Bump the github-actions group across 1 directory with 2 updates (#892)

Bumps the github-actions group with 2 updates in the / directory: [docker/login-action](https://github.com/docker/login-action) and [docker/build-push-action](https://github.com/docker/build-push-action).


Updates `docker/login-action` from 4.0.0 to 4.1.0
- [Release notes](https://github.com/docker/login-action/releases)
- [Commits](https://github.com/docker/login-action/compare/b45d80f862d83dbcd57f89517bcf500b2ab88fb2...4907a6ddec9925e35a0a9e82d7399ccc52663121)

Updates `docker/build-push-action` from 7.0.0 to 7.1.0
- [Release notes](https://github.com/docker/build-push-action/releases)
- [Commits](https://github.com/docker/build-push-action/compare/d08e5c354a6adb9ed34480a06d141179aa583294...bcafcacb16a39f128d818304e6c9c0c18556b85f)

---
updated-dependencies:
- dependency-name: docker/build-push-action
  dependency-version: 7.1.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: github-actions
- dependency-name: docker/login-action
  dependency-version: 4.1.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: github-actions
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/ci.yaml

@@ -10,13 +10,13 @@ jobs:
   tests:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v5
-    - uses: actions/setup-go@v6.0.0
+    - uses: actions/checkout@v6.0.2
+    - uses: actions/setup-go@v6.4.0
       with:
-        go-version: '^1.25'
+        go-version: '^1.26'
     - run: go version
     - run: go install github.com/mattn/goveralls@latest
-    - run: go install github.com/golangci/golangci-lint/cmd/golangci-lint@latest
+    - run: go install github.com/golangci/golangci-lint/v2/cmd/golangci-lint@latest
     - run: make build.docker
     - run: make test
     - run: make check

.github/workflows/codeql-analysis.yml

@@ -38,16 +38,16 @@ jobs:
 
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v5
+      uses: actions/checkout@v6.0.2
 
     - name: setup go
-      uses: actions/setup-go@v6.0.0
+      uses: actions/setup-go@v6.4.0
       with:
-        go-version: '1.25'
+        go-version: '1.26'
 
     # Initializes the CodeQL tools for scanning.
     - name: Initialize CodeQL
-      uses: github/codeql-action/init@v3
+      uses: github/codeql-action/init@v4
       with:
         languages: ${{ matrix.language }}
         # If you wish to specify custom queries, you can do so here or in a config file.
@@ -61,7 +61,7 @@ jobs:
     # Autobuild attempts to build any compiled languages  (C/C++, C#, or Java).
     # If this step fails, then you should remove it and run the build manually (see below)
     - name: Autobuild
-      uses: github/codeql-action/autobuild@v3
+      uses: github/codeql-action/autobuild@v4
 
     # ℹ️ Command-line programs to run using the OS shell.
     # 📚 See https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#jobsjob_idstepsrun
@@ -74,4 +74,4 @@ jobs:
     #   ./location_of_script_within_repo/buildscript.sh
 
     - name: Perform CodeQL Analysis
-      uses: github/codeql-action/analyze@v3
+      uses: github/codeql-action/analyze@v4

.github/workflows/gh-packages.yaml

@@ -25,15 +25,15 @@ jobs:
       packages: write # to push packages
     steps:
       - name: Checkout
-        uses: actions/checkout@ff7abcd0c3c05ccf6adc123a8cd1fd4fb30fb493
+        uses: actions/checkout@0c366fd6a839edf440554fa01a7085ccba70ac98
 
-      - uses: actions/setup-go@44694675825211faa026b3c33043df3e48a5fa00
+      - uses: actions/setup-go@4a3601121dd01d1626a1e23e37211e3254c1c06c
         with:
           # https://www.npmjs.com/package/semver#caret-ranges-123-025-004
-          go-version: '^1.25'
+          go-version: '^1.26'
 
