Prefactor: Move updating of APIService to a separate controller

- The certs manager controller, along with its sibling certs expirer
  and certs observer controllers, are generally useful for any process
  that wants to create its own CA and TLS certs, but only if the
  updating of the APIService is not included in those controllers
- So that functionality for updating APIServices is moved to a new
  controller which watches the same Secret which is used by those
  other controllers
- Also parameterize `NewCertsManagerController` with the service name
  and the CA common name to make the controller more reusable

go.sum

@@ -100,6 +100,7 @@ github.com/creack/pty v1.1.7/go.mod h1:lj5s0c3V2DBrqTV7llrYr5NG6My20zk30Fl46Y7Do
 github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
 github.com/daixiang0/gci v0.0.0-20200727065011-66f1df783cb2 h1:3Lhhps85OdA8ezsEKu+IA1hE+DBTjt/fjd7xNCrHbVA=
 github.com/daixiang0/gci v0.0.0-20200727065011-66f1df783cb2/go.mod h1:+AV8KmHTGxxwp/pY84TLQfFKp2vuKXXJVzF3kD/hfR4=
+github.com/daixiang0/gci v0.2.4 h1:BUCKk5nlK2m+kRIsoj+wb/5hazHvHeZieBKWd9Afa8Q=
 github.com/daixiang0/gci v0.2.4/go.mod h1:+AV8KmHTGxxwp/pY84TLQfFKp2vuKXXJVzF3kD/hfR4=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
@@ -134,6 +135,7 @@ github.com/ghodss/yaml v0.0.0-20150909031657-73d445a93680/go.mod h1:4dBDuWmgqj2H
 github.com/ghodss/yaml v1.0.0/go.mod h1:4dBDuWmgqj2HViK6kFavaiC9ZROes6MMH2rRYeMEF04=
 github.com/go-critic/go-critic v0.5.0 h1:Ic2p5UCl5fX/2WX2w8nroPpPhxRNsNTMlJzsu/uqwnM=
 github.com/go-critic/go-critic v0.5.0/go.mod h1:4jeRh3ZAVnRYhuWdOEvwzVqLUpxMSoAT0xZ74JsTPlo=
+github.com/go-critic/go-critic v0.5.2 h1:3RJdgf6u4NZUumoP8nzbqiiNT8e1tC2Oc7jlgqre/IA=
 github.com/go-critic/go-critic v0.5.2/go.mod h1:cc0+HvdE3lFpqLecgqMaJcvWWH77sLdBp+wLGPM1Yyo=
 github.com/go-gl/glfw v0.0.0-20190409004039-e6da0acd62b1/go.mod h1:vR7hzQXu2zJy9AVAgeJqvqgH9Q5CA+iKCZ2gyEVpxRU=
 github.com/go-gl/glfw/v3.3/glfw v0.0.0-20191125211704-12ad95a8df72/go.mod h1:tQ2UAYgL5IevRw8kRxooKSPJfGvJ9fJQFa0TUsXzTg8=
@@ -197,6 +199,7 @@ github.com/gobwas/glob v0.2.3 h1:A4xDbljILXROh+kObIiy5kIaPYD8e96x1tgBhUI5J+Y=
 github.com/gobwas/glob v0.2.3/go.mod h1:d3Ez4x06l9bZtSvzIay5+Yzi0fmZzPgnTbPcKjJAkT8=
 github.com/gofrs/flock v0.7.1 h1:DP+LD/t0njgoPBvT5MJLeliUIVQR03hiKR6vezdwHlc=
 github.com/gofrs/flock v0.7.1/go.mod h1:F1TvTiK9OcQqauNUHlbJvyl9Qa1QvF/gOUDKA14jxHU=
+github.com/gofrs/flock v0.8.0 h1:MSdYClljsF3PbENUUEx85nkWfJSGfzYI9yEBZOJz6CY=
 github.com/gofrs/flock v0.8.0/go.mod h1:F1TvTiK9OcQqauNUHlbJvyl9Qa1QvF/gOUDKA14jxHU=
 github.com/gogo/protobuf v1.1.1/go.mod h1:r8qH/GZQm5c6nD/R0oafs1akxWv10x8SbQlK7atdtwQ=
 github.com/gogo/protobuf v1.2.1/go.mod h1:hp+jE20tsWTFYpLwKvXlhS1hjn+gTNwPg2I6zVXpSg4=
@@ -435,6 +438,7 @@ github.com/niemeyer/pretty v0.0.0-20200227124842-a10e7caefd8e h1:fD57ERR4JtEqsWb
 github.com/niemeyer/pretty v0.0.0-20200227124842-a10e7caefd8e/go.mod h1:zD1mROLANZcx1PVRCS0qkT7pwLkGfwJo4zjcN/Tysno=
 github.com/nishanths/exhaustive v0.0.0-20200708172631-8866003e3856 h1:W3KBC2LFyfgd+wNudlfgCCsTo4q97MeNWrfz8/wSdSc=
 github.com/nishanths/exhaustive v0.0.0-20200708172631-8866003e3856/go.mod h1:wBEpHwM2OdmeNpdCvRPUlkEbBuaFmcK4Wv8Q7FuGW3c=
+github.com/nishanths/exhaustive v0.0.0-20200811152831-6cf413ae40e0 h1:eMV1t2NQRc3r1k3guWiv/zEeqZZP6kPvpUfy6byfL1g=
 github.com/nishanths/exhaustive v0.0.0-20200811152831-6cf413ae40e0/go.mod h1:wBEpHwM2OdmeNpdCvRPUlkEbBuaFmcK4Wv8Q7FuGW3c=
 github.com/nxadm/tail v1.4.4 h1:DQuhQpB1tVlglWS2hLQ5OV6B5r8aGxSrPc5Qo6uTN78=
 github.com/nxadm/tail v1.4.4/go.mod h1:kenIhsEOeOJmVchQTgglprH7qJGnHDVpk1VPCcaMI8A=
@@ -490,6 +494,7 @@ github.com/prometheus/tsdb v0.7.1/go.mod h1:qhTCs0VvXwvX/y3TZrWD7rabWM+ijKTux40T
 github.com/quasilyte/go-consistent v0.0.0-20190521200055-c6f3937de18c/go.mod h1:5STLWrekHfjyYwxBRVRXNOSewLJ3PWfDJd1VyTS21fI=
 github.com/quasilyte/go-ruleguard v0.1.2-0.20200318202121-b00d7a75d3d8 h1:DvnesvLtRPQOvaUbfXfh0tpMHg29by0H7F2U+QIkSu8=
 github.com/quasilyte/go-ruleguard v0.1.2-0.20200318202121-b00d7a75d3d8/go.mod h1:CGFX09Ci3pq9QZdj86B+VGIdNj4VyCo2iPOGS9esB/k=
+github.com/quasilyte/go-ruleguard v0.2.0 h1:UOVMyH2EKkxIfzrULvA9n/tO+HtEhqD9mrLSWMr5FwU=
 github.com/quasilyte/go-ruleguard v0.2.0/go.mod h1:2RT/tf0Ce0UDj5y243iWKosQogJd8+1G3Rs2fxmlYnw=
