Fetch go version using gimme if needed

[liggitt]

What type of PR is this?

/kind feature

What this PR does / why we need it:

Allows kube::golang::verify_go_version to choose a go version. Defaults to .go-version, can be overridden by GO_VERSION=1.x or skipped entirely with FORCE_HOST_GO=y

Copies approach taken by https://github.com/kubernetes-sigs/kind/blob/main/hack/build/setup-go.sh

xref kubernetes/test-infra#28310

Special notes for your reviewer:

Does this PR introduce a user-facing change?

The go version defined in `.go-version` is now fetched when invoking test, build, and code generation targets if the current go version does not match it. Set $FORCE_HOST_GO=y while testing or building to skip this behavior, or set $GO_VERSION to override the selected go version.

/cc @dims @BenTheElder

[dims]

definitely makes things easier. we should probably not get in the way of the local dev env as well (only warn them?) also not install something unless they explicitly ok us installing something in their env?

[liggitt]

also not install something unless they explicitly ok us installing something in their env?

that's my instinct as well... could make our CI jobs opt into this behavior, and indicate how to opt-into auto-version-setup in verify_go_version if people want it

[liggitt]

awesome, consistently using go1.20rc3 for all our non-e2e presubmits caught an issue in verify-typecheck running with go1.20rc3 that #114502 missed:

ERROR(linux/ppc64le): /home/prow/go/src/k8s.io/kubernetes/_output/local/.gimme/versions/go1.20rc3.linux.amd64/src/os/user/cgo_lookup_unix.go:169:22: invalid argument: index startSize (variable of type bufferKind) must be integer

we already exclude some cgo things in the typecheck because the go type scanner can't reliably interpret it... added a commit to exclude error checking of stdlib packages, will open in a separate PR to merge ahead of #114502

[BenTheElder]

I think we should consider opt-out.

If you want a custom go toolchain you already need to override any of the dockerized bits.

opt-out gives a smoother more reproducible developer experience for the 99% case.

KIND has opt-out + it will just use the existing toolchain if the version is correct.

[BenTheElder]

I think the tricky part in k/k is aligning these knobs with the dockerized build bits.
IIRC kind builds are fully using dockerized but some other CI may be mixed.

[liggitt]

interesting... by changing nothing other than the .go-version, this was able to build with go1.20rc3 even in the e2e:

I0129 05:08:21.171] Server Version: version.Info{Major:"1", Minor:"27+", GitVersion:"v1.27.0-alpha.1.79+87116b4ea03d66", GitCommit:"87116b4ea03d66a1723a16c6571931edf73d8b5f", GitTreeState:"clean", BuildDate:"2023-01-28T18:20:43Z", GoVersion:"go1.20rc3", Compiler:"gc", Platform:"linux/amd64"}

that's ... kind of awesome

[dims]

very cool @liggitt !

[k8s-ci-robot]

LGTM label has been added.

Git tree hash: 08c4d15a33357bce71f6de844c3d4cf3df04cf81

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: dims, liggitt

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• LICENSES/OWNERS [dims,liggitt]
• build/OWNERS [dims,liggitt]
• hack/OWNERS [dims,liggitt]
• third_party/OWNERS [dims,liggitt]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[liggitt]

/hold cancel

[BenTheElder]

belated
/lgtm
/approve
very happy to see this!