       - name: Login to Github Container Registry
-        uses: docker/login-action@184bdaa0721073962dff0199f1fb9940f07167d1
+        uses: docker/login-action@4907a6ddec9925e35a0a9e82d7399ccc52663121
         with:
           registry: ${{ env.REGISTRY }}
           username: ${{ github.actor }}
@@ -47,21 +47,21 @@ jobs:
           make build.linux.amd64 build.linux.arm64
 
       - name: Set up QEMU
-        uses: docker/setup-qemu-action@29109295f81e9208d7d86ff1c6c12d2833863392
+        uses: docker/setup-qemu-action@ce360397dd3f832beb865e1373c09c0e9f86d70a
 
       - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@e468171a9de216ec08956ac3ada2f0791b6bd435
+        uses: docker/setup-buildx-action@4d04d5d9486b7bd6fa91e7baf45bbb4f8b9deedd
 
       - name: Login to GitHub Container Registry
         if: github.event_name != 'pull_request'
-        uses: docker/login-action@184bdaa0721073962dff0199f1fb9940f07167d1
+        uses: docker/login-action@4907a6ddec9925e35a0a9e82d7399ccc52663121
         with:
           registry: ghcr.io
           username: ${{ github.actor }}
           password: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Docker meta
-        uses: docker/metadata-action@c1e51972afc2121e065aed6d45c65596fe445f3f
+        uses: docker/metadata-action@030e881283bb7a6894de51c315a6bfe6a94e05cf
         id: meta
         with:
           images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
@@ -70,10 +70,9 @@ jobs:
             type=semver,pattern=v{{major}}.{{minor}}
 
       - name: Build and push
-        uses: docker/build-push-action@263435318d21b8e681c14492fe198d362a7d2c83
+        uses: docker/build-push-action@bcafcacb16a39f128d818304e6c9c0c18556b85f
         with:
           context: .
-          build-args: BASE_IMAGE=gcr.io/distroless/static-debian12
           platforms: linux/amd64,linux/arm64
           push: ${{ github.event_name != 'pull_request' && startsWith(github.ref, 'refs/tags/v') }}
           tags: ${{ steps.meta.outputs.tags }}
@@ -81,10 +80,9 @@ jobs:
 
       # Build and push latest tag
       - name: Build and push latest
-        uses: docker/build-push-action@263435318d21b8e681c14492fe198d362a7d2c83
+        uses: docker/build-push-action@bcafcacb16a39f128d818304e6c9c0c18556b85f
         with:
           context: .
-          build-args: BASE_IMAGE=gcr.io/distroless/static-debian12
           platforms: linux/amd64,linux/arm64
           push: ${{ github.event_name != 'pull_request' }}
           tags: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:latest

.github/workflows/release-chart.yml

@@ -10,7 +10,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6.0.2
         with:
           fetch-depth: 0
 

.golangci.yml

@@ -1,13 +1,29 @@
+version: "2"
 run:
   concurrency: 4
-
 linters:
-  disable-all: true
+  default: none
   enable:
-  - errcheck
-  - gosimple
-  - govet
-  - ineffassign
-  - staticcheck
-  - typecheck
-  - unused
+    - errcheck
+    - govet
+    - ineffassign
+    - staticcheck
+    - unused
+  exclusions:
+    generated: lax
+    presets:
+      - comments
+      - common-false-positives
+      - legacy
+      - std-error-handling
+    paths:
+      - third_party$
+      - builtin$
+      - examples$
+formatters:
+  exclusions:
+    generated: lax
+    paths:
+      - third_party$
+      - builtin$
+      - examples$

Dockerfile

@@ -1,4 +1,4 @@
-ARG BASE_IMAGE=registry.opensource.zalan.do/library/static:latest
+ARG BASE_IMAGE=gcr.io/distroless/static-debian12:latest
 FROM ${BASE_IMAGE}
 LABEL maintainer="Team Teapot @ Zalando SE <team-teapot@zalando.de>"
 

