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
```
Automatic merge from submit-queue
let client-gen understand vendor
This is extracted from #44784, where we move external api types to k8s.io/api. After the move, the types will locate at vendor/k8s.io/api/xxx. However, gengo index the parsed package using the import path, which is stripped of the vendor/ prefix, so we'll need to strip the vendor/ prefix as necessary in client-gen.
This PR doesn't produce any change to the generated clientset yet since all types are still in the kubernetes repo.
If there is a comment of the form "// +groupName=somegroup" or
"// +groupName=somegroup.foo.bar.io", use the first field (somegroup) as
the name of the group in customArgs.GroupVersions and
customArgs.GroupVersionToInputPath.
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.
