Merge pull request #70778 from wongma7/lease

Add Lease implementation to leaderelection package

Kubernetes-commit: d027ecfa97444a419f42744e6a3faeaed52aed8e

tools/leaderelection/leaderelection_test.go

@@ -17,28 +17,47 @@ limitations under the License.
 package leaderelection
 
 import (
+	"encoding/json"
 	"fmt"
 	"sync"
 	"testing"
 	"time"
 
-	"k8s.io/api/core/v1"
+	coordinationv1 "k8s.io/api/coordination/v1"
+	corev1 "k8s.io/api/core/v1"
+	"k8s.io/apimachinery/pkg/api/equality"
 	"k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/util/clock"
-	fakecorev1 "k8s.io/client-go/kubernetes/typed/core/v1/fake"
+	"k8s.io/apimachinery/pkg/util/diff"
-	core "k8s.io/client-go/testing"
+	"k8s.io/client-go/kubernetes/fake"
+	fakeclient "k8s.io/client-go/testing"
 	rl "k8s.io/client-go/tools/leaderelection/resourcelock"
 	"k8s.io/client-go/tools/record"
 )
 
-func createLockObject(objectType string, objectMeta metav1.ObjectMeta) (obj runtime.Object) {
+func createLockObject(objectType, namespace, name string, record rl.LeaderElectionRecord) (obj runtime.Object) {
+	objectMeta := metav1.ObjectMeta{
+		Namespace: namespace,
+		Name:      name,
+	}
 	switch objectType {
 	case "endpoints":
-		obj = &v1.Endpoints{ObjectMeta: objectMeta}
+		recordBytes, _ := json.Marshal(record)
+		objectMeta.Annotations = map[string]string{
+			rl.LeaderElectionRecordAnnotationKey: string(recordBytes),
+		}
+		obj = &corev1.Endpoints{ObjectMeta: objectMeta}
 	case "configmaps":
-		obj = &v1.ConfigMap{ObjectMeta: objectMeta}
+		recordBytes, _ := json.Marshal(record)
+		objectMeta.Annotations = map[string]string{
+			rl.LeaderElectionRecordAnnotationKey: string(recordBytes),
+		}
+		obj = &corev1.ConfigMap{ObjectMeta: objectMeta}
+	case "leases":
+		spec := rl.LeaderElectionRecordToLeaseSpec(&record)
+		obj = &coordinationv1.Lease{ObjectMeta: objectMeta, Spec: spec}
 	default:
 		panic("unexpected objType:" + objectType)
 	}
@@ -60,7 +79,7 @@ func testTryAcquireOrRenew(t *testing.T, objectType string) {
 		observedTime   time.Time
 		reactors       []struct {
 			verb     string
-			reaction core.ReactionFunc
+			reaction fakeclient.ReactionFunc
 		}
 