Makefile

@@ -2,7 +2,7 @@
 
 BINARY        ?= kube-metrics-adapter
 VERSION       ?= $(shell git describe --tags --always --dirty)
-IMAGE         ?= registry-write.opensource.zalan.do/teapot/$(BINARY)
+IMAGE         ?= ghcr.io/zalando-incubator/$(BINARY)
 TAG           ?= $(VERSION)
 SOURCES       = $(shell find . -name '*.go')
 DOCKERFILE    ?= Dockerfile
@@ -34,12 +34,12 @@ $(GENERATED): go.mod $(CRD_TYPE_SOURCE) $(OPENAPI)
 	./hack/update-codegen.sh
 
 $(GENERATED_CRDS): $(GENERATED) $(CRD_SOURCES)
-	go run sigs.k8s.io/controller-tools/cmd/controller-gen crd:crdVersions=v1 paths=./pkg/apis/... output:crd:dir=docs
+	go tool controller-gen crd:crdVersions=v1 paths=./pkg/apis/... output:crd:dir=docs
 	mv docs/zalando.org_clusterscalingschedules.yaml docs/cluster_scaling_schedules_crd.yaml
 	mv docs/zalando.org_scalingschedules.yaml docs/scaling_schedules_crd.yaml
 
 $(OPENAPI): go.mod
-	go run k8s.io/kube-openapi/cmd/openapi-gen \
+	go tool openapi-gen \
 		--go-header-file hack/boilerplate.go.txt \
 		--logtostderr \
 		--output-dir pkg/api/generated/openapi \

delivery.yaml

@@ -15,21 +15,6 @@ pipeline:
   - desc: test
     cmd: |
       make test
-  - desc: build
-    cmd: |
-      make build.docker
-  - desc: push
-    cmd: |
-      if [[ $CDP_TARGET_BRANCH == master && ! $CDP_PULL_REQUEST_NUMBER ]]; then
-        IMAGE=registry-write.opensource.zalan.do/teapot/kube-metrics-adapter
-        VERSION=$(git describe --tags --always)
-      else
-        IMAGE=registry-write.opensource.zalan.do/teapot/kube-metrics-adapter-test
-        VERSION=$CDP_BUILD_VERSION
-      fi
-      IMAGE=$IMAGE VERSION=$VERSION make build.docker
-      git diff --stat --exit-code
-      IMAGE=$IMAGE VERSION=$VERSION make build.push
   - desc: Build and push image to Zalando's registry
     cmd: |
       if [[ $CDP_TARGET_BRANCH == master && ! $CDP_PULL_REQUEST_NUMBER ]]; then

docs/helm/templates/custom-metrics-apiservice.yaml

@@ -3,6 +3,13 @@ apiVersion: apiregistration.k8s.io/v1
 kind: APIService
 metadata:
   name: v1beta1.custom.metrics.k8s.io
+  {{- with .Values.customMetricsApi.annotations }}
+  annotations:
+    {{- range $k, $v := . }}
+      {{- $value := $v | quote }}
+      {{- printf "%s: %s" (tpl $k $) (tpl $value $) | nindent 4 }}
+    {{- end }}
+  {{- end }}
 spec:
   service:
     name: kube-metrics-adapter

docs/helm/templates/external-metrics-apiservice.yaml

@@ -3,6 +3,13 @@ apiVersion: apiregistration.k8s.io/v1
 kind: APIService
 metadata:
   name: v1beta1.external.metrics.k8s.io
+  {{- with .Values.externalMetricsApi.annotations }}
+  annotations:
+    {{- range $k, $v := . }}
+      {{- $value := $v | quote }}
+      {{- printf "%s: %s" (tpl $k $) (tpl $value $) | nindent 4 }}
+    {{- end }}
+  {{- end }}
 spec:
   service:
     name: kube-metrics-adapter

