Unable to conversion-gen conversions that require a conversion.Scope

[ncdc]

Some functions autogenerated by conversion-gen produce code that looks like this:

func autoConvert_v1alpha1_Something_To_v1alpha2_Something(in *Something, out *v1alpha2.Something, s conversion.Scope) error {
  // normal convertible fields
  out.X = in.X
  // TODO: Inefficient conversion - can we improve it?
  if err := s.Convert(&in.SomeField, &out.SomeField, 0); err != nil {
    return err
  }
  return nil
}

The "inefficient conversion" can happen in a few different situations; in this case, it's because SomeField is a struct that lives in a package outside of the one where I'm generating conversions. Due to kubernetes/code-generator#94 (assuming there isn't a workaround), even if there were conversion functions for SomeField, conversion-gen isn't able to see & use them.

We presumably need access to a conversion.Scope in our ConvertTo/ConvertFrom implementations, but these are member functions on the types, and I haven't yet found any way to get access to a Scope (this appears to have a single, unexported implementation that is used internally by the conversion machinery code).

Anyone know of a way to use generated conversion functions that need a Scope?

[vincepri]

/priority awaiting-more-evidence
/help

[k8s-ci-robot]

@vincepri:
This request has been marked as needing help from a contributor.

Please ensure the request meets the requirements listed here.

If this request no longer meets these requirements, the label can be removed
by commenting with the /remove-help command.

In response to this:

/priority awaiting-more-evidence
/help

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[fejta-bot]

Issues go stale after 90d of inactivity.
Mark the issue as fresh with /remove-lifecycle stale.
Stale issues rot after an additional 30d of inactivity and eventually close.

If this issue is safe to close now please do so with /close.

Send feedback to sig-testing, kubernetes/test-infra and/or fejta.
/lifecycle stale

[fejta-bot]

Stale issues rot after 30d of inactivity.
Mark the issue as fresh with /remove-lifecycle rotten.
Rotten issues close after an additional 30d of inactivity.

If this issue is safe to close now please do so with /close.

Send feedback to sig-testing, kubernetes/test-infra and/or fejta.
/lifecycle rotten

[vincepri]

/lifecycle frozen

[ANeumann82]

I ran into the same issue - conversion-gen is great to generate the default conversions between api versions, and controller-runtime is great for providing an easy setup for a conversion webhook, but I don't see a way to connect both nicely together. the conversion.Scope is required for the generated code.