UPSTREAM: <carry>: do not set the generation for cached object

[p0lyn0mial]

This PR allows:

• for setting a generation during object creation so that it matches the original object
• for setting a generation during an update so that it matches the original one

Essentially, the generation field for cached objects won't be managed by the generic/extensions API server.

part of kcp-dev/kcp#342

[ncdc]

I don't believe you need to get/set the map. You should be able to delete directly. https://go.dev/play/p/r7Wr8PbmwN9. Hopefully meta.Accessor doesn't change that?

[p0lyn0mial]

ah, right, recently I have worked with an unstructured object that gave me a copy, here indeed we get a pointer.

[sttts]

idiomatic: _, found := accessor.GetAnnotations()[genericapirequest.AnnotationKey]; found

[ncdc]

Funny, I told Joaquim to just do if annotations[key] != "" the other day. I'd call this one personal preference maybe.

[p0lyn0mial]

if the language was more strict we wouldn't have to discuss at least 3 different ways of reading a value from a map :)

[sttts]

don't think this is correct (have seen the old thread). GetAnnotations() returns a map[string]string. In unstructured, it is map[string]interface{}. Hence, there must be a deepcopy with type cast happening.

[sttts]

To avoid the deepcopy use the *NoCopy unstructured helpers.

[p0lyn0mial]

brought back the previous version, I don't think we need to use NoCopy. Using GetAnnotaions/SetAnnotations is always correct.

[p0lyn0mial]

serverResource uses unstructuredCreator, that means requests to that EP will operate on unstructured data

kubernetes/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/customresource_handler.go

Line 871 in 3ddc03b

creator := unstructuredCreator{}

[p0lyn0mial]

I think that comparing to an empty string is more readable but I can change to _, found := accessor.GetAnnotations()[genericapirequest.AnnotationKey]; !found

[sttts]

/lgtm
/approve