docs/helm/values.yaml

@@ -15,7 +15,19 @@ addDirectoryHeader:
 contentionProfiling:
 profiling:
 enableCustomMetricsApi: true
+
+# -- add annotations to the custom metrics apiservice resource, e.g.
+# cert-manager.io/inject-ca-from: {{.Release.Namespace}}/kube-metrics-adapter to inject the CA certificate form a cert-manager-issued cert used for the deployment
+customMetricsApi:
+  annotations: {}
+
 enableExternalMetricsApi: true
+
+# -- add annotations to the custom metrics apiservice resource, e.g.
+# cert-manager.io/inject-ca-from: {{.Release.Namespace}}/kube-metrics-adapter to inject the CA certificate form a cert-manager-issued cert used for the deployment
+externalMetricsApi:
+  annotations: {}
+
 credentialsDirectory:
 disregardIncompatibleHPAs:
 http2MaxStreamsPerConnection:

example/Dockerfile

@@ -1,7 +1,9 @@
-FROM registry.opensource.zalan.do/library/alpine-3:latest
+FROM gcr.io/distroless/static-debian12:latest
 LABEL maintainer="Team Teapot @ Zalando SE <team-teapot@zalando.de>"
 
+ARG TARGETARCH
+
 # add binary
-ADD build/linux/custom-metrics-consumer /
+ADD build/linux/${TARGETARCH}/custom-metrics-consumer /
 
 ENTRYPOINT ["/custom-metrics-consumer"]

example/Makefile

@@ -32,11 +32,14 @@ build/$(BINARY): $(SOURCES)
 build/linux/$(BINARY): $(SOURCES)
 	GOOS=linux GOARCH=amd64 CGO_ENABLED=0 go build $(BUILD_FLAGS) -o build/linux/$(BINARY) -ldflags "$(LDFLAGS)" .
 
+build/linux/amd64/$(BINARY): $(SOURCES)
+	GOOS=linux GOARCH=amd64 CGO_ENABLED=0 go build $(BUILD_FLAGS) -o build/linux/amd64/$(BINARY) -ldflags "$(LDFLAGS)" .
+
+build/linux/arm64/$(BINARY): $(SOURCES)
+	GOOS=linux GOARCH=arm64 CGO_ENABLED=0 go build $(BUILD_FLAGS) -o build/linux/arm64/$(BINARY) -ldflags "$(LDFLAGS)" .
+
 build/osx/$(BINARY): $(SOURCES)
 	GOOS=darwin GOARCH=amd64 CGO_ENABLED=0 go build $(BUILD_FLAGS) -o build/osx/$(BINARY) -ldflags "$(LDFLAGS)" .
 
-build.docker: build.linux
-	docker build --rm -t "$(IMAGE):$(TAG)" -f $(DOCKERFILE) .
-
-build.push: build.docker
-	docker push "$(IMAGE):$(TAG)"
+build.push: build/linux/amd64/$(BINARY) build/linux/arm64/$(BINARY)
+	docker buildx build --rm --build-arg -t "$(IMAGE):$(TAG)" --platform linux/amd64,linux/arm64 --push .

example/main.go

@@ -10,7 +10,7 @@ import (
 
 func metricsHandler(w http.ResponseWriter, r *http.Request) {
 	w.WriteHeader(200)
-	_, err := w.Write([]byte(fmt.Sprintf(`{"queue": {"length": %d}}`, size)))
+	_, err := fmt.Fprintf(w, `{"queue": {"length": %d}}`, size)
 	if err != nil {
 		log.Fatalf("failed to write: %v", err)
 	}

hack/tools.go

@@ -1,23 +0,0 @@
-// +build tools
-
-/*
-Copyright 2019 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.
-*/
-
-// This package imports things required by build scripts, to force `go mod` to see them as dependencies
-package tools
-
-import (
-	_ "k8s.io/code-generator"
-	_ "k8s.io/kube-openapi/cmd/openapi-gen"
-	_ "sigs.k8s.io/controller-tools/cmd/controller-gen"
-)

hack/update-codegen.sh

@@ -31,14 +31,14 @@ APIS_PKG="${GOPKG}/pkg/apis"
 GROUPS_WITH_VERSIONS="${CUSTOM_RESOURCE_NAME}:${CUSTOM_RESOURCE_VERSION}"
 
