Add Lease implementation to leaderelection package

Kubernetes-commit: 410175851c092dae63f72f7d12abf19b1b74e200

tools/leaderelection/resourcelock/interface.go

@@ -21,6 +21,7 @@ import (
 
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime"
+	coordinationv1 "k8s.io/client-go/kubernetes/typed/coordination/v1"
 	corev1 "k8s.io/client-go/kubernetes/typed/core/v1"
 )
 
@@ -28,6 +29,7 @@ const (
 	LeaderElectionRecordAnnotationKey = "control-plane.alpha.kubernetes.io/leader"
 	EndpointsResourceLock             = "endpoints"
 	ConfigMapsResourceLock            = "configmaps"
+	LeasesResourceLock                = "leases"
 )
 
 // LeaderElectionRecord is the record that is stored in the leader election annotation.
@@ -89,7 +91,7 @@ type Interface interface {
 }
 
 // Manufacture will create a lock of a given type according to the input parameters
-func New(lockType string, ns string, name string, client corev1.CoreV1Interface, rlc ResourceLockConfig) (Interface, error) {
+func New(lockType string, ns string, name string, coreClient corev1.CoreV1Interface, coordinationClient coordinationv1.CoordinationV1Interface, rlc ResourceLockConfig) (Interface, error) {
 	switch lockType {
 	case EndpointsResourceLock:
 		return &EndpointsLock{
@@ -97,7 +99,7 @@ func New(lockType string, ns string, name string, client corev1.CoreV1Interface,
 				Namespace: ns,
 				Name:      name,
 			},
-			Client:     client,
+			Client:     coreClient,
 			LockConfig: rlc,
 		}, nil
 	case ConfigMapsResourceLock:
@@ -106,7 +108,16 @@ func New(lockType string, ns string, name string, client corev1.CoreV1Interface,
 				Namespace: ns,
 				Name:      name,
 			},
-			Client:     client,
+			Client:     coreClient,
+			LockConfig: rlc,
+		}, nil
+	case LeasesResourceLock:
+		return &LeaseLock{
+			LeaseMeta: metav1.ObjectMeta{
+				Namespace: ns,
+				Name:      name,
+			},
+			Client:     coordinationClient,
 			LockConfig: rlc,
 		}, nil
 	default:

tools/leaderelection/resourcelock/leaselock.go

@@ -0,0 +1,124 @@
+/*
+Copyright 2018 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package resourcelock
+
+import (
+	"errors"
+	"fmt"
+
+	coordinationv1 "k8s.io/api/coordination/v1"
+	corev1 "k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	coordinationv1client "k8s.io/client-go/kubernetes/typed/coordination/v1"
+)
+
+type LeaseLock struct {
+	// LeaseMeta should contain a Name and a Namespace of a
+	// LeaseMeta object that the LeaderElector will attempt to lead.
+	LeaseMeta  metav1.ObjectMeta
+	Client     coordinationv1client.LeasesGetter
+	LockConfig ResourceLockConfig
+	lease      *coordinationv1.Lease
+}
+
+// Get returns the election record from a Lease spec
+func (ll *LeaseLock) Get() (*LeaderElectionRecord, error) {
+	var err error
+	ll.lease, err = ll.Client.Leases(ll.LeaseMeta.Namespace).Get(ll.LeaseMeta.Name, metav1.GetOptions{})
+	if err != nil {
+		return nil, err
+	}
+	return LeaseSpecToLeaderElectionRecord(&ll.lease.Spec), nil
+}
+
+// Create attempts to create a Lease
+func (ll *LeaseLock) Create(ler LeaderElectionRecord) error {
+	var err error
+	ll.lease, err = ll.Client.Leases(ll.LeaseMeta.Namespace).Create(&coordinationv1.Lease{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      ll.LeaseMeta.Name,
+			Namespace: ll.LeaseMeta.Namespace,
+		},
+		Spec: LeaderElectionRecordToLeaseSpec(&ler),
+	})
+	return err
+}
+
+// Update will update an existing Lease spec.
+func (ll *LeaseLock) Update(ler LeaderElectionRecord) error {
+	if ll.lease == nil {
+		return errors.New("lease not initialized, call get or create first")
+	}
+	ll.lease.Spec = LeaderElectionRecordToLeaseSpec(&ler)
+	var err error
+	ll.lease, err = ll.Client.Leases(ll.LeaseMeta.Namespace).Update(ll.lease)
+	return err
+}
+
+// RecordEvent in leader election while adding meta-data
+func (ll *LeaseLock) RecordEvent(s string) {
+	if ll.LockConfig.EventRecorder == nil {
+		return
+	}
+	events := fmt.Sprintf("%v %v", ll.LockConfig.Identity, s)
+	ll.LockConfig.EventRecorder.Eventf(&coordinationv1.Lease{ObjectMeta: ll.lease.ObjectMeta}, corev1.EventTypeNormal, "LeaderElection", events)
+}
+
+// Describe is used to convert details on current resource lock
+// into a string
+func (ll *LeaseLock) Describe() string {
+	return fmt.Sprintf("%v/%v", ll.LeaseMeta.Namespace, ll.LeaseMeta.Name)
+}
+
+// returns the Identity of the lock
+func (ll *LeaseLock) Identity() string {
+	return ll.LockConfig.Identity
+}
+
+func LeaseSpecToLeaderElectionRecord(spec *coordinationv1.LeaseSpec) *LeaderElectionRecord {
+	holderIdentity := ""
+	if spec.HolderIdentity != nil {
+		holderIdentity = *spec.HolderIdentity
+	}
+	leaseDurationSeconds := 0
+	if spec.LeaseDurationSeconds != nil {
+		leaseDurationSeconds = int(*spec.LeaseDurationSeconds)
+	}
+	leaseTransitions := 0
+	if spec.LeaseTransitions != nil {
+		leaseTransitions = int(*spec.LeaseTransitions)
+	}
+	return &LeaderElectionRecord{
+		HolderIdentity:       holderIdentity,
+		LeaseDurationSeconds: leaseDurationSeconds,
+		AcquireTime:          metav1.Time{spec.AcquireTime.Time},
+		RenewTime:            metav1.Time{spec.RenewTime.Time},
+		LeaderTransitions:    leaseTransitions,
+	}
+}
+
+func LeaderElectionRecordToLeaseSpec(ler *LeaderElectionRecord) coordinationv1.LeaseSpec {
+	leaseDurationSeconds := int32(ler.LeaseDurationSeconds)
+	leaseTransitions := int32(ler.LeaderTransitions)
+	return coordinationv1.LeaseSpec{
+		HolderIdentity:       &ler.HolderIdentity,
+		LeaseDurationSeconds: &leaseDurationSeconds,
+		AcquireTime:          &metav1.MicroTime{ler.AcquireTime.Time},
+		RenewTime:            &metav1.MicroTime{ler.RenewTime.Time},
+		LeaseTransitions:     &leaseTransitions,
+	}
+}