Fix leader-election RBAC, Go version drift, PVC churn, cron names, apply order

Addresses PR review + acceptance findings:

- Add leader-election RBAC: namespaced Role (coordination leases +
  events) and RoleBinding to the operator ServiceAccount, so controllers
  actually start under --leader-elect instead of looping on "leases
  forbidden". Verified in a kind cluster: lease acquired, both
  controllers start workers.
- Align Go versions: bump Dockerfile.operator to golang:1.26-alpine and
  CI images to golang:1.26 to match go.mod (go 1.26.5); set
  GOTOOLCHAIN=local so the image build stays hermetic (no toolchain
  download).
- PVC controller: add an annotation predicate so only PVCs carrying (or
  transitioning off of) backups.unkin.net/schedule enqueue, eliminating
  reconcile churn from unannotated PVCs while keeping the teardown path.
- Cron validator: accept alphabetic month/day-of-week names (MON, JAN,
  MON-FRI) that k8up and CNPG's robfig/cron accept, still rejecting
  unknown names; add unit tests for both mapping paths.
- Deploy ordering: extract the Namespace into its own manifest and add a
  config/kustomization.yaml so `kubectl apply -k config` creates the
  namespace first; document it in the README.
- Note the credential-less push precedent (jellyfin-ha) in docker.yaml.

.woodpecker/docker.yaml

@@ -3,6 +3,8 @@ when:
     ref: refs/tags/v*
 
 steps:
+  # No push credentials: the in-cluster runner has push access to the artifactapi
+  # docker-internal registry (same credential-less pattern as jellyfin-ha).
   - name: docker
     image: woodpeckerci/plugin-docker-buildx
     settings:

.woodpecker/pre-commit.yaml

@@ -3,7 +3,7 @@ when:
 
 steps:
   - name: pre-commit
-    image: golang:1.25
+    image: golang:1.26
     commands:
       - test -z "$(gofmt -l cmd/ internal/)"
       - go vet -mod=vendor ./...

.woodpecker/test.yaml

@@ -3,7 +3,7 @@ when:
 
 steps:
   - name: test
-    image: golang:1.25
+    image: golang:1.26
     commands:
       # Fetch the envtest control-plane binaries; the controller tests skip
       # gracefully if this cannot be downloaded.

Dockerfile.operator

@@ -1,4 +1,8 @@
-FROM golang:1.25-alpine AS builder
+FROM golang:1.26-alpine AS builder
+
+# Fail rather than download a toolchain: the base image must already satisfy the
+# go directive in go.mod so the build stays hermetic (no network at build time).
+ENV GOTOOLCHAIN=local
 
 WORKDIR /build
 

README.md

@@ -38,6 +38,19 @@ The operator resolves `destination` names against a ConfigMap in its own
 namespace (`autobackup-operator/autobackup-destinations` by default). See
 `config/samples/destinations.yaml`.
 
+## Deploy
+
+```sh
+kubectl apply -k config
+```
+
+The `config/kustomization.yaml` orders the `Namespace` first so the
+ServiceAccount, RBAC and Deployment land in an existing namespace. RBAC covers
+both the controllers' resources (`config/rbac/role.yaml`) and the leader-election
+lease/events the manager needs when run with `--leader-elect`
+(`config/rbac/leader_election_role.yaml`). Then create the destinations
+ConfigMap (see `config/samples/destinations.yaml`).
+
 ## Schedule mapping
 
 - **k8up** accepts cron nicknames natively and 5-field cron expressions; the

config/kustomization.yaml

@@ -0,0 +1,13 @@
+apiVersion: kustomize.config.k8s.io/v1beta1
+kind: Kustomization
+
+# Namespace is listed first and kustomize's kind ordering applies it ahead of the
+# ServiceAccount/RoleBinding/Deployment, so `kubectl apply -k config` succeeds on
+# a clean cluster without a separate namespace-creation step.
+resources:
+  - namespace.yaml
+  - rbac/service_account.yaml
+  - rbac/role.yaml
+  - rbac/leader_election_role.yaml
+  - rbac/leader_election_role_binding.yaml
+  - manager/manager.yaml

config/manager/manager.yaml

@@ -1,8 +1,3 @@
-apiVersion: v1
-kind: Namespace
-metadata:
-  name: autobackup-operator
----
 apiVersion: apps/v1
 kind: Deployment
 metadata:

config/namespace.yaml

@@ -0,0 +1,4 @@
+apiVersion: v1
+kind: Namespace
+metadata:
+  name: autobackup-operator