 github.com/quasilyte/regex/syntax v0.0.0-20200407221936-30656e2c4a95 h1:L8QM9bvf68pVdQ3bCFZMDmnt9yqcMBro1pC7F+IPYMY=
 github.com/quasilyte/regex/syntax v0.0.0-20200407221936-30656e2c4a95/go.mod h1:rlzQ04UMyJXu/aOvhd8qT+hvDrFpiwqp8MRXDY9szc0=
@@ -531,6 +536,7 @@ github.com/sonatard/noctx v0.0.1 h1:VC1Qhl6Oxx9vvWo3UDgrGXYCeKCe3Wbw7qAWL6FrmTY=
 github.com/sonatard/noctx v0.0.1/go.mod h1:9D2D/EoULe8Yy2joDHJj7bv3sZoq9AaSb8B4lqBjiZI=
 github.com/sourcegraph/go-diff v0.5.3 h1:lhIKJ2nXLZZ+AfbHpYxTn0pXpNTTui0DX7DO3xeb1Zs=
 github.com/sourcegraph/go-diff v0.5.3/go.mod h1:v9JDtjCE4HHHCZGId75rg8gkKKa98RVjBcBGsVmMmak=
+github.com/sourcegraph/go-diff v0.6.0 h1:WbN9e/jD8ujU+o0vd9IFN5AEwtfB0rn/zM/AANaClqQ=
 github.com/sourcegraph/go-diff v0.6.0/go.mod h1:iBszgVvyxdc8SFZ7gm69go2KDdt3ag071iBaWPF6cjs=
 github.com/spaolacci/murmur3 v0.0.0-20180118202830-f09979ecbc72/go.mod h1:JwIasOWyU6f++ZhiEuf87xNszmSA2myDM2Kzu9HwQUA=
 github.com/spf13/afero v1.1.2/go.mod h1:j4pytiNVoe2o6bmDsKpLACNPDBIoEAkihy7loJ1B0CQ=
@@ -551,9 +557,11 @@ github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An
 github.com/spf13/viper v1.4.0/go.mod h1:PTJ7Z/lr49W6bUbkmS1V3by4uWynFiR9p7+dSq/yZzE=
 github.com/spf13/viper v1.7.0 h1:xVKxvI7ouOI5I+U9s2eeiUfMaWBVoXA3AWskkrqK0VM=
 github.com/spf13/viper v1.7.0/go.mod h1:8WkrPz2fc9jxqZNCJI/76HCieCp4Q8HaLFoCha5qpdg=
+github.com/spf13/viper v1.7.1 h1:pM5oEahlgWv/WnHXpgbKz7iLIxRf65tye2Ci+XFK5sk=
 github.com/spf13/viper v1.7.1/go.mod h1:8WkrPz2fc9jxqZNCJI/76HCieCp4Q8HaLFoCha5qpdg=
 github.com/ssgreg/nlreturn/v2 v2.0.1 h1:+lm6xFjVuNw/9t/Fh5sIwfNWefiD5bddzc6vwJ1TvRI=
 github.com/ssgreg/nlreturn/v2 v2.0.1/go.mod h1:E/iiPB78hV7Szg2YfRgyIrk1AD6JVMTRkkxBiELzh2I=
+github.com/ssgreg/nlreturn/v2 v2.1.0 h1:6/s4Rc49L6Uo6RLjhWZGBpWWjfzk2yrf1nIW8m4wgVA=
 github.com/ssgreg/nlreturn/v2 v2.1.0/go.mod h1:E/iiPB78hV7Szg2YfRgyIrk1AD6JVMTRkkxBiELzh2I=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/objx v0.1.1/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
@@ -581,6 +589,7 @@ github.com/tommy-muehle/go-mnd v1.3.1-0.20200224220436-e6f9a994e8fa/go.mod h1:dS
 github.com/ugorji/go v1.1.4/go.mod h1:uQMGLiO92mf5W77hV/PUCpI3pbzQx3CRekS0kk+RGrc=
 github.com/ultraware/funlen v0.0.2 h1:Av96YVBwwNSe4MLR7iI/BIa3VyI7/djnto/pK3Uxbdo=
 github.com/ultraware/funlen v0.0.2/go.mod h1:Dp4UiAus7Wdb9KUZsYWZEWiRzGuM2kXM1lPbfaF6xhA=
+github.com/ultraware/funlen v0.0.3 h1:5ylVWm8wsNwH5aWo9438pwvsK0QiqVuUrt9bn7S/iLA=
 github.com/ultraware/funlen v0.0.3/go.mod h1:Dp4UiAus7Wdb9KUZsYWZEWiRzGuM2kXM1lPbfaF6xhA=
 github.com/ultraware/whitespace v0.0.4 h1:If7Va4cM03mpgrNH9k49/VOicWpGoG70XPBFFODYDsg=
 github.com/ultraware/whitespace v0.0.4/go.mod h1:aVMh/gQve5Maj9hQ/hg+F75lr/X5A89uZnzAmWSineA=
@@ -784,11 +793,13 @@ golang.org/x/tools v0.0.0-20200626171337-aa94e735be7f/go.mod h1:EkVYQZoAsY45+roY
 golang.org/x/tools v0.0.0-20200701041122-1837592efa10/go.mod h1:EkVYQZoAsY45+roYkvgYkIh4xh/qjgUK9TdY2XT94GE=
 golang.org/x/tools v0.0.0-20200724022722-7017fd6b1305 h1:yaM5S0KcY0lIoZo7Fl+oi91b/DdlU2zuWpfHrpWbCS0=
 golang.org/x/tools v0.0.0-20200724022722-7017fd6b1305/go.mod h1:njjCfa9FT2d7l9Bc6FUM5FLjQPp3cFF28FI3qnDFljA=
+golang.org/x/tools v0.0.0-20200812195022-5ae4c3c160a0 h1:SQvH+DjrwqD1hyyQU+K7JegHz1KEZgEwt17p9d6R2eg=
 golang.org/x/tools v0.0.0-20200812195022-5ae4c3c160a0/go.mod h1:njjCfa9FT2d7l9Bc6FUM5FLjQPp3cFF28FI3qnDFljA=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543 h1:E7g+9GITq07hpfrRu66IVDexMakfv52eLZ2CXBWiKr4=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 h1:go1bK/D/BFZV2I8cIQd1NKEZ+0owSTG1fDTci4IqFcE=
 golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 google.golang.org/api v0.4.0/go.mod h1:8k5glujaEP+g9n7WNsDg8QP6cUVNI86fCNMcbazEtwE=
 google.golang.org/api v0.7.0/go.mod h1:WtwebWUNSVBH/HAw79HIFXZNqEvBhG+Ra+ax0hx3E3M=
@@ -872,6 +883,7 @@ honnef.co/go/tools v0.0.0-20190523083050-ea95bdfd59fc/go.mod h1:rf3lG4BRIbNafJWh
 honnef.co/go/tools v0.0.1-2019.2.3/go.mod h1:a3bituU0lyd329TUQxRnasdCoJDkEUEAqEt0JzvZhAg=
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+honnef.co/go/tools v0.0.1-2020.1.5 h1:nI5egYTGJakVyOryqLs1cQO5dO0ksin5XXs2pspk75k=
 honnef.co/go/tools v0.0.1-2020.1.5/go.mod h1:X/FiERA/W4tHapMX5mGpAtMSVEeEUOyHaw9vFzvIQ3k=
 k8s.io/api v0.19.0 h1:XyrFIJqTYZJ2DU7FBE/bSPz7b1HvbVBuBf07oeo6eTc=
 k8s.io/api v0.19.0/go.mod h1:I1K45XlvTrDjmj5LoM5LuP/KYrhWbjUKT/SoPG0qTjw=

