Serve OpenAPI spec

Signed-off-by: Mikkel Oscar Lyderik Larsen <mikkel.larsen@zalando.de>

Makefile

@@ -1,19 +1,22 @@
 .PHONY: clean test check build.local build.linux build.osx build.docker build.push
 
-BINARY        ?= kube-metrics-adapter
-VERSION       ?= $(shell git describe --tags --always --dirty)
-IMAGE         ?= registry-write.opensource.zalan.do/teapot/$(BINARY)
-TAG           ?= $(VERSION)
-SOURCES       = $(shell find . -name '*.go')
-DOCKERFILE    ?= Dockerfile
-GOPKGS        = $(shell go list ./...)
-BUILD_FLAGS   ?= -v
-LDFLAGS       ?= -X main.version=$(VERSION) -w -s
+BINARY          ?= kube-metrics-adapter
+VERSION         ?= $(shell git describe --tags --always --dirty)
+IMAGE           ?= registry-write.opensource.zalan.do/teapot/$(BINARY)
+TAG             ?= $(VERSION)
+SOURCES         = $(shell find . -name '*.go')
+DOCKERFILE      ?= Dockerfile
+GOPKGS          = $(shell go list ./...)
+GO_OPENAPI_GEN = ./build/openapi-gen
+OPENAPI_GEN     = pkg/apiserver/generated/openapi/zz_generated.openapi.go
+BUILD_FLAGS     ?= -v
+LDFLAGS         ?= -X main.version=$(VERSION) -w -s
 
 default: build.local
 
 clean:
 	rm -rf build
+	rm -rf $(OPENAPI_GEN)
 
 test:
 	go test -v $(GOPKGS)
@@ -22,17 +25,24 @@ check:
 	go mod download
 	golangci-lint run --timeout=2m ./...
 
+$(GO_OPENAPI_GEN):
+	mkdir -p build
+	GOBIN=$(shell pwd)/build go install k8s.io/kube-openapi/cmd/openapi-gen
+
+$(OPENAPI_GEN): $(GO_OPENAPI_GEN)
+	$(GO_OPENAPI_GEN) -o . --go-header-file hack/boilerplate.go.txt --logtostderr -i k8s.io/metrics/pkg/apis/custom_metrics,k8s.io/metrics/pkg/apis/custom_metrics/v1beta1,k8s.io/metrics/pkg/apis/custom_metrics/v1beta2,k8s.io/metrics/pkg/apis/external_metrics,k8s.io/metrics/pkg/apis/external_metrics/v1beta1,k8s.io/apimachinery/pkg/apis/meta/v1,k8s.io/apimachinery/pkg/api/resource,k8s.io/apimachinery/pkg/version,k8s.io/api/core/v1 -p pkg/apiserver/generated/openapi -O zz_generated.openapi -r /dev/null
+
 build.local: build/$(BINARY)
 build.linux: build/linux/$(BINARY)
 build.osx: build/osx/$(BINARY)
 
-build/$(BINARY): go.mod $(SOURCES)
+build/$(BINARY): go.mod $(OPENAPI_GEN) $(SOURCES)
 	CGO_ENABLED=0 go build -o build/$(BINARY) $(BUILD_FLAGS) -ldflags "$(LDFLAGS)" .
 
-build/linux/$(BINARY): go.mod $(SOURCES)
+build/linux/$(BINARY): go.mod $(OPENAPI_GEN) $(SOURCES)
 	GOOS=linux GOARCH=amd64 CGO_ENABLED=0 go build $(BUILD_FLAGS) -o build/linux/$(BINARY) -ldflags "$(LDFLAGS)" .
 
