validate-k8s-change

name	validate-k8s-change
description	Validate Kubernetes changes before commit by auto-detecting changed kustomizations and Helm values/charts, then running kustomize build and helm template/lint with a pass/fail report. Use for pre-commit checks, PR prep, and GitOps safety checks.
argument-hint	Optional scope: staged (default), all, or a path prefix like kubernetes/helm/external-dns

Validate Kubernetes Change

Run one command workflow that inspects changed files and validates only impacted Kubernetes targets.

When To Use

• Before commit for changes under kubernetes/, charts/, or app-of-apps templates.
• Before opening a PR that modifies Helm values, charts, or kustomizations.
• After rebasing when change scope may have shifted.

Inputs

• Optional argument:
• staged: validate staged files only (default)
• all: validate all working-tree changes vs HEAD
• : validate only changes under that prefix

Procedure

1. Discover changed files.

• Use staged scope by default: git diff --name-only --cached
• If argument is all: git diff --name-only HEAD
• If argument is a path prefix, filter to that prefix.
• If no files match kubernetes/, charts/, or app-of-apps templates, stop with a no-op message.

2. Resolve impacted kustomize targets.

• Find unique directories matching kubernetes/kustomizations// from changed files.
• Keep only directories that contain kustomization.yaml.
• Validate each target with:
• kustomize build kubernetes/kustomizations/

3. Resolve impacted Helm targets from changed values files.

• For each changed file under kubernetes/helm//, locate matching app-of-apps template references in kubernetes/bootstrap/charts/app-of-apps/templates/.
• Support these source styles:
• chart + repoURL: helm template --repo -f
• OCI repoURL with path ".": helm template -f
• Local path charts/: helm lint charts/ and helm template charts/ -f
• If multiple valueFiles are defined for one app (for example external-dns), validate each changed values file and also run one combined render when both files are changed.

4. Resolve impacted Helm chart targets from local chart edits.

• For each changed path under charts//:
• helm lint charts/
• If kubernetes/helm//values.yaml exists, also run:
• helm template charts/ -f kubernetes/helm//values.yaml

5. Track results and continue on failure.

• Run all discovered validations and collect pass/fail per command.
• Do not stop at the first failure; finish the full impacted set.

6. Report concise outcome.

• Print a summary table with: target, command, status, key error line.
• Exit with failure if any validation failed.
• Include next actions that are specific (for example fix schema/key mismatch in values file, or invalid field in rendered manifest).

Required Guardrails

• Never edit sync-waves-inventory.md directly.
• For kustomize apps, check kustomization.yaml for patches/transformers/images before assuming base manifest edits are sufficient.
• Keep temporary artifacts under .tmp/ if files are needed.

Quick Command Pattern

Use this shell pattern during execution to gather candidates quickly:

changed_files() {
  case "$1" in
    all) git diff --name-only HEAD ;;
    "") git diff --name-only --cached ;;
    *) git diff --name-only --cached | rg "^$1" || true ;;
  esac
}

Then derive targets with rg/cut/sort -u and run kustomize/helm validations on the resulting unique sets.