Merge pull request #102711 from jiahuif/feature/leader-migration/wildcard

Leader Migration: wildcard and default value

staging/src/k8s.io/controller-manager/config/types.go

@@ -77,5 +77,6 @@ type ControllerLeaderConfiguration struct {
 
 	// Component is the name of the component in which the controller should be running.
 	// E.g. kube-controller-manager, cloud-controller-manager, etc
+	// Or '*' meaning the controller can be run under any component that participates in the migration
 	Component string
 }

staging/src/k8s.io/controller-manager/config/v1alpha1/types.go

@@ -76,5 +76,6 @@ type ControllerLeaderConfiguration struct {
 
 	// Component is the name of the component in which the controller should be running.
 	// E.g. kube-controller-manager, cloud-controller-manager, etc
+	// Or '*' meaning the controller can be run under any component that participates in the migration
 	Component string `json:"component"`
 }

staging/src/k8s.io/controller-manager/pkg/leadermigration/config/default.go

@@ -0,0 +1,40 @@
+/*
+Copyright 2021 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 config
+
+import internal "k8s.io/controller-manager/config"
+
+// DefaultLeaderMigrationConfiguration returns the default LeaderMigrationConfiguration
+//  that is valid for this release of Kubernetes.
+func DefaultLeaderMigrationConfiguration() *internal.LeaderMigrationConfiguration {
+	return &internal.LeaderMigrationConfiguration{
+		LeaderName:   "cloud-provider-extraction-migration",
+		ResourceLock: ResourceLockLeases,
+		ControllerLeaders: []internal.ControllerLeaderConfiguration{
+			{
+				Name:      "route",
+				Component: "*",
+			}, {
+				Name:      "service",
+				Component: "*",
+			}, {
+				Name:      "cloud-node-lifecycle",
+				Component: "*",
+			},
+		},
+	}
+}

staging/src/k8s.io/controller-manager/pkg/leadermigration/migrator.go

@@ -36,7 +36,7 @@ type LeaderMigrator struct {
 func NewLeaderMigrator(config *internal.LeaderMigrationConfiguration, component string) *LeaderMigrator {
 	migratedControllers := make(map[string]bool)
 	for _, leader := range config.ControllerLeaders {
-		migratedControllers[leader.Name] = leader.Component == component
+		migratedControllers[leader.Name] = leader.Component == component || leader.Component == "*"
 	}
 	return &LeaderMigrator{
 		MigrationReady: make(chan struct{}),

staging/src/k8s.io/controller-manager/pkg/leadermigration/migrator_test.go

@@ -55,6 +55,22 @@ func TestLeaderMigratorFilterFunc(t *testing.T) {
 			},
 		},
 	}
+	wildcardConfig := &internal.LeaderMigrationConfiguration{
+		ResourceLock: "leases",
+		LeaderName:   "cloud-provider-extraction-migration",
+		ControllerLeaders: []internal.ControllerLeaderConfiguration{
+			{
+				Name:      "route",
+				Component: "*",
+			}, {
+				Name:      "service",
+				Component: "*",
+			}, {
+				Name:      "cloud-node-lifecycle",
+				Component: "*",
+			},
+		},
+	}
 	for _, tc := range []struct {
 		name         string
 		config       *internal.LeaderMigrationConfiguration
@@ -106,6 +122,28 @@ func TestLeaderMigratorFilterFunc(t *testing.T) {
 				"cloud-node-lifecycle": ControllerMigrated,
 			},
 		},
+		{
+			name:      "wildcard config, kcm",
+			config:    wildcardConfig,
+			component: "kube-controller-manager",
+			expectResult: map[string]FilterResult{
+				"deployment":           ControllerNonMigrated, // KCM only
+				"route":                ControllerMigrated,
+				"service":              ControllerMigrated,
+				"cloud-node-lifecycle": ControllerMigrated,
+			},
+		},
+		{
+			name:      "wildcard config, ccm",
+			config:    wildcardConfig,
+			component: "cloud-controller-manager",
+			expectResult: map[string]FilterResult{
+				"cloud-node":           ControllerNonMigrated, // CCM only
+				"route":                ControllerMigrated,
+				"service":              ControllerMigrated,
+				"cloud-node-lifecycle": ControllerMigrated,
+			},
+		},
 	} {
 		t.Run(tc.name, func(t *testing.T) {
 			migrator := NewLeaderMigrator(tc.config, tc.component)

staging/src/k8s.io/controller-manager/pkg/leadermigration/options/options.go

@@ -73,7 +73,8 @@ func (o *LeaderMigrationOptions) ApplyTo(cfg *config.GenericControllerManagerCon
 		return nil
 	}
 	if o.ControllerMigrationConfig == "" {
-		return fmt.Errorf("--leader-migration-config is required")
+		cfg.LeaderMigration = *migrationconfig.DefaultLeaderMigrationConfiguration()
+		return nil
 	}
 	leaderMigrationConfig, err := migrationconfig.ReadLeaderMigrationConfiguration(o.ControllerMigrationConfig)
 	if err != nil {

staging/src/k8s.io/controller-manager/pkg/leadermigration/options/options_test.go

@@ -27,6 +27,7 @@ import (
 	featuregatetesting "k8s.io/component-base/featuregate/testing"
 	"k8s.io/controller-manager/config"
 	"k8s.io/controller-manager/pkg/features"
+	migrationconfig "k8s.io/controller-manager/pkg/leadermigration/config"
 )
 
 func TestLeaderMigrationOptions(t *testing.T) {
@@ -53,11 +54,12 @@ func TestLeaderMigrationOptions(t *testing.T) {
 			expectErr:         true,
 		},
 		{
-			name:              "enabled, but missing configuration file",
+			name:              "enabled, with default configuration",
 			flags:             []string{"--enable-leader-migration"},
 			enableFeatureGate: true,
 			expectEnabled:     true,
-			expectErr:         true,
+			expectErr:         false,
+			expectConfig:      migrationconfig.DefaultLeaderMigrationConfiguration(),
 		},
 		{
 			name:              "enabled, with custom configuration file",