 echo "Generating deepcopy funcs"
-go run k8s.io/code-generator/cmd/deepcopy-gen \
+go tool deepcopy-gen \
   --output-file zz_generated.deepcopy.go \
   --bounding-dirs "${APIS_PKG}" \
   --go-header-file "${SCRIPT_ROOT}/hack/boilerplate.go.txt" \
   "${APIS_PKG}/${CUSTOM_RESOURCE_NAME}/${CUSTOM_RESOURCE_VERSION}"
 
 echo "Generating clientset for ${GROUPS_WITH_VERSIONS} at ${OUTPUT_PKG}/${CLIENTSET_PKG_NAME:-clientset}"
-go run k8s.io/code-generator/cmd/client-gen \
+go tool client-gen \
   --clientset-name versioned \
   --input-base "" \
   --input "${APIS_PKG}/${CUSTOM_RESOURCE_NAME}/${CUSTOM_RESOURCE_VERSION}" \
@@ -47,14 +47,14 @@ go run k8s.io/code-generator/cmd/client-gen \
   --output-dir "${OUTPUT_DIR}/clientset"
 
 echo "Generating listers for ${GROUPS_WITH_VERSIONS} at ${OUTPUT_PKG}/listers"
-go run k8s.io/code-generator/cmd/lister-gen \
+go tool lister-gen \
   --output-pkg "${OUTPUT_PKG}/listers" \
   --go-header-file "${SCRIPT_ROOT}/hack/boilerplate.go.txt" \
   --output-dir "${OUTPUT_DIR}/listers" \
   "${APIS_PKG}/${CUSTOM_RESOURCE_NAME}/${CUSTOM_RESOURCE_VERSION}"
 
 echo "Generating informers for ${GROUPS_WITH_VERSIONS} at ${OUTPUT_PKG}/informers"
-go run k8s.io/code-generator/cmd/informer-gen \
+go tool informer-gen \
   --versioned-clientset-package "${OUTPUT_PKG}/${CLIENTSET_PKG_NAME:-clientset}/${CLIENTSET_NAME_VERSIONED:-versioned}" \
   --listers-package "${OUTPUT_PKG}/listers" \
   --output-pkg "${OUTPUT_PKG}/informers" \

pkg/apis/zalando.org/v1/types.go

@@ -35,7 +35,7 @@ type ScalingSchedule struct {
 // Identifier returns the namespaced scalingScale Identifier in the format
 // `<namespace>/<name>`.
 func (s *ScalingSchedule) Identifier() string {
-	return s.ObjectMeta.Namespace + "/" + s.ObjectMeta.Name
+	return s.Namespace + "/" + s.Name
 }
 
 // ResourceSpec returns the ScalingScheduleSpec of the ScalingSchedule.
@@ -66,7 +66,7 @@ type ClusterScalingSchedule struct {
 // Identifier returns the cluster scalingScale Identifier in the format
 // `<name>`.
 func (s *ClusterScalingSchedule) Identifier() string {
-	return s.ObjectMeta.Name
+	return s.Name
 }
 
 // ResourceSpec returns the ScalingScheduleSpec of the ClusterScalingSchedule.

pkg/client/clientset/versioned/fake/clientset_generated.go

@@ -34,10 +34,6 @@ import (
 // It's backed by a very simple object tracker that processes creates, updates and deletions as-is,
 // without applying any field management, validations and/or defaults. It shouldn't be considered a replacement
 // for a real clientset and is mostly useful in simple unit tests.
-//
-// DEPRECATED: NewClientset replaces this with support for field management, which significantly improves
-// server side apply testing. NewClientset is only available when apply configurations are generated (e.g.
-// via --with-applyconfig).
 func NewSimpleClientset(objects ...runtime.Object) *Clientset {
 	o := testing.NewObjectTracker(scheme, codecs.UniversalDecoder())
 	for _, obj := range objects {
@@ -51,8 +47,8 @@ func NewSimpleClientset(objects ...runtime.Object) *Clientset {
 	cs.AddReactor("*", "*", testing.ObjectReaction(o))
 	cs.AddWatchReactor("*", func(action testing.Action) (handled bool, ret watch.Interface, err error) {
 		var opts metav1.ListOptions
-		if watchActcion, ok := action.(testing.WatchActionImpl); ok {
-			opts = watchActcion.ListOptions
+		if watchAction, ok := action.(testing.WatchActionImpl); ok {
+			opts = watchAction.ListOptions
 		}
 		gvr := action.GetResource()
 		ns := action.GetNamespace()
@@ -83,6 +79,17 @@ func (c *Clientset) Tracker() testing.ObjectTracker {
 	return c.tracker
 }
 