 		expectSuccess    bool
@@ -71,18 +90,18 @@ func testTryAcquireOrRenew(t *testing.T, objectType string) {
 			name: "acquire from no object",
 			reactors: []struct {
 				verb     string
-				reaction core.ReactionFunc
+				reaction fakeclient.ReactionFunc
 			}{
 				{
 					verb: "get",
-					reaction: func(action core.Action) (handled bool, ret runtime.Object, err error) {
+					reaction: func(action fakeclient.Action) (handled bool, ret runtime.Object, err error) {
-						return true, nil, errors.NewNotFound(action.(core.GetAction).GetResource().GroupResource(), action.(core.GetAction).GetName())
+						return true, nil, errors.NewNotFound(action.(fakeclient.GetAction).GetResource().GroupResource(), action.(fakeclient.GetAction).GetName())
 					},
 				},
 				{
 					verb: "create",
-					reaction: func(action core.Action) (handled bool, ret runtime.Object, err error) {
+					reaction: func(action fakeclient.Action) (handled bool, ret runtime.Object, err error) {
-						return true, action.(core.CreateAction).GetObject(), nil
+						return true, action.(fakeclient.CreateAction).GetObject(), nil
 					},
 				},
 			},
@@ -93,22 +112,18 @@ func testTryAcquireOrRenew(t *testing.T, objectType string) {
 			name: "acquire from unled object",
 			reactors: []struct {
 				verb     string
-				reaction core.ReactionFunc
+				reaction fakeclient.ReactionFunc
 			}{
 				{
 					verb: "get",
-					reaction: func(action core.Action) (handled bool, ret runtime.Object, err error) {
+					reaction: func(action fakeclient.Action) (handled bool, ret runtime.Object, err error) {
-						objectMeta := metav1.ObjectMeta{
+						return true, createLockObject(objectType, action.GetNamespace(), action.(fakeclient.GetAction).GetName(), rl.LeaderElectionRecord{}), nil
-							Namespace: action.GetNamespace(),
-							Name:      action.(core.GetAction).GetName(),
-						}
-						return true, createLockObject(objectType, objectMeta), nil
 					},
 				},
 				{
 					verb: "update",
-					reaction: func(action core.Action) (handled bool, ret runtime.Object, err error) {
+					reaction: func(action fakeclient.Action) (handled bool, ret runtime.Object, err error) {
-						return true, action.(core.CreateAction).GetObject(), nil
+						return true, action.(fakeclient.CreateAction).GetObject(), nil
 					},
 				},
 			},
@@ -121,25 +136,18 @@ func testTryAcquireOrRenew(t *testing.T, objectType string) {
 			name: "acquire from led, unacked object",
 			reactors: []struct {
 				verb     string
-				reaction core.ReactionFunc
+				reaction fakeclient.ReactionFunc
 			}{
 				{
 					verb: "get",
-					reaction: func(action core.Action) (handled bool, ret runtime.Object, err error) {
+					reaction: func(action fakeclient.Action) (handled bool, ret runtime.Object, err error) {
-						objectMeta := metav1.ObjectMeta{
+						return true, createLockObject(objectType, action.GetNamespace(), action.(fakeclient.GetAction).GetName(), rl.LeaderElectionRecord{HolderIdentity: "bing"}), nil
-							Namespace: action.GetNamespace(),
-							Name:      action.(core.GetAction).GetName(),
-							Annotations: map[string]string{
-								rl.LeaderElectionRecordAnnotationKey: `{"holderIdentity":"bing"}`,
-							},
-						}
-						return true, createLockObject(objectType, objectMeta), nil
 					},
 				},
 				{
 					verb: "update",
-					reaction: func(action core.Action) (handled bool, ret runtime.Object, err error) {
+					reaction: func(action fakeclient.Action) (handled bool, ret runtime.Object, err error) {
-						return true, action.(core.CreateAction).GetObject(), nil
+						return true, action.(fakeclient.CreateAction).GetObject(), nil
 					},
 				},
 			},
@@ -154,25 +162,18 @@ func testTryAcquireOrRenew(t *testing.T, objectType string) {
 			name: "acquire from empty led, acked object",
 			reactors: []struct {
 				verb     string
-				reaction core.ReactionFunc
+				reaction fakeclient.ReactionFunc
 			}{
 				{
 					verb: "get",
-					reaction: func(action core.Action) (handled bool, ret runtime.Object, err error) {
+					reaction: func(action fakeclient.Action) (handled bool, ret runtime.Object, err error) {
-						objectMeta := metav1.ObjectMeta{
+						return true, createLockObject(objectType, action.GetNamespace(), action.(fakeclient.GetAction).GetName(), rl.LeaderElectionRecord{HolderIdentity: ""}), nil
-							Namespace: action.GetNamespace(),
-							Name:      action.(core.GetAction).GetName(),
-							Annotations: map[string]string{
-								rl.LeaderElectionRecordAnnotationKey: `{"holderIdentity":""}`,
-							},
-						}
-						return true, createLockObject(objectType, objectMeta), nil
 					},
 				},
 				{
 					verb: "update",
-					reaction: func(action core.Action) (handled bool, ret runtime.Object, err error) {
+					reaction: func(action fakeclient.Action) (handled bool, ret runtime.Object, err error) {
-						return true, action.(core.CreateAction).GetObject(), nil
+						return true, action.(fakeclient.CreateAction).GetObject(), nil
 					},
 				},
 			},
@@ -186,19 +187,12 @@ func testTryAcquireOrRenew(t *testing.T, objectType string) {
 			name: "don't acquire from led, acked object",
 			reactors: []struct {
 				verb     string
-				reaction core.ReactionFunc
+				reaction fakeclient.ReactionFunc
 			}{
 				{
 					verb: "get",
-					reaction: func(action core.Action) (handled bool, ret runtime.Object, err error) {
+					reaction: func(action fakeclient.Action) (handled bool, ret runtime.Object, err error) {
-						objectMeta := metav1.ObjectMeta{
+						return true, createLockObject(objectType, action.GetNamespace(), action.(fakeclient.GetAction).GetName(), rl.LeaderElectionRecord{HolderIdentity: "bing"}), nil
-							Namespace: action.GetNamespace(),
-							Name:      action.(core.GetAction).GetName(),
-							Annotations: map[string]string{
-								rl.LeaderElectionRecordAnnotationKey: `{"holderIdentity":"bing"}`,
-							},
-						}
-						return true, createLockObject(objectType, objectMeta), nil
 					},
 				},
 			},
@@ -211,25 +205,18 @@ func testTryAcquireOrRenew(t *testing.T, objectType string) {
 			name: "renew already acquired object",
 			reactors: []struct {
 				verb     string
-				reaction core.ReactionFunc
+				reaction fakeclient.ReactionFunc
 			}{
 				{
 					verb: "get",
-					reaction: func(action core.Action) (handled bool, ret runtime.Object, err error) {
+					reaction: func(action fakeclient.Action) (handled bool, ret runtime.Object, err error) {
-						objectMeta := metav1.ObjectMeta{
+						return true, createLockObject(objectType, action.GetNamespace(), action.(fakeclient.GetAction).GetName(), rl.LeaderElectionRecord{HolderIdentity: "baz"}), nil
-							Namespace: action.GetNamespace(),
-							Name:      action.(core.GetAction).GetName(),
-							Annotations: map[string]string{
-								rl.LeaderElectionRecordAnnotationKey: `{"holderIdentity":"baz"}`,
-							},
-						}
-						return true, createLockObject(objectType, objectMeta), nil
 					},
 				},
 				{
 					verb: "update",
-					reaction: func(action core.Action) (handled bool, ret runtime.Object, err error) {
+					reaction: func(action fakeclient.Action) (handled bool, ret runtime.Object, err error) {
-						return true, action.(core.CreateAction).GetObject(), nil
+						return true, action.(fakeclient.CreateAction).GetObject(), nil
 					},
 				},
 			},
@@ -255,11 +242,11 @@ func testTryAcquireOrRenew(t *testing.T, objectType string) {
 				Identity:      "baz",
 				EventRecorder: &record.FakeRecorder{},
 			}
-			c := &fakecorev1.FakeCoreV1{Fake: &core.Fake{}}
+			c := &fake.Clientset{}
 			for _, reactor := range test.reactors {
 				c.AddReactor(reactor.verb, objectType, reactor.reaction)
 			}
-			c.AddReactor("*", "*", func(action core.Action) (bool, runtime.Object, error) {
+			c.AddReactor("*", "*", func(action fakeclient.Action) (bool, runtime.Object, error) {
 				t.Errorf("unreachable action. testclient called too many times: %+v", action)
 				return true, nil, fmt.Errorf("unreachable action")
 			})
@@ -269,13 +256,19 @@ func testTryAcquireOrRenew(t *testing.T, objectType string) {
 				lock = &rl.EndpointsLock{
 					EndpointsMeta: objectMeta,
 					LockConfig:    resourceLockConfig,
-					Client:        c,
+					Client:        c.CoreV1(),
 				}
 			case "configmaps":
 				lock = &rl.ConfigMapLock{
 					ConfigMapMeta: objectMeta,
 					LockConfig:    resourceLockConfig,
-					Client:        c,
+					Client:        c.CoreV1(),
+				}
+			case "leases":
+				lock = &rl.LeaseLock{
+					LeaseMeta:  objectMeta,
+					LockConfig: resourceLockConfig,
+					Client:     c.CoordinationV1(),
 				}
 			}
 