-build/osx/$(BINARY): go.mod $(SOURCES)
+build/osx/$(BINARY): go.mod $(OPENAPI_GEN) $(SOURCES)
 	GOOS=darwin GOARCH=amd64 CGO_ENABLED=0 go build $(BUILD_FLAGS) -o build/osx/$(BINARY) -ldflags "$(LDFLAGS)" .
 
 build.docker: build.linux

go.mod

@@ -3,13 +3,13 @@ module github.com/zalando-incubator/kube-metrics-adapter
 require (
 	github.com/NYTimes/gziphandler v1.0.1 // indirect
 	github.com/aws/aws-sdk-go v1.31.7
+	github.com/go-openapi/spec v0.19.3
 	github.com/googleapis/gnostic v0.2.0 // indirect
 	github.com/influxdata/influxdb-client-go v0.1.5
-	github.com/kubernetes-incubator/custom-metrics-apiserver v0.0.0-20200323093244-5046ce1afe6b
+	github.com/kubernetes-incubator/custom-metrics-apiserver v0.0.0-20200618121405-54026617ec44
 	github.com/lib/pq v1.2.0 // indirect
 	github.com/mattn/go-colorable v0.1.4 // indirect
 	github.com/oliveagle/jsonpath v0.0.0-20180606110733-2e52cf6e6852
-	github.com/onsi/ginkgo v1.11.0 // indirect
 	github.com/onsi/gomega v1.8.1 // indirect
 	github.com/prometheus/client_golang v1.6.0
 	github.com/prometheus/common v0.10.0
@@ -17,16 +17,19 @@ require (
 	github.com/spf13/cobra v0.0.7
 	github.com/stretchr/testify v1.6.0
 	github.com/zalando-incubator/cluster-lifecycle-manager v0.0.0-20180921141935-824b77fb1f84
-	golang.org/x/crypto v0.0.0-20200220183623-bac4c82f6975 // indirect
 	golang.org/x/oauth2 v0.0.0-20190604053449-0f29369cfe45
 	golang.org/x/tools v0.0.0-20200204192400-7124308813f3 // indirect
+	gonum.org/v1/netlib v0.0.0-20190331212654-76723241ea4e // indirect
 	honnef.co/go/tools v0.0.1-2020.1.3 // indirect
-	k8s.io/api v0.17.3
-	k8s.io/apimachinery v0.17.4
-	k8s.io/client-go v0.17.3
-	k8s.io/component-base v0.17.3
+	k8s.io/api v0.18.4
+	k8s.io/apiextensions-apiserver v0.18.4
+	k8s.io/apimachinery v0.18.4
+	k8s.io/apiserver v0.18.4
+	k8s.io/client-go v0.18.4
+	k8s.io/component-base v0.18.4
 	k8s.io/klog v1.0.0
-	k8s.io/metrics v0.17.3
+	k8s.io/kube-openapi v0.0.0-20200410145947-61e04a5be9a6
+	k8s.io/metrics v0.18.4
 )
 
 go 1.13

hack/boilerplate.go.txt

@@ -0,0 +1,15 @@
+/*
+Copyright YEAR 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.
+*/

pkg/collector/pod_collector.go

@@ -1,6 +1,7 @@
 package collector
 
 import (
+	"context"
 	"fmt"
 	"net/http"
 	"time"
@@ -8,9 +9,9 @@ import (
 	log "github.com/sirupsen/logrus"
 	"github.com/zalando-incubator/kube-metrics-adapter/pkg/collector/httpmetrics"
 	autoscalingv2 "k8s.io/api/autoscaling/v2beta2"
+	corev1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/api/resource"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
-	corev1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/labels"
 	"k8s.io/client-go/kubernetes"
 	"k8s.io/metrics/pkg/apis/custom_metrics"
@@ -81,7 +82,7 @@ func (c *PodCollector) GetMetrics() ([]CollectedMetric, error) {
 		LabelSelector: labels.Set(c.podLabelSelector.MatchLabels).String(),
 	}
 
