HttpContext RequestAborted no longer works.

[blogcraft]

Describe the bug

Since .NET 6, the HttpContext.RequestAborted does not updates when the request is cancelled. This used to work with .NET 5.
IsCancellationRequested stays in false even tho the request has been canceled and CanBeCancelled is set to true.

To Reproduce

I started a .NET 6 Angular project and created an HTTP GET request and subscribe to it, the Request is in an infinite loop intentionally so it can only be ended by the cancellation token. Also have a subject to cancel the request with an other button.

In .NET 5 this works flawlessly. In .NET 6 its unusable.

An Example Repo can be found here: https://github.com/blogcraft/TestCancel

Exceptions (if any)

Further technical details

• ASP.NET Core version: .NET 6.0.100
• The IDE (VS / VS Code/ VS4Mac) you're running on, and its version: VS Code
• Include the output of dotnet --info:

SDK de .NET (que refleje cualquier global.json): Version: 6.0.100 Commit: 9e8b04bbff

Entorno de tiempo de ejecución:
OS Name: Windows
OS Version: 10.0.22000
OS Platform: Windows
RID: win10-x64
Base Path: C:\Program Files\dotnet\sdk\6.0.100\

Host (useful for support):
Version: 6.0.0
Commit: 4822e3c3aa

.NET SDKs installed:
3.1.415 [C:\Program Files\dotnet\sdk]
5.0.401 [C:\Program Files\dotnet\sdk]
6.0.100 [C:\Program Files\dotnet\sdk]

.NET runtimes installed:
Microsoft.AspNetCore.App 3.1.21 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 5.0.10 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 6.0.0 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.NETCore.App 3.1.21 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 5.0.10 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 6.0.0 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.WindowsDesktop.App 3.1.21 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 5.0.10 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 6.0.0 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

To install additional .NET runtimes or SDKs:
https://aka.ms/dotnet-download

[davidfowl]

cc @stephentoub, just in case there's any insight here.

[stephentoub]

just in case there's any insight here.

Haven't tried the repro, but if token.CanBeCanceled is true and token.IsCancellationRequested is false, it simply sounds like no one is canceling the CancellationTokenSource.

[martincostello]

Could it be maybe something to do with the CancellationTokenSource pooling/re-use that was added in 6.0?

[davidfowl]

Could it be maybe something to do with the CancellationTokenSource pooling/re-use that was added in 6.0?

Yes it could be. The change was very small but I haven't spent any time investigating it to see if there's a bug somewhere.

[davidfowl]

@blogcraft can you verify the HTTP version you are using? Is it HTTP/2 or HTTP/1.1

[blogcraft]

@davidfowl Can You help me with that? My development environment I use the project as is (just the same as I used with .NET 5). Is there a way to force HTTP/2?
In my production environment I use an Azure AppService that has always been configured tu use HTTP 2.0.

[Tratcher]

@javiercn I think this is because of the new SPA proxy in 6.0, the cancellation doesn't flow through to the server. Can you take a look?