SignalR websocket closure not handled well - am I missing something?

[omaristalis]

I have a test setup, all localhost, consisting of a reverse-proxy service, a SignalR service, and a SignalR client:

Client -> reverse-proxy -> service.

Everything works great until I hit Ctrl+C on my client. An exception is generated in the reverse proxy, but the connection to the SignalR service is maintained, and my service keeps pushing updates back through the connection (or is trying to).

My expectation was that when the websocket was closed from the client, the reverse proxy would close the websocket to the server.

Any help is welcome!

Note that if I quit the client cleanly, it does disconnect cleanly all the way back to the service.

The exception I see is:

fail: Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware[1] An unhandled exception has occurred while executing the request. System.OperationCanceledException: The operation was canceled. at System.Threading.CancellationToken.ThrowOperationCanceledException() at System.IO.Pipelines.Pipe.GetReadAsyncResult() at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.DuplexPipeStream.ReadAsyncInternal(Memory1 destination, CancellationToken cancellationToken)
at System.Net.Security.SslStream.g__InternalFillBufferAsync|215_0[TReadAdapter](TReadAdapter adap, ValueTask1 task, Int32 min, Int32 initial) at System.Net.Security.SslStream.ReadAsyncInternal[TReadAdapter](TReadAdapter adapter, Memory1 buffer)
at System.IO.Pipelines.StreamPipeReader.ReadAsync(CancellationToken cancellationToken)
at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http.HttpRequestStream.ReadAsyncInternal(Memory1 buffer, CancellationToken cancellationToken) at Microsoft.ReverseProxy.Service.Proxy.StreamCopier.CopyAsync(Stream source, Stream destination, CancellationToken cancellation) at Microsoft.ReverseProxy.Service.Proxy.HttpProxy.UpgradableProxyAsync(HttpContext context, IHttpUpgradeFeature upgradeFeature, HttpRequestMessage upstreamRequest, Transforms transforms, HttpMessageInvoker httpClient, ProxyTelemetryContext proxyTelemetryContext, CancellationToken shortCancellation, CancellationToken longCancellation) at Microsoft.ReverseProxy.Telemetry.TextOperationLogger1.ExecuteAsync(String operationName, Func1 action) at Microsoft.ReverseProxy.Middleware.ProxyInvokerMiddleware.Invoke(HttpContext context) at Microsoft.AspNetCore.Routing.EndpointMiddleware.<Invoke>g__AwaitRequestTask|6_0(Endpoint endpoint, Task requestTask, ILogger logger) at Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware.Invoke(HttpContext context) warn: Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware[2] The response has already started, the error page middleware will not be executed. fail: Microsoft.AspNetCore.Server.Kestrel[13] Connection id "0HM2L6133BAVR", Request id "0HM2L6133BAVR:00000001": An unhandled exception was thrown by the application. System.OperationCanceledException: The operation was canceled. at System.Threading.CancellationToken.ThrowOperationCanceledException() at System.IO.Pipelines.Pipe.GetReadAsyncResult() at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.DuplexPipeStream.ReadAsyncInternal(Memory1 destination, CancellationToken cancellationToken)
at System.Net.Security.SslStream.g__InternalFillBufferAsync|215_0[TReadAdapter](TReadAdapter adap, ValueTask1 task, Int32 min, Int32 initial) at System.Net.Security.SslStream.ReadAsyncInternal[TReadAdapter](TReadAdapter adapter, Memory1 buffer)
at System.IO.Pipelines.StreamPipeReader.ReadAsync(CancellationToken cancellationToken)
at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http.HttpRequestStream.ReadAsyncInternal(Memory1 buffer, CancellationToken cancellationToken) at Microsoft.ReverseProxy.Service.Proxy.StreamCopier.CopyAsync(Stream source, Stream destination, CancellationToken cancellation) at Microsoft.ReverseProxy.Service.Proxy.HttpProxy.UpgradableProxyAsync(HttpContext context, IHttpUpgradeFeature upgradeFeature, HttpRequestMessage upstreamRequest, Transforms transforms, HttpMessageInvoker httpClient, ProxyTelemetryContext proxyTelemetryContext, CancellationToken shortCancellation, CancellationToken longCancellation) at Microsoft.ReverseProxy.Telemetry.TextOperationLogger1.ExecuteAsync(String operationName, Func1 action) at Microsoft.ReverseProxy.Middleware.ProxyInvokerMiddleware.Invoke(HttpContext context) at Microsoft.AspNetCore.Routing.EndpointMiddleware.<Invoke>g__AwaitRequestTask|6_0(Endpoint endpoint, Task requestTask, ILogger logger) at Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware.Invoke(HttpContext context) at Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware.Invoke(HttpContext context) at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http.HttpProtocol.ProcessRequests[TContext](IHttpApplication1 application)
info: Microsoft.AspNetCore.Hosting.Diagnostics[2]
Request finished in 266973.1019ms 101
dbug: Microsoft.AspNetCore.Server.Kestrel[2]
Connection id "0HM2L6133BAVR" stopped.`

[Tratcher]

I'm working on this now over at #406. I plan to get it into preview 5.

[omaristalis]

Perfect! Thanks for the speedy reply! 👍

[omaristalis]

Re-tested today with preview 5, and all looks good. Thanks again!