K8s Manifest Diff

Render manifests, diff against cluster or git, flag risks. Read-only.

1. Prerequisites

• command -v kubectl -- REQUIRED. Abort immediately if missing.
• helm, kustomize -- optional, detected from input. kubectl kustomize as fallback.
• If --context in $ARGUMENTS, pass --context <value> to all kubectl calls.
• Run kubectl cluster-info to test access. If unreachable, set CLUSTER_AVAILABLE=false and continue (git-based diff still works). Print kubectl config current-context if available.
• Fail fast only if kubectl binary is missing.

2. Detection

Determine type from input path in $ARGUMENTS:

• Chart.yaml in directory --> Helm (helm template).
• kustomization.yaml/kustomization.yml --> Kustomize (kubectl kustomize).
• Plain .yaml/.yml --> raw YAML (cat). Single file always uses raw mode.