config/rbac/leader_election_role.yaml

@@ -0,0 +1,40 @@
+---
+# Namespaced permissions the controller-manager needs for leader election
+# (--leader-elect). The lease lock is created in the operator's own namespace.
+apiVersion: rbac.authorization.k8s.io/v1
+kind: Role
+metadata:
+  name: autobackup-operator-leader-election
+  namespace: autobackup-operator
+rules:
+- apiGroups:
+  - ""
+  resources:
+  - configmaps
+  verbs:
+  - get
+  - list
+  - watch
+  - create
+  - update
+  - patch
+  - delete
+- apiGroups:
+  - coordination.k8s.io
+  resources:
+  - leases
+  verbs:
+  - get
+  - list
+  - watch
+  - create
+  - update
+  - patch
+  - delete
+- apiGroups:
+  - ""
+  resources:
+  - events
+  verbs:
+  - create
+  - patch

config/rbac/leader_election_role_binding.yaml

@@ -0,0 +1,14 @@
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: RoleBinding
+metadata:
+  name: autobackup-operator-leader-election
+  namespace: autobackup-operator
+roleRef:
+  apiGroup: rbac.authorization.k8s.io
+  kind: Role
+  name: autobackup-operator-leader-election
+subjects:
+  - kind: ServiceAccount
+    name: autobackup-operator
+    namespace: autobackup-operator

internal/controller/pvc_controller.go

@@ -9,9 +9,12 @@ import (
 	corev1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	ctrl "sigs.k8s.io/controller-runtime"
+	"sigs.k8s.io/controller-runtime/pkg/builder"
 	"sigs.k8s.io/controller-runtime/pkg/client"
 	"sigs.k8s.io/controller-runtime/pkg/controller/controllerutil"
+	"sigs.k8s.io/controller-runtime/pkg/event"
 	"sigs.k8s.io/controller-runtime/pkg/log"
+	"sigs.k8s.io/controller-runtime/pkg/predicate"
 )
 
 // PVCReconciler backs up annotated PersistentVolumeClaims by provisioning an S3
@@ -140,9 +143,28 @@ func secretKeyRef(name, key string) *corev1.SecretKeySelector {
 	}
 }
 
+// hasScheduleAnnotation reports whether an object carries the schedule
+// annotation that marks it for management.
+func hasScheduleAnnotation(o client.Object) bool {
+	_, ok := o.GetAnnotations()[annSchedule]
+	return ok
+}
+
+// schedulePredicate limits reconciles to PVCs that carry (or, on update, used to
+// carry) the schedule annotation, so unannotated PVCs no longer churn the queue
+// on every resync while the annotation-removed teardown path still fires.
+var schedulePredicate = predicate.Funcs{
+	CreateFunc:  func(e event.CreateEvent) bool { return hasScheduleAnnotation(e.Object) },
+	DeleteFunc:  func(e event.DeleteEvent) bool { return hasScheduleAnnotation(e.Object) },
+	GenericFunc: func(e event.GenericEvent) bool { return hasScheduleAnnotation(e.Object) },
+	UpdateFunc: func(e event.UpdateEvent) bool {
+		return hasScheduleAnnotation(e.ObjectOld) || hasScheduleAnnotation(e.ObjectNew)
+	},
+}
+
 func (r *PVCReconciler) SetupWithManager(mgr ctrl.Manager) error {
 	return ctrl.NewControllerManagedBy(mgr).
-		For(&corev1.PersistentVolumeClaim{}).
+		For(&corev1.PersistentVolumeClaim{}, builder.WithPredicates(schedulePredicate)).
 		Owns(&k8upv1.Schedule{}).
 		Named("pvc-autobackup").
 		Complete(r)

internal/controller/pvc_controller_test.go

@@ -13,9 +13,42 @@ import (
 	"k8s.io/apimachinery/pkg/types"
 	clientgoscheme "k8s.io/client-go/kubernetes/scheme"
 	"k8s.io/client-go/tools/record"
+	"sigs.k8s.io/controller-runtime/pkg/event"
 	"sigs.k8s.io/controller-runtime/pkg/reconcile"
 )
 
+func pvcWith(ann map[string]string) *corev1.PersistentVolumeClaim {
+	return &corev1.PersistentVolumeClaim{ObjectMeta: metav1.ObjectMeta{Name: "data", Namespace: "ns", Annotations: ann}}
+}
+
+func TestSchedulePredicate(t *testing.T) {
+	annotated := pvcWith(map[string]string{annSchedule: "@daily"})
+	plain := pvcWith(nil)
+
+	if schedulePredicate.Create(event.CreateEvent{Object: plain}) {
+		t.Error("create of unannotated PVC should be filtered out")
+	}
+	if !schedulePredicate.Create(event.CreateEvent{Object: annotated}) {
+		t.Error("create of annotated PVC should enqueue")
+	}
+	if schedulePredicate.Generic(event.GenericEvent{Object: plain}) {
+		t.Error("generic event for unannotated PVC should be filtered out")
+	}
+	// Annotation removed: old had it, new does not -> must still enqueue so
+	// teardown runs.
+	if !schedulePredicate.Update(event.UpdateEvent{ObjectOld: annotated, ObjectNew: plain}) {
+		t.Error("annotation removal should enqueue for teardown")
+	}
+	// Annotation added.
+	if !schedulePredicate.Update(event.UpdateEvent{ObjectOld: plain, ObjectNew: annotated}) {
+		t.Error("annotation addition should enqueue")
+	}
+	// Neither old nor new annotated -> no enqueue.
+	if schedulePredicate.Update(event.UpdateEvent{ObjectOld: plain, ObjectNew: plain}) {
+		t.Error("update of unannotated PVC should be filtered out")
+	}
+}
+
 func TestPVCReconcile(t *testing.T) {
 	requireEnvtest(t)
 	ctx := context.Background()