internal/controller/apicerts/apiservice_updater.go

@@ -0,0 +1,69 @@
+/*
+Copyright 2020 VMware, Inc.
+SPDX-License-Identifier: Apache-2.0
+*/
+
+package apicerts
+
+import (
+	"fmt"
+
+	k8serrors "k8s.io/apimachinery/pkg/api/errors"
+	corev1informers "k8s.io/client-go/informers/core/v1"
+	"k8s.io/klog/v2"
+	aggregatorclient "k8s.io/kube-aggregator/pkg/client/clientset_generated/clientset"
+
+	pinnipedcontroller "github.com/suzerain-io/pinniped/internal/controller"
+	"github.com/suzerain-io/pinniped/internal/controllerlib"
+)
+
+type apiServiceUpdaterController struct {
+	namespace        string
+	aggregatorClient aggregatorclient.Interface
+	secretInformer   corev1informers.SecretInformer
+}
+
+func NewAPIServiceUpdaterController(
+	namespace string,
+	aggregatorClient aggregatorclient.Interface,
+	secretInformer corev1informers.SecretInformer,
+	withInformer pinnipedcontroller.WithInformerOptionFunc,
+) controllerlib.Controller {
+	return controllerlib.New(
+		controllerlib.Config{
+			Name: "certs-manager-controller",
+			Syncer: &apiServiceUpdaterController{
+				namespace:        namespace,
+				aggregatorClient: aggregatorClient,
+				secretInformer:   secretInformer,
+			},
+		},
+		withInformer(
+			secretInformer,
+			pinnipedcontroller.NameAndNamespaceExactMatchFilterFactory(certsSecretName, namespace),
+			controllerlib.InformerOption{},
+		),
+	)
+}
+
+func (c *apiServiceUpdaterController) Sync(ctx controllerlib.Context) error {
+	// Try to get the secret from the informer cache.
+	certSecret, err := c.secretInformer.Lister().Secrets(c.namespace).Get(certsSecretName)
+	notFound := k8serrors.IsNotFound(err)
+	if err != nil && !notFound {
+		return fmt.Errorf("failed to get %s/%s secret: %w", c.namespace, certsSecretName, err)
+	}
+	if notFound {
+		// The secret does not exist yet, so nothing to do.
+		klog.Info("apiServiceUpdaterController Sync found that the secret does not exist yet or was deleted")
+		return nil
+	}
+
+	// Update the APIService to give it the new CA bundle.
+	if err := UpdateAPIService(ctx.Context, c.aggregatorClient, certSecret.Data[caCertificateSecretKey]); err != nil {
+		return fmt.Errorf("could not update the API service: %w", err)
+	}
+
+	klog.Info("apiServiceUpdaterController Sync successfully updated API service")
+	return nil
+}

