Use node status.addresses for kubelet health-check

[kwohlfahrt]

Why we need this PR

To support clusters where the node's name is not resolvable, but the addresses in status.addresses can be used instead.

Changes made

• Add a new config options (preferredAddressTypes) that allows selecting addresses from status.addresses (and a special NodeName value, for the old behaviour, on by default)
• Get node addresses on startup from the node's status.addresses, use the enabled ones when trying the kubelet health-check
• Small tweak to Makefile to download the correct protoc on aarch64 dev machines

Which issue(s) this PR fixes

Closes #330.

Test plan

Added new unit tests for control-plane manager kubelet liveness checks, and new e2e tests for daemonset rendering.

[openshift-ci]

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[openshift-ci]

Hi @kwohlfahrt. Thanks for your PR.

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[coderabbitai]

📝 Walkthrough

Summary by CodeRabbit

• New Features

  • Added configurable node address preferences for kubelet health checks.
  • Supports NodeName, hostname, DNS, and IP address types, with fallback ordering.
  • Preserves NodeName behavior when no preference is configured.
  • Added support for architecture-specific protoc downloads on ARM64 systems.

• Bug Fixes

  • Kubelet checks now try multiple configured addresses and provide clearer connection errors.

Walkthrough

Changes

Kubelet address selection

Layer / File(s)	Summary
Address configuration and DaemonSet wiring api/v1alpha1/..., config/crd/..., bundle/manifests/..., internal/controller/..., install/...	Adds optional PreferredAddressTypes configuration, CRD validation, deepcopy support, and PREFERRED_ADDRESS_TYPES DaemonSet wiring.
Ordered kubelet address checks internal/controlplane/...	Parses configured address types, stores node addresses, and checks kubelet endpoints in preference order with fallback behavior covered by tests.

Architecture-aware protoc download

Layer / File(s)	Summary
Architecture-specific protoc download Makefile	Maps GOARCH values to protoc archive architectures and uses the mapped value for downloads.

Estimated code review effort: 3 (Moderate) | ~20 minutes

Suggested reviewers: slintes, mshitrit

Sequence Diagram(s)

sequenceDiagram
  participant SelfNodeRemediationConfig
  participant Controller
  participant DaemonSet
  participant Manager
  participant KubernetesNode
  participant Kubelet

  SelfNodeRemediationConfig->>Controller: Set PreferredAddressTypes
  Controller->>DaemonSet: Render PREFERRED_ADDRESS_TYPES
  DaemonSet->>Manager: Provide environment configuration
  Manager->>KubernetesNode: Read status.addresses
  Manager->>Kubelet: Try preferred addresses in order
  Kubelet-->>Manager: Return health response

Loading

🚥 Pre-merge checks | ✅ 3 | ❌ 2

❌ Failed checks (2 warnings)

Check name	Status	Explanation	Resolution
Out of Scope Changes check	⚠️ Warning	The Makefile change for downloading aarch64 protoc is unrelated to the linked kubelet address objective [#330].	Move the aarch64 protoc download change to a separate pull request, or link it to an issue that requires this build improvement.
Docstring Coverage	⚠️ Warning	Docstring coverage is 33.33% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (3 passed)

Check name	Status	Explanation
Linked Issues check	✅ Passed	The changes implement ordered kubelet address selection, preserve NodeName behavior by default, and add tests for the requested scenarios [#330].
Title check	✅ Passed	The title clearly identifies the main change: using node status addresses for kubelet health checks.
Description check	✅ Passed	The description explains configurable address selection, fallback behavior, tests, and the related Makefile change.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[coderabbitai]

Actionable comments posted: 2

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@internal/controlplane/manager.go`:
- Around line 184-205: Update isKubeletServiceRunningOnAddress to build the
kubelet endpoint with net.JoinHostPort(address, manager.kubeletPort) before
constructing the HTTPS URL, preserving valid formatting for both IPv4 and IPv6
addresses. Add a test using an IPv6 loopback listener to verify the address is
contacted successfully.

In `@Makefile`:
- Around line 409-412: Update the PROTOC_ARCH mapping to translate GOARCH values
ppc64le, s390x, and 386 to ppcle_64, s390_64, and x86_32 respectively, or make
the Makefile fail early with a clear unsupported-architecture error for unmapped
values before the protoc download runs.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: 8eb1c779-5525-4ec1-a7d2-a6cdc73857ea

📥 Commits

Reviewing files that changed from the base of the PR and between 08359bb and 93555dc.

📒 Files selected for processing (11)

• Makefile
• api/v1alpha1/selfnoderemediationconfig_types.go
• api/v1alpha1/zz_generated.deepcopy.go
• bundle/manifests/self-node-remediation.medik8s.io_selfnoderemediationconfigs.yaml
• config/crd/bases/self-node-remediation.medik8s.io_selfnoderemediationconfigs.yaml
• install/self-node-remediation-deamonset.yaml
• internal/controller/selfnoderemediationconfig_controller.go
• internal/controller/tests/config/selfnoderemediationconfig_controller_test.go
• internal/controlplane/manager.go
• internal/controlplane/manager_test.go
• internal/controlplane/suite_test.go