Serve OpenAPI spec

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

.travis.yml

@@ -2,7 +2,7 @@ language: go
 dist: xenial
 
 go:
-  - "1.13.x"
+  - "1.14.x"
 
 env:
 - GO111MODULE=on GOLANGCI_RELEASE="v1.21.0"

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

README.md

@@ -166,6 +166,14 @@ will create a URL like this:
 http://<podIP>:9090/metrics?foo=bar&baz=bop
 ```
 
+There are also configuration options for custom (connect and request) timeouts when querying pods for metrics:
+```yaml
+metric-config.pods.requests-per-second.json-path/request-timeout: 2s
+metric-config.pods.requests-per-second.json-path/connect-timeout: 500ms
+```
+
+The default for both of the above values is 15 seconds.
+
 ## Prometheus collector
 
 The Prometheus collector is a generic collector which can map Prometheus

go.mod

@@ -2,31 +2,34 @@ module github.com/zalando-incubator/kube-metrics-adapter
 
 require (
 	github.com/NYTimes/gziphandler v1.0.1 // indirect
-	github.com/aws/aws-sdk-go v1.30.2
+	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 v1.5.1
-	github.com/prometheus/common v0.9.1
-	github.com/sirupsen/logrus v1.5.0
+	github.com/prometheus/client_golang v1.6.0
+	github.com/prometheus/common v0.10.0
+	github.com/sirupsen/logrus v1.6.0
 	github.com/spf13/cobra v0.0.7
-	github.com/stretchr/testify v1.5.1
+	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/httpmetrics/json_path.go

@@ -26,21 +26,28 @@ func NewJSONPathMetricsGetter(httpClient *http.Client, aggregatorFunc Aggregator
 	return &JSONPathMetricsGetter{client: httpClient, aggregator: aggregatorFunc, jsonPath: compiledPath}
 }
 
-func DefaultMetricsHTTPClient() *http.Client {
+var DefaultRequestTimeout = 15 * time.Second
+var DefaultConnectTimeout = 15 * time.Second
+
+func CustomMetricsHTTPClient(requestTimeout time.Duration, connectTimeout time.Duration) *http.Client {
 	client := &http.Client{
 		Transport: &http.Transport{
 			DialContext: (&net.Dialer{
-				Timeout: 15 * time.Second,
+				Timeout: connectTimeout,
 			}).DialContext,
 			MaxIdleConns:          50,
 			IdleConnTimeout:       90 * time.Second,
 			ExpectContinueTimeout: 1 * time.Second,
 		},
-		Timeout: 15 * time.Second,
+		Timeout: requestTimeout,
 	}
 	return client
 }
 
+func DefaultMetricsHTTPClient() *http.Client {
+	return CustomMetricsHTTPClient(DefaultRequestTimeout, DefaultConnectTimeout)
+}
+
 // GetMetric gets metric from pod by fetching json metrics from the pods metric
 // endpoint and extracting the desired value using the specified json path
 // query.

pkg/collector/httpmetrics/pod_metrics.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"net/url"
 	"strconv"
+	"time"
 
 	"github.com/oliveagle/jsonpath"
 	v1 "k8s.io/api/core/v1"
@@ -72,7 +73,33 @@ func NewPodMetricsJSONPathGetter(config map[string]string) (*PodMetricsJSONPathG
 			return nil, err
 		}
 	}
-	getter.metricGetter = NewJSONPathMetricsGetter(DefaultMetricsHTTPClient(), aggregator, jsonPath)
+
+	requestTimeout := DefaultRequestTimeout
+	connectTimeout := DefaultConnectTimeout
+
+	if v, ok := config["request-timeout"]; ok {
+		d, err := time.ParseDuration(v)
+		if err != nil {
+			return nil, err
+		}
+		if d < 0 {
+			return nil, fmt.Errorf("Invalid request-timeout config value: %s", v)
+		}
+		requestTimeout = d
+	}
+
+	if v, ok := config["connect-timeout"]; ok {
+		d, err := time.ParseDuration(v)
+		if err != nil {
+			return nil, err
+		}
+		if d < 0 {
+			return nil, fmt.Errorf("Invalid connect-timeout config value: %s", v)
+		}
+		connectTimeout = d
+	}
+
