feat: add fairwinds polaris

Dockerfile

@@ -12,6 +12,7 @@ ARG YQ_VERSION
 ARG HELM_VERSION
 ARG KUSTOMIZE_VERSION
 ARG KUBECONFORM_VERSION
+ARG POLARIS_VERSION
 
 # renovate: datasource=github-releases depName=kubernetes/kubernetes
 ENV KUBECTL_VERSION="${KUBECTL_VERSION:-v1.27.3}"
@@ -23,6 +24,8 @@ ENV HELM_VERSION="${HELM_VERSION:-v3.12.1}"
 ENV KUSTOMIZE_VERSION="${KUSTOMIZE_VERSION:-v5.1.0}"
 # renovate: datasource=github-releases depName=yannh/kubeconform
 ENV KUBECONFORM_VERSION="${KUBECONFORM_VERSION:-v0.6.2}"
+# renovate: datasource=github-releases depName=FairwindsOps/polaris
+ENV POLARIS_VERSION="${POLARIS_VERSION:-8.2.3}"
 
 RUN apk --update add curl tar bash python3 py3-yaml && \
     curl -SsfL -o /usr/local/bin/kubectl "https://dl.k8s.io/release/${KUBECTL_VERSION}/bin/linux/amd64/kubectl" && \
@@ -34,6 +37,8 @@ RUN apk --update add curl tar bash python3 py3-yaml && \
         | tar xz -C /usr/local/bin kustomize && \
     curl -SsfL "https://github.com/yannh/kubeconform/releases/download/${KUBECONFORM_VERSION}/kubeconform-linux-amd64.tar.gz" \
         | tar xz -C /usr/local/bin kubeconform && \
+    curl -SsfL "https://github.com/FairwindsOps/polaris/releases/download/${POLARIS_VERSION}/polaris_linux_amd64.tar.gz" \
+        | tar xz -C /usr/local/bin polaris && \
     chmod 755 /usr/local/bin/kubectl && \
     chmod 755 /usr/local/bin/kubectl-convert && \
     chmod 755 /usr/local/bin/yq && \

overlay/usr/local/bin/flux-audit

@@ -0,0 +1,40 @@
+#!/usr/bin/env bash
+set -eo pipefail
+
+KUSTOMIZE_FLAGS=("--load-restrictor=LoadRestrictionsNone")
+KUSTOMIZE_CONFIG="kustomization.yaml"
+
+FLUX_PATH="${1:-.}"
+POLARIS_EXCLUDE_PATHS=(
+    "flux/clusters/cloud-infra/flux-system/"
+)
+
+if [ -z "$POLARIS_CONFIG" ]; then
+    POLARIS_CONFIG=(
+        "--format=pretty"
+        "--set-exit-code-on-danger"
+        "--set-exit-code-below-score=80"
+        "--only-show-failed-tests=true"
+        "--audit-path=-"
+    )
+else
+    # shellcheck disable=SC2128
+    IFS=', ' read -r -a POLARIS_CONFIG <<<"$POLARIS_CONFIG"
+fi
+
+printf "\nINFO - Auditing kustomize overlays\n"
+find "${FLUX_PATH%/}" -type f -name $KUSTOMIZE_CONFIG -print0 | while IFS= read -r -d $'\0' file; do
+    printf "INFO - Auditing kustomization %s\n" "${file/%$KUSTOMIZE_CONFIG/}"
+    for EXCLUDE in "${POLARIS_EXCLUDE_PATHS[@]}"; do
+        if [ "$EXCLUDE" == "${file/%$KUSTOMIZE_CONFIG/}" ]; then
+            continue 2
+        fi
+    done
+
+    kustomize build "${file/%$KUSTOMIZE_CONFIG/}" "${KUSTOMIZE_FLAGS[@]}" |
+        polaris audit "${POLARIS_CONFIG[@]}"
+    echo
+    if [[ ${PIPESTATUS[0]} != 0 ]]; then
+        exit 1
+    fi
+done