-	pods, err := c.client.CoreV1().Pods(c.namespace).List(opts)
+	pods, err := c.client.CoreV1().Pods(c.namespace).List(context.TODO(), opts)
 	if err != nil {
 		return nil, err
 	}
@@ -95,9 +96,9 @@ func (c *PodCollector) GetMetrics() ([]CollectedMetric, error) {
 	values := make([]CollectedMetric, 0, len(pods.Items))
 	for i := 0; i < len(pods.Items); i++ {
 		select {
-		case err := <- errCh:
+		case err := <-errCh:
 			c.logger.Error(err)
-		case resp := <- ch:
+		case resp := <-ch:
 			values = append(values, resp)
 		}
 	}
@@ -135,13 +136,13 @@ func (c *PodCollector) getPodMetric(pod corev1.Pod, ch chan CollectedMetric, err
 func getPodLabelSelector(client kubernetes.Interface, hpa *autoscalingv2.HorizontalPodAutoscaler) (*metav1.LabelSelector, error) {
 	switch hpa.Spec.ScaleTargetRef.Kind {
 	case "Deployment":
-		deployment, err := client.AppsV1().Deployments(hpa.Namespace).Get(hpa.Spec.ScaleTargetRef.Name, metav1.GetOptions{})
+		deployment, err := client.AppsV1().Deployments(hpa.Namespace).Get(context.TODO(), hpa.Spec.ScaleTargetRef.Name, metav1.GetOptions{})
 		if err != nil {
 			return nil, err
 		}
 		return deployment.Spec.Selector, nil
 	case "StatefulSet":
-		sts, err := client.AppsV1().StatefulSets(hpa.Namespace).Get(hpa.Spec.ScaleTargetRef.Name, metav1.GetOptions{})
+		sts, err := client.AppsV1().StatefulSets(hpa.Namespace).Get(context.TODO(), hpa.Spec.ScaleTargetRef.Name, metav1.GetOptions{})
 		if err != nil {
 			return nil, err
 		}

pkg/collector/pod_collector_test.go

@@ -1,14 +1,15 @@
 package collector
 
 import (
+	"context"
 	"encoding/json"
 	"fmt"
 	"net/http"
 	"net/http/httptest"
 	"net/url"
+	"sync"
 	"testing"
 	"time"
-	"sync"
 
 	"github.com/stretchr/testify/require"
 	appsv1 "k8s.io/api/apps/v1"
@@ -115,7 +116,7 @@ func makeTestPods(t *testing.T, testServer string, metricName string, port strin
 				PodIP: testServer,
 			},
 		}
-		_, err := client.CoreV1().Pods(testNamespace).Create(testPod)
+		_, err := client.CoreV1().Pods(testNamespace).Create(context.TODO(), testPod, v1.CreateOptions{})
 		require.NoError(t, err)
 	}
 }
@@ -129,7 +130,7 @@ func makeTestDeployment(t *testing.T, client kubernetes.Interface) *appsv1.Deplo
 			},
 		},
 	}
-	_, err := client.AppsV1().Deployments(testNamespace).Create(&deployment)
+	_, err := client.AppsV1().Deployments(testNamespace).Create(context.TODO(), &deployment, v1.CreateOptions{})
 	require.NoError(t, err)
 	return &deployment
 
@@ -149,7 +150,7 @@ func makeTestHPA(t *testing.T, client kubernetes.Interface) *autoscalingv2.Horiz
 			},
 		},
 	}
-	_, err := client.AutoscalingV2beta2().HorizontalPodAutoscalers("test-namespace").Create(hpa)
+	_, err := client.AutoscalingV2beta2().HorizontalPodAutoscalers("test-namespace").Create(context.TODO(), hpa, v1.CreateOptions{})
 	require.NoError(t, err)
 	return hpa
 }

pkg/collector/skipper_collector.go

@@ -1,6 +1,7 @@
 package collector
 
 import (
+	"context"
 	"encoding/json"
 	"errors"
 	"fmt"
@@ -125,7 +126,7 @@ func getWeights(ingressAnnotations map[string]string, backendAnnotations []strin
 
 // getCollector returns a collector for getting the metrics.
 func (c *SkipperCollector) getCollector() (Collector, error) {
-	ingress, err := c.client.NetworkingV1beta1().Ingresses(c.objectReference.Namespace).Get(c.objectReference.Name, metav1.GetOptions{})
+	ingress, err := c.client.NetworkingV1beta1().Ingresses(c.objectReference.Namespace).Get(context.TODO(), c.objectReference.Name, metav1.GetOptions{})
 	if err != nil {
 		return nil, err
 	}
@@ -207,13 +208,13 @@ func targetRefReplicas(client kubernetes.Interface, hpa *autoscalingv2.Horizonta
 	var replicas int32
 	switch hpa.Spec.ScaleTargetRef.Kind {
 	case "Deployment":
-		deployment, err := client.AppsV1().Deployments(hpa.Namespace).Get(hpa.Spec.ScaleTargetRef.Name, metav1.GetOptions{})
+		deployment, err := client.AppsV1().Deployments(hpa.Namespace).Get(context.TODO(), hpa.Spec.ScaleTargetRef.Name, metav1.GetOptions{})
 		if err != nil {
 			return 0, err
 		}
 		replicas = deployment.Status.Replicas
 	case "StatefulSet":
-		sts, err := client.AppsV1().StatefulSets(hpa.Namespace).Get(hpa.Spec.ScaleTargetRef.Name, metav1.GetOptions{})
+		sts, err := client.AppsV1().StatefulSets(hpa.Namespace).Get(context.TODO(), hpa.Spec.ScaleTargetRef.Name, metav1.GetOptions{})
 		if err != nil {
 			return 0, err
 		}

