Merge pull request #16830 from mikedanese/leader-election

pkg/client/leaderelection/leaderelection_test.go

+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+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 leaderelection implements leader election of a set of endpoints.
+// It uses an annotation in the endpoints object to store the record of the
+// election state.
+
+package leaderelection
+
+import (
+	"fmt"
+	"testing"
+	"time"
+
+	"k8s.io/kubernetes/pkg/api"
+	"k8s.io/kubernetes/pkg/api/errors"
+	"k8s.io/kubernetes/pkg/api/unversioned"
+	"k8s.io/kubernetes/pkg/client/record"
+	"k8s.io/kubernetes/pkg/client/unversioned/testclient"
+	"k8s.io/kubernetes/pkg/runtime"
+)
+
+func TestTryAcquireOrRenew(t *testing.T) {
+	future := time.Now().Add(1000 * time.Hour)
+
+	tests := []struct {
+		observedRecord LeaderElectionRecord
+		observedTime   time.Time
+		reactors       []struct {
+			verb     string
+			reaction testclient.ReactionFunc
+		}
+
+		expectSuccess bool
+		outHolder     string
+	}{
+		// acquire from no endpoints
+		{
+			reactors: []struct {
+				verb     string
+				reaction testclient.ReactionFunc
+			}{
+				{
+					verb: "get",
+					reaction: func(action testclient.Action) (handled bool, ret runtime.Object, err error) {
+						return true, nil, errors.NewNotFound(action.GetVerb(), action.(testclient.GetAction).GetName())
+					},
+				},
+				{
+					verb: "create",
+					reaction: func(action testclient.Action) (handled bool, ret runtime.Object, err error) {
+						return true, action.(testclient.CreateAction).GetObject().(*api.Endpoints), nil
+					},
+				},
+			},
+			expectSuccess: true,
+			outHolder:     "baz",
+		},
+		// acquire from unled endpoints
+		{
+			reactors: []struct {
+				verb     string
+				reaction testclient.ReactionFunc
+			}{
+				{
+					verb: "get",
+					reaction: func(action testclient.Action) (handled bool, ret runtime.Object, err error) {
+						return true, &api.Endpoints{
+							ObjectMeta: api.ObjectMeta{
+								Namespace: action.GetNamespace(),
+								Name:      action.(testclient.GetAction).GetName(),
+							},
+						}, nil
+					},
+				},
+				{
+					verb: "update",
+					reaction: func(action testclient.Action) (handled bool, ret runtime.Object, err error) {
+						return true, action.(testclient.CreateAction).GetObject().(*api.Endpoints), nil
+					},
+				},
+			},
+			expectSuccess: true,
+			outHolder:     "baz",
+		},
+		// acquire from led, unacked endpoints
+		{
+			reactors: []struct {
+				verb     string
+				reaction testclient.ReactionFunc
+			}{
+				{
+					verb: "get",
+					reaction: func(action testclient.Action) (handled bool, ret runtime.Object, err error) {
+						return true, &api.Endpoints{
+							ObjectMeta: api.ObjectMeta{
+								Namespace: action.GetNamespace(),
+								Name:      action.(testclient.GetAction).GetName(),
+							},
+						}, nil
+					},
+				},
+				{
+					verb: "update",
+					reaction: func(action testclient.Action) (handled bool, ret runtime.Object, err error) {
+						return true, action.(testclient.CreateAction).GetObject().(*api.Endpoints), nil
+					},
+				},
+			},
+			expectSuccess: true,
+			outHolder:     "baz",
+		},
+		// don't acquire from led, acked endpoints
+		{
+			reactors: []struct {
+				verb     string
+				reaction testclient.ReactionFunc
+			}{
+				{
+					verb: "get",
+					reaction: func(action testclient.Action) (handled bool, ret runtime.Object, err error) {
+						return true, &api.Endpoints{
+							ObjectMeta: api.ObjectMeta{
+								Namespace: action.GetNamespace(),
+								Name:      action.(testclient.GetAction).GetName(),
+								Annotations: map[string]string{
+									LeaderElectionRecordAnnotationKey: `{"holderIdentity":"bing"}`,
+								},
+							},
+						}, nil
+					},
+				},
+			},
+			observedTime: future,
+
+			expectSuccess: false,
+			outHolder:     "bing",
+		},
+		// renew already acquired endpoints
+		{
+			reactors: []struct {
+				verb     string
+				reaction testclient.ReactionFunc
+			}{
+				{
+					verb: "get",
+					reaction: func(action testclient.Action) (handled bool, ret runtime.Object, err error) {
+						return true, &api.Endpoints{
+							ObjectMeta: api.ObjectMeta{
+								Namespace: action.GetNamespace(),
+								Name:      action.(testclient.GetAction).GetName(),
+								Annotations: map[string]string{
+									LeaderElectionRecordAnnotationKey: `{"holderIdentity":"baz"}`,
+								},
+							},
+						}, nil
+					},
+				},
+				{
+					verb: "update",
+					reaction: func(action testclient.Action) (handled bool, ret runtime.Object, err error) {
+						return true, action.(testclient.CreateAction).GetObject().(*api.Endpoints), nil
+					},
+				},
+			},
+			observedTime:   future,
+			observedRecord: LeaderElectionRecord{HolderIdentity: "baz"},
+
+			expectSuccess: true,
+			outHolder:     "baz",
+		},
+	}
+
+	lec := LeaderElectionConfig{
+		EndpointsMeta: api.ObjectMeta{Namespace: "foo", Name: "bar"},
+		Identity:      "baz",
+		EventRecorder: &record.FakeRecorder{},
+		LeaseDuration: 10 * time.Second,
+	}
+
+	for i, test := range tests {
+		c := &testclient.Fake{}
+		for _, reactor := range test.reactors {
+			c.AddReactor(reactor.verb, "endpoints", reactor.reaction)
+		}
+		c.AddReactor("*", "*", func(action testclient.Action) (bool, runtime.Object, error) {
+			t.Errorf("[%v] unreachable action. testclient called too many times: %+v", i, action)
+			return true, nil, fmt.Errorf("uncreachable action")
+		})
+
+		le := &LeaderElector{
+			config:         lec,
+			observedRecord: test.observedRecord,
+			observedTime:   test.observedTime,
+		}
+		le.config.Client = c
+
+		if test.expectSuccess != le.tryAcquireOrRenew() {
+			t.Errorf("[%v]unexpected result of tryAcquireOrRenew: [succeded=%v]", i, !test.expectSuccess)
+		}
+
+		le.observedRecord.AcquireTime = unversioned.Time{}
+		le.observedRecord.RenewTime = unversioned.Time{}
+		if le.observedRecord.HolderIdentity != test.outHolder {
+			t.Errorf("[%v]expected holder:\n\t%+v\ngot:\n\t%+v", i, test.outHolder, le.observedRecord.HolderIdentity)
+		}
+		if len(test.reactors) != len(c.Actions()) {
+			t.Errorf("[%v]wrong number of api interactions")
+		}
+	}
+}