internal/controller/apicerts/apiservice_updater_test.go

@@ -0,0 +1,277 @@
+/*
+Copyright 2020 VMware, Inc.
+SPDX-License-Identifier: Apache-2.0
+*/
+
+package apicerts
+
+import (
+	"context"
+	"errors"
+	"testing"
+	"time"
+
+	"github.com/sclevine/spec"
+	"github.com/sclevine/spec/report"
+	"github.com/stretchr/testify/require"
+	corev1 "k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	kubeinformers "k8s.io/client-go/informers"
+	kubernetesfake "k8s.io/client-go/kubernetes/fake"
+	coretesting "k8s.io/client-go/testing"
+	apiregistrationv1 "k8s.io/kube-aggregator/pkg/apis/apiregistration/v1"
+	aggregatorfake "k8s.io/kube-aggregator/pkg/client/clientset_generated/clientset/fake"
+
+	pinnipedv1alpha1 "github.com/suzerain-io/pinniped/generated/1.19/apis/pinniped/v1alpha1"
+	"github.com/suzerain-io/pinniped/internal/controllerlib"
+	"github.com/suzerain-io/pinniped/internal/testutil"
+)
+
+func TestAPIServiceUpdaterControllerOptions(t *testing.T) {
+	spec.Run(t, "options", func(t *testing.T, when spec.G, it spec.S) {
+		const installedInNamespace = "some-namespace"
+
+		var r *require.Assertions
+		var observableWithInformerOption *testutil.ObservableWithInformerOption
+		var secretsInformerFilter controllerlib.Filter
+
+		it.Before(func() {
+			r = require.New(t)
+			observableWithInformerOption = testutil.NewObservableWithInformerOption()
+			secretsInformer := kubeinformers.NewSharedInformerFactory(nil, 0).Core().V1().Secrets()
+			_ = NewAPIServiceUpdaterController(
+				installedInNamespace,
+				nil,
+				secretsInformer,
+				observableWithInformerOption.WithInformer, // make it possible to observe the behavior of the Filters
+			)
+			secretsInformerFilter = observableWithInformerOption.GetFilterForInformer(secretsInformer)
+		})
+
+		when("watching Secret objects", func() {
+			var subject controllerlib.Filter
+			var target, wrongNamespace, wrongName, unrelated *corev1.Secret
+
+			it.Before(func() {
+				subject = secretsInformerFilter
+				target = &corev1.Secret{ObjectMeta: metav1.ObjectMeta{Name: "api-serving-cert", Namespace: installedInNamespace}}
+				wrongNamespace = &corev1.Secret{ObjectMeta: metav1.ObjectMeta{Name: "api-serving-cert", Namespace: "wrong-namespace"}}
+				wrongName = &corev1.Secret{ObjectMeta: metav1.ObjectMeta{Name: "wrong-name", Namespace: installedInNamespace}}
+				unrelated = &corev1.Secret{ObjectMeta: metav1.ObjectMeta{Name: "wrong-name", Namespace: "wrong-namespace"}}
+			})
+
+			when("the target Secret changes", func() {
+				it("returns true to trigger the sync method", func() {
+					r.True(subject.Add(target))
+					r.True(subject.Update(target, unrelated))
+					r.True(subject.Update(unrelated, target))
+					r.True(subject.Delete(target))
+				})
+			})
+
+			when("a Secret from another namespace changes", func() {
+				it("returns false to avoid triggering the sync method", func() {
+					r.False(subject.Add(wrongNamespace))
+					r.False(subject.Update(wrongNamespace, unrelated))
+					r.False(subject.Update(unrelated, wrongNamespace))
+					r.False(subject.Delete(wrongNamespace))
+				})
+			})
+
+			when("a Secret with a different name changes", func() {
+				it("returns false to avoid triggering the sync method", func() {
+					r.False(subject.Add(wrongName))
+					r.False(subject.Update(wrongName, unrelated))
+					r.False(subject.Update(unrelated, wrongName))
+					r.False(subject.Delete(wrongName))
+				})
+			})
+
+			when("a Secret with a different name and a different namespace changes", func() {
+				it("returns false to avoid triggering the sync method", func() {
+					r.False(subject.Add(unrelated))
+					r.False(subject.Update(unrelated, unrelated))
+					r.False(subject.Delete(unrelated))
+				})
+			})
+		})
+	}, spec.Parallel(), spec.Report(report.Terminal{}))
+}
+
+func TestAPIServiceUpdaterControllerSync(t *testing.T) {
+	spec.Run(t, "Sync", func(t *testing.T, when spec.G, it spec.S) {
+		const installedInNamespace = "some-namespace"
+
+		var r *require.Assertions
+
+		var subject controllerlib.Controller
+		var aggregatorAPIClient *aggregatorfake.Clientset
+		var kubeInformerClient *kubernetesfake.Clientset
+		var kubeInformers kubeinformers.SharedInformerFactory
+		var timeoutContext context.Context
+		var timeoutContextCancel context.CancelFunc
+		var syncContext *controllerlib.Context
+
+		// Defer starting the informers until the last possible moment so that the
+		// nested Before's can keep adding things to the informer caches.
+		var startInformersAndController = func() {
+			// Set this at the last second to allow for injection of server override.
+			subject = NewAPIServiceUpdaterController(
+				installedInNamespace,
+				aggregatorAPIClient,
+				kubeInformers.Core().V1().Secrets(),
+				controllerlib.WithInformer,
+			)
+
+			// Set this at the last second to support calling subject.Name().
+			syncContext = &controllerlib.Context{
+				Context: timeoutContext,
