipeReader.<ReadAsync>g__Core|36_0(StreamPipeReader reader, CancellationTokenSource tokenSource, CancellationToken cancellationToken)
   at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http.Http1UpgradeMessageBody.ReadAsyncInternalAwaited(ValueTask`1 readTask, CancellationToken cancellationToken)
   at System.Runtime.CompilerServices.PoolingAsyncValueTaskMethodBuilder`1.StateMachineBox`1.System.Threading.Tasks.Sources.IValueTaskSource<TResult>.GetResult(Int16 token)
   at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http.HttpRequestStream.ReadAsyncInternal(Memory`1 destination, CancellationToken cancellationToken)
   at Yarp.ReverseProxy.Forwarder.StreamCopier.CopyAsync(Stream input, Stream output, Int64 promisedContentLength, StreamCopierTelemetry telemetry, ActivityCancellationTokenSource activityToken, CancellationToken cancellation)

That is not a problem for the client since the client is already gone, but i want to change the response code for logging in App Insight from 500 to 499. I tried that with UseExceptionHandler but it is not called as I would have expected.

Any other place where I could change that?

[Tratcher]

The status code can't be modified after the response has started (e.g. after the upgrade). I'm surprised you're even seeing a 500 in the logs? It should be a 101.

[Tratcher]

UseExceptionHandler also no-ops after the response has started since it's not possible to replace the response.

[KlemensGenetec]

That is strange. Maybe ill need to look at the App Insight messages directly then.
Thanks a lot for the feedback!