Automatic merge from submit-queue (batch tested with PRs 46801, 45184, 45930, 46192, 45563)
Tweak client-gen to support metrics API
This PR adds support to client-gen for readonly APIs as well as for customizing the resource name used for a given type.
This is required to support the clients generated for `k8s.io/metrics/pkg/apis/metrics`.
cc @caesarxuchao
Currently based on #45180
**Release note**:
```release-note
NONE
```
This commit adds support for read-only APIs to client-gen.
If the tag `// +readonly=true` is used, only the {Get,List,Watch}
client methods will be generated.
This commit allows client-gen to generate clients where the resource
name does not directly correspond to the type name.
The tag `// +resourceName=<name>` can be used to override the resource
name.
This means that tags like:
// +foo=bar
// +foo=bat
..will produce []string{"bar", "bat"}. This is needed for later commits which
will want to use this to make code generation more self contained.
Fake clientset is used by unit tests extensively but it has some
shortcomings:
- no filtering on namespace and name: tests that want to test objects in
multiple namespaces end up getting all objects from this clientset,
as it doesn't perform any filtering based on name and namespace;
- updates and deletes don't modify the clientset state, so some tests
can get unexpected results if they modify/delete objects using the
clientset;
- it's possible to insert multiple objects with the same
kind/name/namespace, this leads to confusing behavior, as retrieval is
based on the insertion order, but anchors on the last added object as
long as no more objects are added.
This change changes core.ObjectRetriever implementation to track object
adds, updates and deletes.
Some unit tests were depending on the previous (and somewhat incorrect)
behavior. These are fixed in the following few commits.