+				Name:    subject.Name(),
+				Key: controllerlib.Key{
+					Namespace: installedInNamespace,
+					Name:      "api-serving-cert",
+				},
+			}
+
+			// Must start informers before calling TestRunSynchronously()
+			kubeInformers.Start(timeoutContext.Done())
+			controllerlib.TestRunSynchronously(t, subject)
+		}
+
+		it.Before(func() {
+			r = require.New(t)
+
+			timeoutContext, timeoutContextCancel = context.WithTimeout(context.Background(), time.Second*3)
+
+			kubeInformerClient = kubernetesfake.NewSimpleClientset()
+			kubeInformers = kubeinformers.NewSharedInformerFactory(kubeInformerClient, 0)
+			aggregatorAPIClient = aggregatorfake.NewSimpleClientset()
+		})
+
+		it.After(func() {
+			timeoutContextCancel()
+		})
+
+		when("there is not yet an api-serving-cert Secret in the installation namespace or it was deleted", func() {
+			it.Before(func() {
+				unrelatedSecret := &corev1.Secret{
+					ObjectMeta: metav1.ObjectMeta{
+						Name:      "some other secret",
+						Namespace: installedInNamespace,
+					},
+				}
+				err := kubeInformerClient.Tracker().Add(unrelatedSecret)
+				r.NoError(err)
+			})
+
+			it("does not need to make any API calls with its API client", func() {
+				startInformersAndController()
+				err := controllerlib.TestSync(t, subject, *syncContext)
+				r.NoError(err)
+				r.Empty(aggregatorAPIClient.Actions())
+			})
+		})
+
+		when("there is an api-serving-cert Secret already in the installation namespace", func() {
+			it.Before(func() {
+				apiServingCertSecret := &corev1.Secret{
+					ObjectMeta: metav1.ObjectMeta{
+						Name:      "api-serving-cert",
+						Namespace: installedInNamespace,
+					},
+					Data: map[string][]byte{
+						"caCertificate":       []byte("fake CA cert"),
+						"tlsPrivateKey":       []byte("fake private key"),
+						"tlsCertificateChain": []byte("fake cert chain"),
+					},
+				}
+				err := kubeInformerClient.Tracker().Add(apiServingCertSecret)
+				r.NoError(err)
+			})
+
+			when("the APIService exists", func() {
+				it.Before(func() {
+					apiService := &apiregistrationv1.APIService{
+						ObjectMeta: metav1.ObjectMeta{
+							Name: pinnipedv1alpha1.SchemeGroupVersion.Version + "." + pinnipedv1alpha1.GroupName,
+						},
+						Spec: apiregistrationv1.APIServiceSpec{
+							CABundle:        nil,
+							VersionPriority: 1234,
+						},
+					}
+					err := aggregatorAPIClient.Tracker().Add(apiService)
+					r.NoError(err)
+				})
+
+				it("updates the APIService's ca bundle", func() {
+					startInformersAndController()
+					err := controllerlib.TestSync(t, subject, *syncContext)
+					r.NoError(err)
+
+					// Make sure we updated the APIService caBundle and left it otherwise unchanged
+					r.Len(aggregatorAPIClient.Actions(), 2)
+					r.Equal("get", aggregatorAPIClient.Actions()[0].GetVerb())
+					expectedAPIServiceName := pinnipedv1alpha1.SchemeGroupVersion.Version + "." + pinnipedv1alpha1.GroupName
+					expectedUpdateAction := coretesting.NewUpdateAction(
+						schema.GroupVersionResource{
+							Group:    apiregistrationv1.GroupName,
+							Version:  "v1",
+							Resource: "apiservices",
+						},
+						"",
+						&apiregistrationv1.APIService{
+							ObjectMeta: metav1.ObjectMeta{
+								Name:      expectedAPIServiceName,
+								Namespace: "",
+							},
+							Spec: apiregistrationv1.APIServiceSpec{
+								VersionPriority: 1234, // only the CABundle is updated, this other field is left unchanged
+								CABundle:        []byte("fake CA cert"),
+							},
+						},
+					)
+					r.Equal(expectedUpdateAction, aggregatorAPIClient.Actions()[1])
+				})
+
+				when("updating the APIService fails", func() {
+					it.Before(func() {
+						aggregatorAPIClient.PrependReactor(
+							"update",
+							"apiservices",
+							func(_ coretesting.Action) (bool, runtime.Object, error) {
+								return true, nil, errors.New("update failed")
+							},
+						)
+					})
+
+					it("returns the update error", func() {
+						startInformersAndController()
+						err := controllerlib.TestSync(t, subject, *syncContext)
+						r.EqualError(err, "could not update the API service: could not update API service: update failed")
+					})
+				})
+			})
+
+			when("the APIService does not exist", func() {
+				it.Before(func() {
+					unrelatedAPIService := &apiregistrationv1.APIService{
+						ObjectMeta: metav1.ObjectMeta{Name: "some other api service"},
+						Spec:       apiregistrationv1.APIServiceSpec{},
+					}
+					err := aggregatorAPIClient.Tracker().Add(unrelatedAPIService)
+					r.NoError(err)
+				})
+
+				it("returns an error", func() {
+					startInformersAndController()
+					err := controllerlib.TestSync(t, subject, *syncContext)
+					r.Error(err)
+					r.Regexp("could not get existing version of API service: .* not found", err.Error())
+				})
+			})
+		})
+	}, spec.Parallel(), spec.Report(report.Terminal{}))
+}