+// IsWatchListSemanticsSupported informs the reflector that this client
+// doesn't support WatchList semantics.
+//
+// This is a synthetic method whose sole purpose is to satisfy the optional
+// interface check performed by the reflector.
+// Returning true signals that WatchList can NOT be used.
+// No additional logic is implemented here.
+func (c *Clientset) IsWatchListSemanticsUnSupported() bool {
+	return true
+}
+
 var (
 	_ clientset.Interface = &Clientset{}
 	_ testing.FakeClient  = &Clientset{}

pkg/client/informers/externalversions/factory.go

@@ -97,6 +97,7 @@ func NewSharedInformerFactory(client versioned.Interface, defaultResync time.Dur
 // NewFilteredSharedInformerFactory constructs a new instance of sharedInformerFactory.
 // Listers obtained via this SharedInformerFactory will be subject to the same filters
 // as specified here.
+//
 // Deprecated: Please use NewSharedInformerFactoryWithOptions instead
 func NewFilteredSharedInformerFactory(client versioned.Interface, defaultResync time.Duration, namespace string, tweakListOptions internalinterfaces.TweakListOptionsFunc) SharedInformerFactory {
 	return NewSharedInformerFactoryWithOptions(client, defaultResync, WithNamespace(namespace), WithTweakListOptions(tweakListOptions))
@@ -204,7 +205,7 @@ func (f *sharedInformerFactory) InformerFor(obj runtime.Object, newFunc internal
 //
 // It is typically used like this:
 //
-//	ctx, cancel := context.Background()
+//	ctx, cancel := context.WithCancel(context.Background())
 //	defer cancel()
 //	factory := NewSharedInformerFactory(client, resyncPeriod)
 //	defer factory.WaitForStop()    // Returns immediately if nothing was started.

pkg/client/informers/externalversions/zalando.org/v1/clusterscalingschedule.go

@@ -56,7 +56,7 @@ func NewClusterScalingScheduleInformer(client versioned.Interface, resyncPeriod
 // one. This reduces memory footprint and number of connections to the server.
 func NewFilteredClusterScalingScheduleInformer(client versioned.Interface, resyncPeriod time.Duration, indexers cache.Indexers, tweakListOptions internalinterfaces.TweakListOptionsFunc) cache.SharedIndexInformer {
 	return cache.NewSharedIndexInformer(
-		&cache.ListWatch{
+		cache.ToListWatcherWithWatchListSemantics(&cache.ListWatch{
 			ListFunc: func(options metav1.ListOptions) (runtime.Object, error) {
 				if tweakListOptions != nil {
 					tweakListOptions(&options)
@@ -81,7 +81,7 @@ func NewFilteredClusterScalingScheduleInformer(client versioned.Interface, resyn
 				}
 				return client.ZalandoV1().ClusterScalingSchedules().Watch(ctx, options)
 			},
-		},
+		}, client),
 		&apiszalandoorgv1.ClusterScalingSchedule{},
 		resyncPeriod,
 		indexers,

