Upgrade to Kubebuilder v2

[anyasabo]

Summary

Related to #1188 and #1604

• Migrate to kubebuilder v2 API layout -- essentially the boilerplate is contained to groupversion_info.go rather than spread out over multiple files.
• Upgrade to golang v1.13
• Disables check-fmt during CI since controller-gen generates deepcopy files that do not match some newer versions, and enforcing it as part of CI is discouraged by the go team. I'll open a PR to fix it in controller-tools.
• Removes the webhook server. It will be reintroduced in a future PR once we nail down details
• Adds InjectMapper() to DynamicEnqueueRequest because it was introduced upstream in https://github.com/kubernetes-sigs/controller-runtime/pull/274/files
• Removes outdated controller-gen markers and updates to current markers (see docs). This is primarily +genclient, +k8s:openapi-gen=true, and +k8s:deepcopy-gen
• The k8s client CRUD options were refactored to take ...ListOptions etc, which required...a bit of refactoring in our calls rather than passing around a Selector everywhere. There were also some tests that were passing that should have been failing (and are now failing) because selectors were not applied to fake clients in the past.
• Revs golangci-lint to 1.18 to support golang 1.13 -- also disables funlen because that throws a lot of errors that we can fix later if we want
• Disables local changes as part of CI check. It was warning about go.mod modifications, even though if I run make ci locally nothing modifies my gomod files.
• Adds CI test output files to gitignore

Differences from stock kubebuilder v2

• Not using distroless
• Not exposing election command line opts
• There are now controller builders in controller-runtime to make the watches a little bit easier to set up. For our basic use cases it may be worth migrating to be more idiomatic.
• Normally there's not a cmd pkg, but since we parse a lot of command line opts this is idiomatic for cobra

Outstanding tasks

• Update CI to work with go modules
• Update manifest generation -- see run/install/deploy/manifests make targets in new kubebuilder defaults vs our generate-crds and generate-all-in-one
• Decide how we rework webhook functionality
  • Fix outstanding license validation todo
• Add new rbac markers. Example here
• Re-enable API reference documentation. Once we tag a release of our fork this can be started.

Notes

To compare to a base project I like to start up a new project to see how they scaffold it out

kubebuilder init --domain tutorial.kubebuilder.io
kubebuilder create api --group batch --version v1 --kind CronJob

Migration guide: https://book.kubebuilder.io/migration/guide.html
Marker docs: https://book.kubebuilder.io/reference/markers.html

[pebrc]

I'd generally be in favor of merging this quickly

👍 I think so too

[thbkrkr]

LGTM!
Left some nits and questions but nothing to prevent a merge.

[anyasabo]

Created follow up issues for all the ones I know about, I'm sure we'll find more

[sebgl]

🚀

[pebrc]

LGTM!

[pebrc]

Any particular reason these need to be exported?

[anyasabo]

I meant to leave a comment about that or fix it -- that was part of the change to using the new controller builder funcs that I later rolled back. Now there's not a good reason so I'll switch it back.

[anyasabo]

Jenkins test this please