internal/controller/apicerts/certs_expirer.go

@@ -69,7 +69,7 @@ func (c *certsExpirerController) Sync(ctx controllerlib.Context) error {
 		return fmt.Errorf("failed to get %s/%s secret: %w", c.namespace, certsSecretName, err)
 	}
 	if notFound {
-		klog.Info("certsExpirerController Sync() found that the secret does not exist yet or was deleted")
+		klog.Info("certsExpirerController Sync found that the secret does not exist yet or was deleted")
 		return nil
 	}
 
@@ -78,13 +78,13 @@ func (c *certsExpirerController) Sync(ctx controllerlib.Context) error {
 		// If we can't read the cert, then really all we can do is log something,
 		// since if we returned an error then the controller lib would just call us
 		// again and again, which would probably yield the same results.
-		klog.Warningf("certsExpirerController Sync() found that the secret is malformed: %s", err.Error())
+		klog.Warningf("certsExpirerController Sync found that the secret is malformed: %s", err.Error())
 		return nil
 	}
 
 	certAge := time.Since(notBefore)
 	renewDelta := certAge - c.renewBefore
-	klog.Infof("certsExpirerController Sync() found a renew delta of %s", renewDelta)
+	klog.Infof("certsExpirerController Sync found a renew delta of %s", renewDelta)
 	if renewDelta >= 0 || time.Now().After(notAfter) {
 		err := c.k8sClient.
 			CoreV1().

internal/controller/apicerts/certs_manager.go

@@ -16,7 +16,6 @@ import (
 	corev1informers "k8s.io/client-go/informers/core/v1"
 	"k8s.io/client-go/kubernetes"
 	"k8s.io/klog/v2"
-	aggregatorclient "k8s.io/kube-aggregator/pkg/client/clientset_generated/clientset"
 
 	"github.com/suzerain-io/pinniped/internal/certauthority"
 	pinnipedcontroller "github.com/suzerain-io/pinniped/internal/controller"
@@ -34,22 +33,24 @@ const (
 type certsManagerController struct {
 	namespace      string
 	k8sClient      kubernetes.Interface
-	aggregatorClient aggregatorclient.Interface
 	secretInformer corev1informers.SecretInformer
 
 	// certDuration is the lifetime of both the serving certificate and its CA
 	// certificate that this controller will use when issuing the certificates.
 	certDuration time.Duration
+
+	generatedCACommonName                 string
+	serviceNameForGeneratedCertCommonName string
 }
 
-func NewCertsManagerController(
+func NewCertsManagerController(namespace string,
-	namespace string,
 	k8sClient kubernetes.Interface,
-	aggregatorClient aggregatorclient.Interface,
 	secretInformer corev1informers.SecretInformer,
 	withInformer pinnipedcontroller.WithInformerOptionFunc,
 	withInitialEvent pinnipedcontroller.WithInitialEventOptionFunc,
 	certDuration time.Duration,
+	generatedCACommonName string,
+	serviceNameForGeneratedCertCommonName string,
 ) controllerlib.Controller {
 	return controllerlib.New(
 		controllerlib.Config{
@@ -57,9 +58,10 @@ func NewCertsManagerController(
 			Syncer: &certsManagerController{
 				namespace:                             namespace,
 				k8sClient:                             k8sClient,
-				aggregatorClient: aggregatorClient,
 				secretInformer:                        secretInformer,
 				certDuration:                          certDuration,
+				generatedCACommonName:                 generatedCACommonName,
+				serviceNameForGeneratedCertCommonName: serviceNameForGeneratedCertCommonName,
 			},
 		},
 		withInformer(
@@ -88,16 +90,13 @@ func (c *certsManagerController) Sync(ctx controllerlib.Context) error {
 	}
 
 	// Create a CA.
-	aggregatedAPIServerCA, err := certauthority.New(pkix.Name{CommonName: "Pinniped CA"}, c.certDuration)
+	aggregatedAPIServerCA, err := certauthority.New(pkix.Name{CommonName: c.generatedCACommonName}, c.certDuration)
 	if err != nil {
 		return fmt.Errorf("could not initialize CA: %w", err)
 	}
 
-	// This string must match the name of the Service declared in the deployment yaml.
-	const serviceName = "pinniped-api"
-
 	// Using the CA from above, create a TLS server cert for the aggregated API server to use.
-	serviceEndpoint := serviceName + "." + c.namespace + ".svc"
+	serviceEndpoint := c.serviceNameForGeneratedCertCommonName + "." + c.namespace + ".svc"
 	aggregatedAPIServerTLSCert, err := aggregatedAPIServerCA.Issue(
 		pkix.Name{CommonName: serviceEndpoint},
 		[]string{serviceEndpoint},
@@ -129,11 +128,6 @@ func (c *certsManagerController) Sync(ctx controllerlib.Context) error {
 		return fmt.Errorf("could not create secret: %w", err)
 	}
 
-	// Update the APIService to give it the new CA bundle.
+	klog.Info("certsManagerController Sync successfully created secret")
-	if err := UpdateAPIService(ctx.Context, c.aggregatorClient, aggregatedAPIServerCA.Bundle()); err != nil {
-		return fmt.Errorf("could not update the API service: %w", err)
-	}
-
-	klog.Info("certsManagerController Sync successfully created secret and updated API service")
 	return nil
 }

internal/controller/apicerts/certs_manager_test.go

@@ -21,10 +21,7 @@ import (
 	kubeinformers "k8s.io/client-go/informers"
 	kubernetesfake "k8s.io/client-go/kubernetes/fake"
 	coretesting "k8s.io/client-go/testing"
-	apiregistrationv1 "k8s.io/kube-aggregator/pkg/apis/apiregistration/v1"
-	aggregatorfake "k8s.io/kube-aggregator/pkg/client/clientset_generated/clientset/fake"
 
-	pinnipedv1alpha1 "github.com/suzerain-io/pinniped/generated/1.19/apis/pinniped/v1alpha1"
 	"github.com/suzerain-io/pinniped/internal/controllerlib"
 	"github.com/suzerain-io/pinniped/internal/testutil"
 )
@@ -43,15 +40,7 @@ func TestManagerControllerOptions(t *testing.T) {
 			observableWithInformerOption = testutil.NewObservableWithInformerOption()
 			observableWithInitialEventOption = testutil.NewObservableWithInitialEventOption()
 			secretsInformer := kubeinformers.NewSharedInformerFactory(nil, 0).Core().V1().Secrets()
-			_ = NewCertsManagerController(
+			_ = NewCertsManagerController(installedInNamespace, nil, secretsInformer, observableWithInformerOption.WithInformer, observableWithInitialEventOption.WithInitialEvent, 0, "Pinniped CA", "pinniped-api")
-				installedInNamespace,
-				nil,
-				nil,
-				secretsInformer,
-				observableWithInformerOption.WithInformer,         // make it possible to observe the behavior of the Filters
-				observableWithInitialEventOption.WithInitialEvent, // make it possible to observe the behavior of the initial event
-				0, // certDuration, not needed for this test
-			)
 			secretsInformerFilter = observableWithInformerOption.GetFilterForInformer(secretsInformer)
 		})
 
