An openapi "client" is failing to decode json-pointer-encoded strings

[ericpromislow]

A user of an extension for Rancher was reporting that it was showing in the Rancher UI as installed, but wasn't returning
any output. Rancher uses a module called steve as a shim between the UI and a kubernetes server.

During startup. after I installed the component, I saw that steve was failing to load all the schemas, specifically with the error message

SchemaError(github.com/kubewarden/sbomscanner/api/storage/v1alpha1.ContainerRef.imageRef):
   unknown model in reference: "github.com~1kubewarden~1sbomscanner~1api~1storage~1v1alpha1.ImageRef"

There is a model for github.com/kubewarden/sbomscanner/api/storage/v1alpha1.ContainerRef.imageRef in the definitions section of the openapi/v2 doc that this code uses, but not one with the tildes.

Today I learned about json-pointer, which makes sense. Otherwise a ref string like "definitions/github.com/kubewarden/sbomscanner/api/storage/v1alpha1.ContainerRef.imageRef" would be ambiguous: is it pointing first at the top-level definitions section, then a sub-section called "github.com", etc.?

Openapi/v2 clients deal with this by decoding these reference strings, converting instances of ~1 to / and ~0 to ~.

The code at

kube-openapi/pkg/util/proto/document.go

Lines 108 to 111 in 5b3e3fd

	reference := strings.TrimPrefix(s.GetXRef(), "#/definitions/")
	if _, ok := d.models[reference]; !ok {
	return nil, newSchemaError(path, "unknown model in reference: %q", reference)
	}

isn't doing that -- it's taking reference strings and trying to use them immediately as keys into the definitions section.

PR coming up...

[Jefftree]

How is the openapi for that generated? For all our provided generators, we explicitly escape the name so that no slashes are present (https://github.com/kubernetes/kube-openapi/blob/master/pkg/util/util.go#L58). The issue is valid but I feel like most of our tooling is not designed around it.

[ingvagabund]

@ericpromislow looks like #580 I reported is describing the same? I have opened a PR at #585.