Add version-checker deployment

Exposes potential image upgrades via prometheus metrics.

manifests/kube-system/kustomization.yaml

@@ -5,6 +5,7 @@ namespace: kube-system
 resources:
   - system-upgrade-controller
   - traefik
+  - version-checker
 
 configMapGenerator:
   - name: traefik

manifests/kube-system/version-checker/clusterrole.yaml

@@ -0,0 +1,8 @@
+kind: ClusterRole
+apiVersion: rbac.authorization.k8s.io/v1
+metadata:
+  name: version-checker
+rules:
+  - apiGroups: [""]
+    resources: ["pods"]
+    verbs: ["get", "watch", "list"]

manifests/kube-system/version-checker/clusterrolebinding.yaml

@@ -0,0 +1,12 @@
+kind: ClusterRoleBinding
+apiVersion: rbac.authorization.k8s.io/v1
+metadata:
+  name: version-checker
+roleRef:
+  apiGroup: rbac.authorization.k8s.io
+  kind: ClusterRole
+  name: version-checker
+subjects:
+  - kind: ServiceAccount
+    name: version-checker
+    namespace: kube-system

manifests/kube-system/version-checker/deployment.yaml

@@ -0,0 +1,30 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  labels:
+    app: version-checker
+  name: version-checker
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: version-checker
+  template:
+    metadata:
+      labels:
+        app: version-checker
+      annotations:
+        prometheus.io/path: /metrics
+        prometheus.io/port: "8080"
+        prometheus.io/scrape: "true"
+    spec:
+      serviceAccountName: version-checker
+      containers:
+        - image: quay.io/jetstack/version-checker:v0.2.1
+          imagePullPolicy: Always
+          ports:
+            - containerPort: 8080
+          name: version-checker
+          command: ["version-checker"]
+          args:
+            - --test-all-containers

manifests/kube-system/version-checker/kustomization.yaml

@@ -0,0 +1,8 @@
+apiVersion: kustomize.config.k8s.io/v1beta1
+kind: Kustomization
+
+resources:
+- clusterrolebinding.yaml
+- clusterrole.yaml
+- deployment.yaml
+- serviceaccount.yaml

manifests/kube-system/version-checker/serviceaccount.yaml

@@ -0,0 +1,4 @@
+apiVersion: v1
+kind: ServiceAccount
+metadata:
+  name: version-checker