internal/controller/schedule.go

@@ -76,6 +76,14 @@ func ScheduleForCNPG(in string) (string, error) {
 	}
 }
 
+// cronNames are the alphabetic month and day-of-week names robfig/cron (used by
+// k8up and CloudNativePG) accepts, case-insensitively, e.g. "MON" or "JAN".
+var cronNames = map[string]bool{
+	"JAN": true, "FEB": true, "MAR": true, "APR": true, "MAY": true, "JUN": true,
+	"JUL": true, "AUG": true, "SEP": true, "OCT": true, "NOV": true, "DEC": true,
+	"SUN": true, "MON": true, "TUE": true, "WED": true, "THU": true, "FRI": true, "SAT": true,
+}
+
 func validateCronFields(s string, want int) error {
 	fields := strings.Fields(s)
 	if len(fields) != want {
@@ -85,11 +93,34 @@ func validateCronFields(s string, want int) error {
 		if f == "" {
 			return fmt.Errorf("cron %q has an empty field", s)
 		}
-		for _, r := range f {
-			if !isCronRune(r) {
-				return fmt.Errorf("cron field %q contains invalid character %q", f, string(r))
+		if err := validateCronField(f); err != nil {
+			return err
 		}
 	}
+	return nil
+}
+
+// validateCronField accepts cron symbols plus known alphabetic month/day names
+// (e.g. MON-FRI, JAN); an unknown alphabetic run like "foo" is rejected.
+func validateCronField(f string) error {
+	runes := []rune(f)
+	for i := 0; i < len(runes); {
+		if isLetter(runes[i]) {
+			j := i
+			for j < len(runes) && isLetter(runes[j]) {
+				j++
+			}
+			name := strings.ToUpper(string(runes[i:j]))
+			if !cronNames[name] {
+				return fmt.Errorf("cron field %q contains unknown name %q", f, string(runes[i:j]))
+			}
+			i = j
+			continue
+		}
+		if !isCronRune(runes[i]) {
+			return fmt.Errorf("cron field %q contains invalid character %q", f, string(runes[i]))
+		}
+		i++
 	}
 	return nil
 }
@@ -97,3 +128,7 @@ func validateCronFields(s string, want int) error {
 func isCronRune(r rune) bool {
 	return (r >= '0' && r <= '9') || r == '*' || r == '/' || r == ',' || r == '-' || r == '?'
 }
+
+func isLetter(r rune) bool {
+	return (r >= 'a' && r <= 'z') || (r >= 'A' && r <= 'Z')
+}

internal/controller/schedule_test.go

@@ -16,10 +16,13 @@ func TestScheduleForK8up(t *testing.T) {
 		{"0 2 * * *", "0 2 * * *", false},
 		{"*/15 * * * *", "*/15 * * * *", false},
 		{"0 0 * * 1-5", "0 0 * * 1-5", false},
+		{"0 0 1 * MON", "0 0 1 * MON", false},         // alphabetic day-of-week
+		{"0 0 1 JAN *", "0 0 1 JAN *", false},         // alphabetic month
+		{"0 0 * * mon-fri", "0 0 * * mon-fri", false}, // lowercase range of names
 		{"@bogus", "", true},
 		{"0 2 * *", "", true},     // 4 fields
 		{"0 0 0 * * *", "", true}, // 6 fields not valid for k8up
-		{"0 2 * * foo", "", true}, // invalid chars
+		{"0 2 * * foo", "", true}, // unknown alphabetic name
 		{"", "", true},
 	}
 	for _, c := range cases {
@@ -57,10 +60,12 @@ func TestScheduleForCNPG(t *testing.T) {
 		{"*/15 * * * *", "0 */15 * * * *", false},
 		{"30 0 3 * * *", "30 0 3 * * *", false}, // already 6-field
 		{"  @daily ", "0 0 0 * * *", false},
+		{"0 0 1 * MON", "0 0 0 1 * MON", false},   // 5-field w/ alphabetic dow gains seconds
+		{"0 0 0 1 JAN *", "0 0 0 1 JAN *", false}, // 6-field w/ alphabetic month
 		{"@bogus", "", true},
 		{"0 2 * *", "", true},       // 4 fields
 		{"1 2 3 4 5 6 7", "", true}, // 7 fields
-		{"0 2 * * bad", "", true},   // invalid chars
+		{"0 2 * * bad", "", true},   // unknown alphabetic name
 		{"", "", true},
 	}
 	for _, c := range cases {