@@ -123,7 +112,6 @@ func TestManagerControllerSync(t *testing.T) {
 
 		var subject controllerlib.Controller
 		var kubeAPIClient *kubernetesfake.Clientset
-		var aggregatorAPIClient *aggregatorfake.Clientset
 		var kubeInformerClient *kubernetesfake.Clientset
 		var kubeInformers kubeinformers.SharedInformerFactory
 		var timeoutContext context.Context
@@ -137,11 +125,12 @@ func TestManagerControllerSync(t *testing.T) {
 			subject = NewCertsManagerController(
 				installedInNamespace,
 				kubeAPIClient,
-				aggregatorAPIClient,
 				kubeInformers.Core().V1().Secrets(),
 				controllerlib.WithInformer,
 				controllerlib.WithInitialEvent,
 				certDuration,
+				"Pinniped CA",
+				"pinniped-api",
 			)
 
 			// Set this at the last second to support calling subject.Name().
@@ -167,7 +156,6 @@ func TestManagerControllerSync(t *testing.T) {
 			kubeInformerClient = kubernetesfake.NewSimpleClientset()
 			kubeInformers = kubeinformers.NewSharedInformerFactory(kubeInformerClient, 0)
 			kubeAPIClient = kubernetesfake.NewSimpleClientset()
-			aggregatorAPIClient = aggregatorfake.NewSimpleClientset()
 		})
 
 		it.After(func() {
@@ -186,22 +174,7 @@ func TestManagerControllerSync(t *testing.T) {
 				r.NoError(err)
 			})
 
-			when("the APIService exists", func() {
+			it("creates the api-serving-cert Secret", func() {
-				it.Before(func() {
-					apiService := &apiregistrationv1.APIService{
-						ObjectMeta: metav1.ObjectMeta{
-							Name: pinnipedv1alpha1.SchemeGroupVersion.Version + "." + pinnipedv1alpha1.GroupName,
-						},
-						Spec: apiregistrationv1.APIServiceSpec{
-							CABundle:        nil,
-							VersionPriority: 1234,
-						},
-					}
-					err := aggregatorAPIClient.Tracker().Add(apiService)
-					r.NoError(err)
-				})
-
-				it("creates the api-serving-cert Secret and updates the APIService's ca bundle", func() {
 				startInformersAndController()
 				err := controllerlib.TestSync(t, subject, *syncContext)
 				r.NoError(err)
@@ -230,67 +203,6 @@ func TestManagerControllerSync(t *testing.T) {
 				validCert.RequireDNSName("pinniped-api." + installedInNamespace + ".svc")
 				validCert.RequireLifetime(time.Now(), time.Now().Add(certDuration), 6*time.Minute)
 				validCert.RequireMatchesPrivateKey(actualPrivateKey)
-
-					// Make sure we updated the APIService caBundle and left it otherwise unchanged
-					r.Len(aggregatorAPIClient.Actions(), 2)
-					r.Equal("get", aggregatorAPIClient.Actions()[0].GetVerb())
-					expectedAPIServiceName := pinnipedv1alpha1.SchemeGroupVersion.Version + "." + pinnipedv1alpha1.GroupName
-					expectedUpdateAction := coretesting.NewUpdateAction(
-						schema.GroupVersionResource{
-							Group:    apiregistrationv1.GroupName,
-							Version:  "v1",
-							Resource: "apiservices",
-						},
-						"",
-						&apiregistrationv1.APIService{
-							ObjectMeta: metav1.ObjectMeta{
-								Name:      expectedAPIServiceName,
-								Namespace: "",
-							},
-							Spec: apiregistrationv1.APIServiceSpec{
-								VersionPriority: 1234, // only the CABundle is updated, this other field is left unchanged
-								CABundle:        []byte(actualCACert),
-							},
-						},
-					)
-					r.Equal(expectedUpdateAction, aggregatorAPIClient.Actions()[1])
-				})
-
-				when("updating the APIService fails", func() {
-					it.Before(func() {
-						aggregatorAPIClient.PrependReactor(
-							"update",
-							"apiservices",
-							func(_ coretesting.Action) (bool, runtime.Object, error) {
-								return true, nil, errors.New("update failed")
-							},
-						)
-					})
-
-					it("returns the update error", func() {
-						startInformersAndController()
-						err := controllerlib.TestSync(t, subject, *syncContext)
-						r.EqualError(err, "could not update the API service: could not update API service: update failed")
-					})
-				})
-			})
-
-			when("the APIService does not exist", func() {
-				it.Before(func() {
-					unrelatedAPIService := &apiregistrationv1.APIService{
-						ObjectMeta: metav1.ObjectMeta{Name: "some other api service"},
-						Spec:       apiregistrationv1.APIServiceSpec{},
-					}
-					err := aggregatorAPIClient.Tracker().Add(unrelatedAPIService)
-					r.NoError(err)
-				})
-
-				it("returns an error", func() {
-					startInformersAndController()
-					err := controllerlib.TestSync(t, subject, *syncContext)
-					r.Error(err)
-					r.Regexp("could not get existing version of API service: .* not found", err.Error())
-				})
 			})
 
 			when("creating the Secret fails", func() {
@@ -304,11 +216,10 @@ func TestManagerControllerSync(t *testing.T) {
 					)
 				})
 