@@ -328,3 +321,34 @@ func testTryAcquireOrRenew(t *testing.T, objectType string) {
 func TestTryAcquireOrRenewConfigMaps(t *testing.T) {
 	testTryAcquireOrRenew(t, "configmaps")
 }
+
+// Will test leader election using lease as the resource
+func TestTryAcquireOrRenewLeases(t *testing.T) {
+	testTryAcquireOrRenew(t, "leases")
+}
+
+func TestLeaseSpecToLeaderElectionRecordRoundTrip(t *testing.T) {
+	holderIdentity := "foo"
+	leaseDurationSeconds := int32(10)
+	leaseTransitions := int32(1)
+	oldSpec := coordinationv1.LeaseSpec{
+		HolderIdentity:       &holderIdentity,
+		LeaseDurationSeconds: &leaseDurationSeconds,
+		AcquireTime:          &metav1.MicroTime{time.Now()},
+		RenewTime:            &metav1.MicroTime{time.Now()},
+		LeaseTransitions:     &leaseTransitions,
+	}
+
+	oldRecord := rl.LeaseSpecToLeaderElectionRecord(&oldSpec)
+	newSpec := rl.LeaderElectionRecordToLeaseSpec(oldRecord)
+
+	if !equality.Semantic.DeepEqual(oldSpec, newSpec) {
+		t.Errorf("diff: %v", diff.ObjectReflectDiff(oldSpec, newSpec))
+	}
+
+	newRecord := rl.LeaseSpecToLeaderElectionRecord(&newSpec)
+
+	if !equality.Semantic.DeepEqual(oldRecord, newRecord) {
+		t.Errorf("diff: %v", diff.ObjectReflectDiff(oldRecord, newRecord))
+	}
+}

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,
+	}
+}