+	getter.metricGetter = NewJSONPathMetricsGetter(CustomMetricsHTTPClient(requestTimeout, connectTimeout), aggregator, jsonPath)
 	return &getter, nil
 }
 

pkg/collector/httpmetrics/pod_metrics_test.go

@@ -3,6 +3,7 @@ package httpmetrics
 import (
 	"fmt"
 	"testing"
+	"time"
 
 	"github.com/oliveagle/jsonpath"
 	"github.com/stretchr/testify/require"
@@ -131,3 +132,67 @@ func TestBuildMetricsURL(t *testing.T) {
 	receivedURLNoQuery := getterWithNoQuery.buildMetricsURL(ip)
 	require.Equal(t, receivedURLNoQuery.String(), expectedURLNoQuery)
 }
+
+func TestCustomTimeouts(t *testing.T) {
+	scheme := "http"
+	port := "9090"
+	path := "/v1/test/"
+
+	// Test no custom options results in default timeouts
+	defaultConfig := map[string]string{
+		"json-key":  "$.value",
+		"scheme":    scheme,
+		"path":      path,
+		"port":      port,
+	}
+	defaultTime := time.Duration(15000) * time.Millisecond
+
+	defaultGetter, err1 := NewPodMetricsJSONPathGetter(defaultConfig)
+	require.NoError(t, err1)
+	require.Equal(t, defaultGetter.metricGetter.client.Timeout, defaultTime)
+
+	// Test with custom request timeout
+	configWithRequestTimeout := map[string]string{
+		"json-key":  "$.value",
+		"scheme":    scheme,
+		"path":      path,
+		"port":      port,
+		"request-timeout": "978ms",
+	}
+	exectedTimeout := time.Duration(978) * time.Millisecond
+	customRequestGetter, err2 := NewPodMetricsJSONPathGetter(configWithRequestTimeout)
+	require.NoError(t, err2)
+	require.Equal(t, customRequestGetter.metricGetter.client.Timeout, exectedTimeout)
+
+	// Test with custom connect timeout. Unfortunately, it seems there's no way to access the
+	// connect timeout of the client struct to actually verify it's set :/
+	configWithConnectTimeout := map[string]string{
+		"json-key":  "$.value",
+		"scheme":    scheme,
+		"path":      path,
+		"port":      port,
+		"connect-timeout": "512ms",
+	}
+	customRequestGetter, err3 := NewPodMetricsJSONPathGetter(configWithConnectTimeout)
+	require.NoError(t, err3)
+
+	configWithInvalidTimeout := map[string]string{
+		"json-key":  "$.value",
+		"scheme":    scheme,
+		"path":      path,
+		"port":      port,
+		"request-timeout": "-256ms",
+	}
+	_, err4 := NewPodMetricsJSONPathGetter(configWithInvalidTimeout)
+	require.Error(t, err4)
+
+	configWithInvalidTimeout = map[string]string{
+		"json-key":  "$.value",
+		"scheme":    scheme,
+		"path":      path,
+		"port":      port,
+		"connect-timeout": "-256ms",
+	}
+	_, err5 := NewPodMetricsJSONPathGetter(configWithInvalidTimeout)
+	require.Error(t, err5)
+}

pkg/collector/pod_collector.go

@@ -1,6 +1,7 @@
 package collector
 
 import (
+	"context"
 	"fmt"
 	"net/http"
 	"time"
@@ -8,6 +9,7 @@ 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"
 	"k8s.io/apimachinery/pkg/labels"
@@ -80,37 +82,25 @@ 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
 	}
 
-	values := make([]CollectedMetric, 0, len(pods.Items))
-
-	// TODO: get metrics in parallel
+	ch := make(chan CollectedMetric)
+	errCh := make(chan error)
 	for _, pod := range pods.Items {
-		value, err := c.Getter.GetMetric(&pod)
-		if err != nil {
-			c.logger.Errorf("Failed to get metrics from pod '%s/%s': %v", pod.Namespace, pod.Name, err)
-			continue
-		}
+		go c.getPodMetric(pod, ch, errCh)
+	}
 
-		metricValue := CollectedMetric{
-			Type: c.metricType,
-			Custom: custom_metrics.MetricValue{
-				DescribedObject: custom_metrics.ObjectReference{
-					APIVersion: "v1",
-					Kind:       "Pod",
-					Name:       pod.Name,
-					Namespace:  pod.Namespace,
-				},
