Change references of googleapis/gnostic -> google/gnostic

[Jefftree]

See kubernetes/kubernetes#108644

k/k and k/kube-openapi need to change googleapis/gnostic -> google/gnostic at the same time to avoid type check failure.

Test failure: https://prow.k8s.io/view/gs/kubernetes-jenkins/pr-logs/pull/108644/pull-kubernetes-integration/1502033895208521728

Change references of googleapis/gnostic -> google/gnostic

Also upgrade gnostic from 0.5.5 to 0.6.6. No significant changes for openapi_v2 and openapi_v3,

• https://github.com/google/gnostic/commits/master/openapiv2
• https://github.com/google/gnostic/commits/master/openapiv3

since April 26, 2021 @ version v0.5.5

• PR 250 updates the .md file
• PR 259 Renames googleapis -> google
• PR 270 updates the protoc version

/assign @apelisse

[apelisse]

OK Thanks,
/lgtm
/approve

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[mattrobenolt]

I think this breaks dependencies like k8s.io/client-go too.

I'm not entirely sure, since this is a bit over my head in how Go resolves dependencies.

But it seems that because the old version googleapis/gnostic is just a redirect to the newer version google/gnostic, I think explicitly in the dependency resolver, it doesn't treat them the same.

So what's happening is I'm getting an indirect dependency for both google/gnostic v0.6.6 and googleapis/gnostic v0.5.5 from client-go. I think this confuses the compiler or somewhere in that it tries to alias the googleapis/gnostic version as google/gnostic and they are incompatible because different versions? I'm not exactly sure.

But the exact compilation error when updating deps now is:

/go/pkg/mod/k8s.io/[email protected]/applyconfigurations/meta/v1/unstructured.go:64:38: cannot use doc (variable of type *"github.com/googleapis/gnostic/openapiv2".Document) as *"github.com/google/gnostic/openapiv2".Document value in argument to proto.NewOpenAPIData (compile)

I'm not exactly sure how to work around this or what the resolution is.

[mattrobenolt]

I guess I worked around it by pinning my indirect dependency to a sha before this one, and it resolved it.

I wasn't able to reproduce it on a new project either, so I'm not sure the perfect storm that leads to this being a problem.

[Jefftree]

@mattrobenolt Yes, we are aware there will be a version mismatch with kubernetes/kubernetes (and subsequently the client-go applyconfigurations) until kubernetes/kubernetes#108644 is merged.

[liggitt]

I think this breaks dependencies like k8s.io/client-go too.

it shouldn't, as long as you use the level of kube-openapi referenced by client-go. did you run go get -u to bump all dependencies to their latest versions? client-go has many v0.x.y dependencies that will not work with