pkg/collector/skipper_collector_test.go

@@ -1,6 +1,7 @@
 package collector
 
 import (
+	"context"
 	"encoding/json"
 	"fmt"
 	"testing"
@@ -32,7 +33,7 @@ func TestTargetRefReplicasDeployments(t *testing.T) {
 
 	// Create an HPA with the deployment as ref
 	hpa, err := client.AutoscalingV2beta2().HorizontalPodAutoscalers(deployment.Namespace).
-		Create(newHPA(defaultNamespace, name, "Deployment"))
+		Create(context.TODO(), newHPA(defaultNamespace, name, "Deployment"), metav1.CreateOptions{})
 	require.NoError(t, err)
 
 	replicas, err := targetRefReplicas(client, hpa)
@@ -49,7 +50,7 @@ func TestTargetRefReplicasStatefulSets(t *testing.T) {
 
 	// Create an HPA with the statefulSet as ref
 	hpa, err := client.AutoscalingV2beta2().HorizontalPodAutoscalers(statefulSet.Namespace).
-		Create(newHPA(defaultNamespace, name, "StatefulSet"))
+		Create(context.TODO(), newHPA(defaultNamespace, name, "StatefulSet"), metav1.CreateOptions{})
 	require.NoError(t, err)
 
 	replicas, err := targetRefReplicas(client, hpa)
@@ -73,7 +74,7 @@ func newHPA(namesapce string, refName string, refKind string) *autoscalingv2.Hor
 }
 
 func newDeployment(client *fake.Clientset, namespace string, name string, replicas, readyReplicas int32) (*appsv1.Deployment, error) {
-	return client.AppsV1().Deployments(namespace).Create(&appsv1.Deployment{
+	return client.AppsV1().Deployments(namespace).Create(context.TODO(), &appsv1.Deployment{
 		ObjectMeta: metav1.ObjectMeta{
 			Name:      name,
 			Namespace: namespace,
@@ -83,11 +84,11 @@ func newDeployment(client *fake.Clientset, namespace string, name string, replic
 			ReadyReplicas: replicas,
 			Replicas:      readyReplicas,
 		},
-	})
+	}, metav1.CreateOptions{})
 }
 
 func newStatefulSet(client *fake.Clientset, namespace string, name string) (*appsv1.StatefulSet, error) {
-	return client.AppsV1().StatefulSets(namespace).Create(&appsv1.StatefulSet{
+	return client.AppsV1().StatefulSets(namespace).Create(context.TODO(), &appsv1.StatefulSet{
 		ObjectMeta: metav1.ObjectMeta{
 			Name:      name,
 			Namespace: namespace,
@@ -96,7 +97,7 @@ func newStatefulSet(client *fake.Clientset, namespace string, name string) (*app
 			ReadyReplicas: 1,
 			Replicas:      2,
 		},
-	})
+	}, metav1.CreateOptions{})
 }
 
 func TestSkipperCollector(t *testing.T) {
@@ -382,7 +383,7 @@ func makeIngress(client kubernetes.Interface, namespace, ingressName, backend st
 			Host: hostname,
 		})
 	}
-	_, err := client.NetworkingV1beta1().Ingresses(namespace).Create(ingress)
+	_, err := client.NetworkingV1beta1().Ingresses(namespace).Create(context.TODO(), ingress, metav1.CreateOptions{})
 	return err
 }
 

pkg/provider/hpa.go

@@ -119,7 +119,7 @@ func (p *HPAProvider) Run(ctx context.Context) {
 func (p *HPAProvider) updateHPAs() error {
 	p.logger.Info("Looking for HPAs")
 
