dotnet/runtime

HTTP/2 extended connect error message doesn't blame the server

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#111,470 opened on Jan 15, 2025

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area-System.Net.Httphelp wanted

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Description

Description

System.Net.Http.HttpRequestException: Failed to establish web socket connection over HTTP/2 because extended CONNECT is not supported. Try to downgrade the request version to HTTP/1.1.

Reproduction Steps

Conect to a websocket with Extended Connect

Expected behavior

Work?

Actual behavior

Exception

Regression?

No response

Known Workarounds

No response

Configuration

   conection = new ClientWebSocket();

   conection.Options.SetRequestHeader("Stream-Type", ",mystream");
   conection.Options.HttpVersion = HttpVersion.Version30;

   await conection.ConnectAsync(new Uri(webSocketUri), Net.client, CancellationToken.None);

Other information

No response

Contributor guide

Research direction
Inspect the error message generation in the HTTP/2 handler and determine if the server's lack of support should be indicated in the exception text.
Tech stack
csharp
Domain
networking
Issue type
Bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Needs investigation
Prerequisites
C#HTTP/2
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
40