-				it("returns the create error and does not update the APIService", func() {
+				it("returns the create error", func() {
 					startInformersAndController()
 					err := controllerlib.TestSync(t, subject, *syncContext)
 					r.EqualError(err, "could not create secret: create failed")
-					r.Empty(aggregatorAPIClient.Actions())
 				})
 			})
 		})
@@ -325,12 +236,11 @@ func TestManagerControllerSync(t *testing.T) {
 				r.NoError(err)
 			})
 
-			it("does not need to make any API calls with its API clients", func() {
+			it("does not need to make any API calls with its API client", func() {
 				startInformersAndController()
 				err := controllerlib.TestSync(t, subject, *syncContext)
 				r.NoError(err)
 				r.Empty(kubeAPIClient.Actions())
-				r.Empty(aggregatorAPIClient.Actions())
 			})
 		})
 	}, spec.Parallel(), spec.Report(report.Terminal{}))

internal/controller/apicerts/certs_observer.go

@@ -54,7 +54,7 @@ func (c *certsObserverController) Sync(_ controllerlib.Context) error {
 		return fmt.Errorf("failed to get %s/%s secret: %w", c.namespace, certsSecretName, err)
 	}
 	if notFound {
-		klog.Info("certsObserverController Sync() found that the secret does not exist yet or was deleted")
+		klog.Info("certsObserverController Sync found that the secret does not exist yet or was deleted")
 		// The secret does not exist yet or was deleted.
 		c.dynamicCertProvider.Set(nil, nil)
 		return nil

internal/controller/apicerts/update_api_service.go

@@ -6,6 +6,7 @@ SPDX-License-Identifier: Apache-2.0
 package apicerts
 
 import (
+	"bytes"
 	"context"
 	"fmt"
 
@@ -28,6 +29,11 @@ func UpdateAPIService(ctx context.Context, aggregatorClient aggregatorclient.Int
 			return fmt.Errorf("could not get existing version of API service: %w", err)
 		}
 
+		if bytes.Equal(fetchedAPIService.Spec.CABundle, aggregatedAPIServerCA) {
+			// Already has the same value, perhaps because another process already updated the object, so no need to update.
+			return nil
+		}
+
 		// Update just the field we care about.
 		fetchedAPIService.Spec.CABundle = aggregatedAPIServerCA
 

internal/controller/apicerts/update_api_service_test.go

@@ -70,17 +70,44 @@ func TestUpdateAPIService(t *testing.T) {
 				},
 			}},
 		},
+		{
+			name: "happy path update when the pre-existing APIService already has the same CA bundle so there is no need to update",
+			mocks: func(c *aggregatorv1fake.Clientset) {
+				_ = c.Tracker().Add(&apiregistrationv1.APIService{
+					ObjectMeta: metav1.ObjectMeta{Name: apiServiceName},
+					Spec: apiregistrationv1.APIServiceSpec{
+						GroupPriorityMinimum: 999,
+						CABundle:             []byte("some-ca-bundle"),
+					},
+				})
+				c.PrependReactor("update", "apiservices", func(_ kubetesting.Action) (bool, runtime.Object, error) {
+					return true, nil, fmt.Errorf("should not encounter this error because update should be skipped in this case")
+				})
+			},
+			caInput: []byte("some-ca-bundle"),
+			wantObjects: []apiregistrationv1.APIService{{
+				ObjectMeta: metav1.ObjectMeta{Name: apiServiceName},
+				Spec: apiregistrationv1.APIServiceSpec{
+					GroupPriorityMinimum: 999,
+					CABundle:             []byte("some-ca-bundle"), // unchanged
+				},
+			}},
+		},
 		{
 			name: "error on update",
 			mocks: func(c *aggregatorv1fake.Clientset) {
 				_ = c.Tracker().Add(&apiregistrationv1.APIService{
 					ObjectMeta: metav1.ObjectMeta{Name: apiServiceName},
-					Spec:       apiregistrationv1.APIServiceSpec{},
+					Spec: apiregistrationv1.APIServiceSpec{
+						GroupPriorityMinimum: 999,
+						CABundle:             []byte("some-other-different-ca-bundle"),
+					},
 				})
 				c.PrependReactor("update", "apiservices", func(_ kubetesting.Action) (bool, runtime.Object, error) {
 					return true, nil, fmt.Errorf("error on update")
 				})
 			},
+			caInput: []byte("some-ca-bundle"),
 			wantErr: "could not update API service: error on update",
 		},
 		{
@@ -143,6 +170,7 @@ func TestUpdateAPIService(t *testing.T) {
 			}},
 		},
 	}
+
 	for _, tt := range tests {
 		tt := tt
 		t.Run(tt.name, func(t *testing.T) {

internal/controllermanager/prepare_controllers.go

@@ -47,6 +47,9 @@ func PrepareControllers(
 	kubePublicNamespaceK8sInformers, installationNamespaceK8sInformers, installationNamespacePinnipedInformers :=
 		createInformers(serverInstallationNamespace, k8sClient, pinnipedClient)
 
+	// This string must match the name of the Service declared in the deployment yaml.
+	const serviceName = "pinniped-api"
+
 	// Create controller manager.
 	controllerManager := controllerlib.
 		NewManager().
@@ -65,11 +68,21 @@ func PrepareControllers(
 			apicerts.NewCertsManagerController(
 				serverInstallationNamespace,
 				k8sClient,
-				aggregatorClient,
 				installationNamespaceK8sInformers.Core().V1().Secrets(),
 				controllerlib.WithInformer,
 				controllerlib.WithInitialEvent,
 				servingCertDuration,
+				"Pinniped CA",
+				serviceName,
+			),
+			singletonWorker,
+		).
+		WithController(
+			apicerts.NewAPIServiceUpdaterController(
+				serverInstallationNamespace,
+				aggregatorClient,
+				installationNamespaceK8sInformers.Core().V1().Secrets(),
+				controllerlib.WithInformer,
 			),
 			singletonWorker,
 		).