pkg/client/informers/externalversions/zalando.org/v1/scalingschedule.go

@@ -57,7 +57,7 @@ func NewScalingScheduleInformer(client versioned.Interface, namespace string, re
 // one. This reduces memory footprint and number of connections to the server.
 func NewFilteredScalingScheduleInformer(client versioned.Interface, namespace string, resyncPeriod time.Duration, indexers cache.Indexers, tweakListOptions internalinterfaces.TweakListOptionsFunc) cache.SharedIndexInformer {
 	return cache.NewSharedIndexInformer(
-		&cache.ListWatch{
+		cache.ToListWatcherWithWatchListSemantics(&cache.ListWatch{
 			ListFunc: func(options metav1.ListOptions) (runtime.Object, error) {
 				if tweakListOptions != nil {
 					tweakListOptions(&options)
@@ -82,7 +82,7 @@ func NewFilteredScalingScheduleInformer(client versioned.Interface, namespace st
 				}
 				return client.ZalandoV1().ScalingSchedules(namespace).Watch(ctx, options)
 			},
-		},
+		}, client),
 		&apiszalandoorgv1.ScalingSchedule{},
 		resyncPeriod,
 		indexers,

pkg/collector/collector.go

@@ -3,6 +3,7 @@ package collector
 import (
 	"context"
 	"fmt"
+	"strings"
 	"time"
 
 	log "github.com/sirupsen/logrus"
@@ -182,6 +183,25 @@ type MetricTypeName struct {
 	Metric autoscalingv2.MetricIdentifier
 }
 
+func (m MetricTypeName) String() string {
+	str := fmt.Sprintf("%s/%s", m.Type, m.Metric.Name)
+	if m.Metric.Selector != nil && len(m.Metric.Selector.MatchLabels) > 0 {
+		str += " " + mapToString(m.Metric.Selector.MatchLabels)
+	}
+	return str
+}
+
+func mapToString(m map[string]string) string {
+	str := "{"
+	keyVals := make([]string, 0, len(m))
+	for k, v := range m {
+		keyVals = append(keyVals, fmt.Sprintf("%s=%s", k, v))
+	}
+	str += strings.Join(keyVals, ",")
+	str += "}"
+	return str
+}
+
 type CollectedMetric struct {
 	Type      autoscalingv2.MetricSourceType
 	Namespace string

pkg/collector/collector_test.go

@@ -30,6 +30,88 @@ func (c *mockCollector) Interval() time.Duration {
 	return 0
 }
 
+func TestMetricTypeName_String(t *testing.T) {
+	for _, tc := range []struct {
+		name          string
+		metricType    autoscalingv2.MetricSourceType
+		metricName    string
+		selector      *metav1.LabelSelector
+		expectedStr   string
+		shouldContain []string
+	}{
+		{
+			name:        "nil selector with PodsMetricSourceType",
+			metricType:  autoscalingv2.PodsMetricSourceType,
+			metricName:  "metric-name",
+			selector:    nil,
+			expectedStr: "Pods/metric-name",
+		},
+		{
+			name:        "nil selector with ObjectMetricSourceType",
+			metricType:  autoscalingv2.ObjectMetricSourceType,
+			metricName:  "metric-name",
+			selector:    nil,
+			expectedStr: "Object/metric-name",
+		},
+		{
+			name:        "nil selector with ExternalMetricSourceType",
+			metricType:  autoscalingv2.ExternalMetricSourceType,
+			metricName:  "metric-name",
+			selector:    nil,
+			expectedStr: "External/metric-name",
+		},
+		{
+			name:       "empty selector (non-nil but empty MatchLabels)",
+			metricType: autoscalingv2.ExternalMetricSourceType,
+			metricName: "metric-name",
+			selector: &metav1.LabelSelector{
+				MatchLabels: map[string]string{},
+			},
+			expectedStr: "External/metric-name",
+		},
+		{
+			name:       "selector with single MatchLabel",
+			metricType: autoscalingv2.ExternalMetricSourceType,
+			metricName: "metric-name",
+			selector: &metav1.LabelSelector{
+				MatchLabels: map[string]string{"key": "value"},
+			},
+			shouldContain: []string{"External/metric-name", "key=value"},
+		},
+		{
+			name:       "selector with multiple MatchLabels",
+			metricType: autoscalingv2.ExternalMetricSourceType,
+			metricName: "metric-name",
+			selector: &metav1.LabelSelector{
+				MatchLabels: map[string]string{"key1": "val1", "key2": "val2"},
+			},
+			shouldContain: []string{"External/metric-name", "key1=val1", "key2=val2"},
+		},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			mtn := MetricTypeName{
+				Type: tc.metricType,
+				Metric: autoscalingv2.MetricIdentifier{
+					Name:     tc.metricName,
+					Selector: tc.selector,
+				},
+			}
+
+			result := mtn.String()
+
+			if tc.expectedStr != "" {
+				require.Equal(t, tc.expectedStr, result)
+			}
+
+			if len(tc.shouldContain) > 0 {
+				for _, substring := range tc.shouldContain {
+					require.Contains(t, result, substring, "result should contain %q", substring)
+				}
+			}
+		})
+	}
+}
+
 func TestNewCollector(t *testing.T) {
 	for _, tc := range []struct {
 		msg               string

