cert-manager: add feature gate options for webhook and cainjector

[KR-Ravindra]

What this PR does / why we need it:

Adds webhookFeatureGates and cainjectorFeatureGates to spec.certManager, so cert-manager feature gates can be set per component instead of only on the controller.

Problem

spec.certManager.featureGates is only rendered into the args of the cert-manager-controller container. The webhook and cainjector Deployments never receive --feature-gates, so gates that cert-manager documents as needing both the controller and the webhook (for example AdditionalCertificateOutputFormats or NameConstraints) are only half-applied: the controller supports the feature while the webhook refuses the resources that use it.

Root cause

upup/models/cloudup/resources/addons/certmanager.io/k8s-1.16.yaml.template:

• line 13347: {{ range $key, $value := .CertManager.FeatureGates }} emits --feature-gates for the controller only
• line 13448: the cert-manager-webhook container args have no feature gate handling
• line 13248: the cert-manager-cainjector container args have no feature gate handling

The three cert-manager components accept different sets of gates (see the cert-manager feature-gates documentation, linked from docs/addons.md in this PR), so blindly copying featureGates to every container would not be correct either. The cert-manager Helm chart solves this with per-component values (featureGates, webhook.featureGates, cainjector.featureGates), which is the approach suggested in the issue discussion.

Fix

• CertManagerConfig gains WebhookFeatureGates and CAInjectorFeatureGates (map[string]bool) in pkg/apis/kops, v1alpha2 and v1alpha3; conversion and deepcopy regenerated with make apimachinery-codegen, CRD regenerated with make crds.
• The addon template renders the new maps into the webhook and cainjector container args, using the same range pattern as the controller. featureGates keeps applying to the controller only, so existing clusters are unchanged.
• docs/addons.md documents the per-component gates.
• The many-addons integration fixture sets both new fields and the golden output was regenerated with hack/update-expected.sh.

How tested

Golden update-cluster test (TestManyAddons), no cloud account needed.

Before the template change, with the fixture setting webhookFeatureGates / cainjectorFeatureGates and the expected webhook and cainjector args written into the golden file:

--- FAIL: TestManyAddons (0.49s)
    compare.go:81: diff:
        ...
                  - --v=2
                  - --leader-election-namespace=kube-system
        -         - --feature-gates=ServerSideApply=true
                  env:
                  - name: POD_NAMESPACE
        ...
                  - --dynamic-serving-dns-names=cert-manager-webhook.$(POD_NAMESPACE)
                  - --dynamic-serving-dns-names=cert-manager-webhook.$(POD_NAMESPACE).svc
        -         - --feature-gates=AdditionalCertificateOutputFormats=true
                  env:
        ...
    compare.go:85: output did not match expected for ".../many-addons/data/aws_s3_object_many-addons.example.com-addons-certmanager.io-k8s-1.16_content"
FAIL

After the template change:

=== RUN   TestManyAddons
--- PASS: TestManyAddons (0.46s)
PASS
ok  	k8s.io/kops/cmd/kops	0.519s

hack/update-expected.sh ./cmd/kops/ afterwards produced no further changes beyond the many-addons fixture (certmanager.io manifest, its manifestHash in the bootstrap addon list, and cluster-completed.spec). Also ran make apimachinery-codegen (no diff), go test ./pkg/apis/kops/..., go vet and go build ./cmd/kops/.

Links

• cert-manager: feature gates are not applied to webhook #17797

Which issue(s) this PR fixes:

Fixes #17797

Special notes for your reviewer:

The kops_feature_table entry in the docs says 1.37; adjust if this lands in a different release. Gate names in the fixture (AdditionalCertificateOutputFormats for the webhook, ServerSideApply for the cainjector) are taken from cert-manager's webhook and cainjector feature lists.

This change was prepared with an AI agent operated by KR-Ravindra, who reviewed and tested it.

[kubernetes-prow]

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[kubernetes-prow]

Hi @KR-Ravindra. Thanks for your PR.

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[KR-Ravindra]

Round 1 self-review.

Re-checked against master: the two new maps are wired through kops, v1alpha2 and v1alpha3 with regenerated deepcopy, conversion and CRD, and the template uses the same range pattern as the existing controller featureGates, so flag ordering is deterministic and clusters that leave the fields unset render identically (only the many-addons fixture changes, by the two expected --feature-gates lines). This follows the per-component approach discussed in #17797 rather than copying the controller gates to every container, since the three components accept different gate sets.

The docs table says 1.37, matching KOPS_RELEASE_VERSION on master today; if this should land as 1.38 because release-1.37 is already cut, I will change it.

Marking ready for review.

[hakman]

/ok-to-test

[KR-Ravindra]

/retest

The gce-cilium failure was a sum.golang.org stream error while ko verified a module during the kops-controller image build, before any cluster was created.

[hakman]

/retest

[KR-Ravindra]

The second pull-kops-e2e-k8s-gce-ipalias run failed the same way as the first: sum.golang.org/tile/8/0/x141/455: stream error while ko verified go-jose/v4 during the kops-controller image build, before any cluster was created. Job history shows the same job green on 13 of the last 20 runs, so retrying once more.

/test pull-kops-e2e-k8s-gce-ipalias

[KR-Ravindra]

/test pull-kops-e2e-k8s-gce-cilium

[hakman]

Thanks for this @KR-Ravindra (and your AI).
/lgtm
/approve

[kubernetes-prow]

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