-				Metric:    custom_metrics.MetricIdentifier{Name: c.metric.Name, Selector: c.podLabelSelector},
-				Timestamp: metav1.Time{Time: time.Now().UTC()},
-				Value:     *resource.NewMilliQuantity(int64(value*1000), resource.DecimalSI),
-			},
+	values := make([]CollectedMetric, 0, len(pods.Items))
+	for i := 0; i < len(pods.Items); i++ {
+		select {
+		case err := <-errCh:
+			c.logger.Error(err)
+		case resp := <-ch:
+			values = append(values, resp)
 		}
-
-		values = append(values, metricValue)
 	}
 
 	return values, nil
@@ -120,16 +110,39 @@ func (c *PodCollector) Interval() time.Duration {
 	return c.interval
 }
 
+func (c *PodCollector) getPodMetric(pod corev1.Pod, ch chan CollectedMetric, errCh chan error) {
+	value, err := c.Getter.GetMetric(&pod)
+	if err != nil {
+		errCh <- fmt.Errorf("Failed to get metrics from pod '%s/%s': %v", pod.Namespace, pod.Name, err)
+		return
+	}
+
+	ch <- CollectedMetric{
+		Type: c.metricType,
+		Custom: custom_metrics.MetricValue{
+			DescribedObject: custom_metrics.ObjectReference{
+				APIVersion: "v1",
+				Kind:       "Pod",
+				Name:       pod.Name,
+				Namespace:  pod.Namespace,
+			},
+			Metric:    custom_metrics.MetricIdentifier{Name: c.metric.Name, Selector: c.podLabelSelector},
+			Timestamp: metav1.Time{Time: time.Now().UTC()},
+			Value:     *resource.NewMilliQuantity(int64(value*1000), resource.DecimalSI),
+		},
+	}
+}
+
 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

@@ -1,11 +1,13 @@
 package collector
 
 import (
+	"context"
 	"encoding/json"
 	"fmt"
 	"net/http"
 	"net/http/httptest"
 	"net/url"
+	"sync"
 	"testing"
 	"time"
 
@@ -55,7 +57,7 @@ func TestPodCollector(t *testing.T) {
 			for _, m := range metrics {
 				values = append(values, m.Custom.Value.Value())
 			}
-			require.Equal(t, tc.result, values)
+			require.ElementsMatch(t, tc.result, values)
 		})
 	}
 }
@@ -68,9 +70,13 @@ type testMetricsHandler struct {
 	calledCounter uint
 	t             *testing.T
 	metricsPath   string
+	sync.RWMutex
 }
 
 func (h *testMetricsHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	h.Lock()
+	defer h.Unlock()
+
 	require.Equal(h.t, h.metricsPath, r.URL.Path)
 	require.Less(h.t, int(h.calledCounter), len(h.values))
 	response, err := json.Marshal(testMetricResponse{Values: h.values[h.calledCounter]})
@@ -110,7 +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)
 	}
 }
@@ -124,7 +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
 
@@ -144,7 +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.ExtensionsV1beta1().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"
@@ -10,7 +11,7 @@ import (
 	appsv1 "k8s.io/api/apps/v1"
 	autoscalingv2 "k8s.io/api/autoscaling/v2beta2"
 	corev1 "k8s.io/api/core/v1"
-	"k8s.io/api/extensions/v1beta1"
+	v1beta1 "k8s.io/api/networking/v1beta1"
 	"k8s.io/apimachinery/pkg/api/resource"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/client-go/kubernetes"
@@ -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.ExtensionsV1beta1().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/provider/metric_store.go

@@ -69,9 +69,15 @@ func (s *MetricStore) insertCustomMetric(value custom_metrics.MetricValue) {
 			Resource: "pods",
 		}
 	case "Ingress":
+		// group can be either `extentions` or `networking.k8s.io`
+		group := "extensions"
+		gv, err := schema.ParseGroupVersion(value.DescribedObject.APIVersion)
+		if err == nil {
+			group = gv.Group
+		}
 		groupResource = schema.GroupResource{
 			Resource: "ingresses",
-			Group:    "extensions",
+			Group:    group,
 		}
 	}
 

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"
+)