kiota crashes with NullReferenceException after update

[bkoelman]

What are you generating using Kiota, clients or plugins?

API Client/SDK

In what context or format are you using Kiota?

Nuget tool

Client library/SDK language

Csharp

Describe the bug

After update from v1.21.0 to v1.22.3, kiota crashes with the following error on Ubuntu:

  crit: Kiota.Builder.KiotaBuilder[0]
        error generating the client: One or more errors occurred. (Object reference not set to an instance of an object.) (Object reference not set to an instance of an object.)

Expected behavior

No crash.

How to reproduce

Run the following command:

dotnet kiota generate --language CSharp --class-name RestrictedControllersClient --namespace-name OpenApiKiotaEndToEndTests.RestrictedControllers.GeneratedCode --output ./GeneratedCode --backing-store --exclude-backward-compatible --clean-output --clear-cache --log-level Error --openapi ./swagger.g.json

Open API description file

Contents of swagger.g.json:

https://github.com/json-api-dotnet/JsonApiDotNetCore/blob/2212fc2c685446bebf86c905814a014f1a521cbd/test/OpenApiTests/RestrictedControllers/GeneratedSwagger/swagger.g.json

Kiota Version

1.22.3

Latest Kiota version known to work for scenario above?(Not required)

1.21.0

Known Workarounds

None

Configuration

Ubuntu 24.04.1 LTS (GitHub Actions runner)

Debug output

No response

Other information

No response

[andrueastman]

Thanks for raising this @bkoelman

Unfourtunately, I'm not able to replicate the error using the openApi description and the arguments you provided.
Are you able to set the --log-level to Debug and share a trace to help us undestand better?
Is the failure consistent or does the success of the generation here flaky?

[bkoelman]

I'm unable to reproduce it anymore. I've tried 7x with debug switch on Windows/Ubuntu/macOS, then 6x without debug switch.

It would be helpful to dump the stack trace on the console in such cases.

[baywet]

Stack traces are enabled by default when built in debug. But we don't distribute debug builds.
We disabled it in release builds because we had received feedback a while ago that it was confusing for users.

Let us know if you have any additional comments or questions.

[bkoelman]

Well, I agree that printing a stack trace for functional errors that are supposed to happen sometimes (for example: OAS file not found or invalid) is annoying for users.

But this one belongs to the class of errors that are never supposed to happen, and typically indicate an internal bug. I think they should always be printed with rich info, possibly asking to create an issue. Exceptions like NullReferenceException, TypeLoadException, DivideByZeroException, InvalidCastException, IndexOutOfRangeException, OverflowException etc. May also include FormatException and ArgumentException, depending on whether they could happen under normal circumstances.

[andrueastman]

There's a chance this could be related to microsoft/OpenAPI.NET#1202. So, once we resolve #5936 and pull in a version with NRT information this may be resolved.