# Version Checker - Container Image Version Monitoring for Kubernetes
# Namespace: version-checker-system
# 
# This deploys jetstack/version-checker which monitors all container images
# running in the cluster and compares them to latest available upstream versions.
# Metrics are exposed for Prometheus scraping.
#
# Documentation: https://github.com/jetstack/version-checker
#
# Metrics exposed:
# - version_checker_is_latest_version{...} = 1 (up to date) or 0 (outdated)
# - version_checker_image_info{image, current_version, latest_version, ...}
---
apiVersion: v1
kind: Namespace
metadata:
  name: version-checker-system
  labels:
    app.kubernetes.io/name: version-checker
---
apiVersion: v1
kind: ServiceAccount
metadata:
  name: version-checker
  namespace: version-checker-system
  labels:
    app.kubernetes.io/name: version-checker
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  name: version-checker
  labels:
    app.kubernetes.io/name: version-checker
rules:
  # Required to read pod specs to get container images
  - apiGroups: [""]
    resources: ["pods"]
    verbs: ["get", "watch", "list"]
  # Required to check Kubernetes version (optional feature)
  - apiGroups: [""]
    resources: ["nodes"]
    verbs: ["get", "list"]
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: version-checker
  labels:
    app.kubernetes.io/name: version-checker
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: version-checker
subjects:
  - kind: ServiceAccount
    name: version-checker
    namespace: version-checker-system
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: version-checker
  namespace: version-checker-system
  labels:
    app.kubernetes.io/name: version-checker
    app.kubernetes.io/instance: version-checker
    app.kubernetes.io/version: "v0.10.0"
  annotations:
    reloader.stakater.com/auto: "true"
spec:
  replicas: 1
  selector:
    matchLabels:
      app.kubernetes.io/name: version-checker
      app.kubernetes.io/instance: version-checker
  template:
    metadata:
      labels:
        app.kubernetes.io/name: version-checker
        app.kubernetes.io/instance: version-checker
        app.kubernetes.io/version: "v0.10.0"
      annotations:
        prometheus.io/scrape: "true"
        prometheus.io/port: "8080"
        prometheus.io/path: "/metrics"
    spec:
      serviceAccountName: version-checker
      securityContext:
        runAsNonRoot: true
        runAsUser: 1000
        fsGroup: 1000
      containers:
        - name: version-checker
          image: quay.io/jetstack/version-checker:v0.10.0
          imagePullPolicy: IfNotPresent
          args:
            # Test ALL containers in the cluster (not just annotated ones)
            - --test-all-containers
            # How often to re-check versions (default: 1h)
            - --image-cache-timeout=1h
            # Log level
            - --log-level=info
          ports:
            - name: metrics
              containerPort: 8080
              protocol: TCP
          resources:
            requests:
              cpu: 10m
              memory: 32Mi
            limits:
              cpu: 100m
              memory: 128Mi
          livenessProbe:
            httpGet:
              path: /healthz
              port: metrics
            initialDelaySeconds: 30
            periodSeconds: 30
          readinessProbe:
            httpGet:
              path: /readyz
              port: metrics
            initialDelaySeconds: 10
            periodSeconds: 10
          securityContext:
            allowPrivilegeEscalation: false
            readOnlyRootFilesystem: true
            capabilities:
              drop:
                - ALL
---
apiVersion: v1
kind: Service
metadata:
  name: version-checker
  namespace: version-checker-system
  labels:
    app.kubernetes.io/name: version-checker
    app.kubernetes.io/instance: version-checker
spec:
  type: ClusterIP
  ports:
    - name: metrics
      port: 8080
      targetPort: metrics
      protocol: TCP
  selector:
    app.kubernetes.io/name: version-checker
    app.kubernetes.io/instance: version-checker
---
# ServiceMonitor for Prometheus Operator (if using kube-prometheus-stack)
# If you're using plain Prometheus with pod annotations, this can be removed
# apiVersion: monitoring.coreos.com/v1
# kind: ServiceMonitor
# metadata:
#   name: version-checker
#   namespace: version-checker-system
#   labels:
#     app.kubernetes.io/name: version-checker
#     app.kubernetes.io/instance: version-checker
#     # Add your Prometheus selector label if needed
#     # release: prometheus
# spec:
#   selector:
#     matchLabels:
#       app.kubernetes.io/name: version-checker
#   namespaceSelector:
#     matchNames:
#       - version-checker-system
#   endpoints:
#     - port: metrics
#       interval: 5m
#       scrapeTimeout: 30s
#       path: /metrics