pkg/collector/external_rps_collector.go

@@ -63,7 +63,7 @@ func (p *ExternalRPSCollectorPlugin) NewCollector(
 	confCopy := *config
 
 	if _, ok := config.Config["hostnames"]; !ok {
-		return nil, fmt.Errorf("Hostname is not specified, unable to create collector")
+		return nil, fmt.Errorf("hostname is not specified, unable to create collector")
 	}
 
 	hostnames := strings.Split(config.Config["hostnames"], ",")

pkg/collector/fake_collector_test.go

@@ -1,9 +1,9 @@
 package collector
 
 import (
+	"context"
 	"time"
 
-	"golang.org/x/net/context"
 	autoscalingv2 "k8s.io/api/autoscaling/v2"
 	"k8s.io/apimachinery/pkg/api/resource"
 	"k8s.io/metrics/pkg/apis/custom_metrics"

pkg/collector/http_collector_test.go

@@ -10,7 +10,6 @@ import (
 	"github.com/stretchr/testify/require"
 	autoscalingv2 "k8s.io/api/autoscaling/v2"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
-	v1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 )
 
 type testExternalMetricsHandler struct {
@@ -84,7 +83,7 @@ func makeTestHTTPCollectorConfig(endpoint, aggregator string) *MetricConfig {
 			Type: autoscalingv2.ExternalMetricSourceType,
 			Metric: autoscalingv2.MetricIdentifier{
 				Name: "test-metric",
-				Selector: &v1.LabelSelector{
+				Selector: &metav1.LabelSelector{
 					MatchLabels: map[string]string{"type": HTTPJSONPathType},
 				},
 			},

pkg/collector/httpmetrics/pod_metrics.go

@@ -2,6 +2,7 @@ package httpmetrics
 
 import (
 	"fmt"
+	"net"
 	"net/url"
 	"strconv"
 	"time"
@@ -88,7 +89,7 @@ func NewPodMetricsJSONPathGetter(config map[string]string) (*PodMetricsJSONPathG
 			return nil, err
 		}
 		if d < 0 {
-			return nil, fmt.Errorf("Invalid request-timeout config value: %s", v)
+			return nil, fmt.Errorf("invalid request-timeout config value: %s", v)
 		}
 		requestTimeout = d
 	}
@@ -99,7 +100,7 @@ func NewPodMetricsJSONPathGetter(config map[string]string) (*PodMetricsJSONPathG
 			return nil, err
 		}
 		if d < 0 {
-			return nil, fmt.Errorf("Invalid connect-timeout config value: %s", v)
+			return nil, fmt.Errorf("invalid connect-timeout config value: %s", v)
 		}
 		connectTimeout = d
 	}
@@ -122,7 +123,7 @@ func (g *PodMetricsJSONPathGetter) buildMetricsURL(podIP string) url.URL {
 
 	return url.URL{
 		Scheme:   scheme,
-		Host:     fmt.Sprintf("%s:%d", podIP, g.port),
+		Host:     net.JoinHostPort(podIP, strconv.Itoa(g.port)),
 		Path:     g.path,
 		RawQuery: g.rawQuery,
 	}