-	hpas, err := p.client.AutoscalingV2beta2().HorizontalPodAutoscalers(metav1.NamespaceAll).List(metav1.ListOptions{})
+	hpas, err := p.client.AutoscalingV2beta2().HorizontalPodAutoscalers(metav1.NamespaceAll).List(context.TODO(), metav1.ListOptions{})
 	if err != nil {
 		return err
 	}

pkg/provider/hpa_test.go

@@ -70,7 +70,7 @@ func TestUpdateHPAs(t *testing.T) {
 	fakeClient := fake.NewSimpleClientset()
 
 	var err error
-	hpa, err = fakeClient.AutoscalingV2beta2().HorizontalPodAutoscalers("default").Create(hpa)
+	hpa, err = fakeClient.AutoscalingV2beta2().HorizontalPodAutoscalers("default").Create(context.TODO(), hpa, metav1.CreateOptions{})
 	require.NoError(t, err)
 
 	collectorFactory := collector.NewCollectorFactory()
@@ -86,7 +86,7 @@ func TestUpdateHPAs(t *testing.T) {
 
 	// update HPA
 	hpa.Annotations["metric-config.pods.requests-per-second.json-path/port"] = "8080"
-	_, err = fakeClient.AutoscalingV2beta2().HorizontalPodAutoscalers("default").Update(hpa)
+	_, err = fakeClient.AutoscalingV2beta2().HorizontalPodAutoscalers("default").Update(context.TODO(), hpa, metav1.UpdateOptions{})
 	require.NoError(t, err)
 
 	err = provider.updateHPAs()
@@ -134,7 +134,7 @@ func TestUpdateHPAsDisregardingIncompatibleHPA(t *testing.T) {
 	fakeClient := fake.NewSimpleClientset()
 
 	var err error
-	_, err = fakeClient.AutoscalingV2beta2().HorizontalPodAutoscalers("default").Create(hpa)
+	_, err = fakeClient.AutoscalingV2beta2().HorizontalPodAutoscalers("default").Create(context.TODO(), hpa, metav1.CreateOptions{})
 	require.NoError(t, err)
 
 	collectorFactory := collector.NewCollectorFactory()

pkg/server/start.go

@@ -29,10 +29,14 @@ import (
 	"github.com/prometheus/client_golang/prometheus/promhttp"
 	"github.com/spf13/cobra"
 	"github.com/zalando-incubator/cluster-lifecycle-manager/pkg/credentials-loader/platformiam"
+	generatedopenapi "github.com/zalando-incubator/kube-metrics-adapter/pkg/apiserver/generated/openapi"
 	"github.com/zalando-incubator/kube-metrics-adapter/pkg/collector"
 	"github.com/zalando-incubator/kube-metrics-adapter/pkg/provider"
 	"github.com/zalando-incubator/kube-metrics-adapter/pkg/zmon"
 	"golang.org/x/oauth2"
+	"k8s.io/apiextensions-apiserver/pkg/apiserver"
+	openapinamer "k8s.io/apiserver/pkg/endpoints/openapi"
+	genericapiserver "k8s.io/apiserver/pkg/server"
 	"k8s.io/client-go/informers"
 	"k8s.io/client-go/kubernetes"
 	"k8s.io/client-go/rest"
@@ -126,6 +130,10 @@ func (o AdapterServerOptions) RunCustomMetricsAdapterServer(stopCh <-chan struct
 		return err
 	}
 
+	config.GenericConfig.OpenAPIConfig = genericapiserver.DefaultOpenAPIConfig(generatedopenapi.GetOpenAPIDefinitions, openapinamer.NewDefinitionNamer(apiserver.Scheme))
+	config.GenericConfig.OpenAPIConfig.Info.Title = "kube-metrics-adapter"
+	config.GenericConfig.OpenAPIConfig.Info.Version = "1.0.0"
+
 	var clientConfig *rest.Config
 	if len(o.RemoteKubeConfigFile) > 0 {
 		loadingRules := &clientcmd.ClientConfigLoadingRules{ExplicitPath: o.RemoteKubeConfigFile}

tools.go

@@ -0,0 +1,7 @@
+// +build tools
+
+package main
+
+import (
+	_ "k8s.io/kube-openapi/cmd/openapi-gen"
+)