Update dependencies

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

.github/CODEOWNERS

@@ -1,35 +0,0 @@
-# These owners will be the default owners for everything in
-# the repo. 
-*       @arjunrn
-
-
-
-# Samples for assigning codeowners below:
-# Order is important; the last matching pattern takes the most
-# precedence. When someone opens a pull request that only
-# modifies JS files, only @js-owner and not the global
-# owner(s) will be requested for a review.
-# *.js    @js-owner
-
-# You can also use email addresses if you prefer. They'll be
-# used to look up users just like we do for commit author
-# emails.
-# *.go docs@example.com
-
-# In this example, @doctocat owns any files in the build/logs
-# directory at the root of the repository and any of its
-# subdirectories.
-# /build/logs/ @doctocat
-
-# The `docs/*` pattern will match files like
-# `docs/getting-started.md` but not further nested files like
-# `docs/build-app/troubleshooting.md`.
-# docs/*  docs@example.com
-
-# In this example, @octocat owns any file in an apps directory
-# anywhere in your repository.
-# apps/ @octocat
-
-# In this example, @doctocat owns any file in the `/docs`
-# directory in the root of your repository.
-# /docs/ @doctocat

.github/dependabot.yml

@@ -0,0 +1,14 @@
+version: 2
+updates:
+- package-ecosystem: gomod
+  directory: "/"
+  schedule:
+    interval: monthly
+    time: "07:00"
+  open-pull-requests-limit: 10
+- package-ecosystem: docker
+  directory: "/"
+  schedule:
+    interval: monthly
+    time: "07:00"
+  open-pull-requests-limit: 10

MAINTAINERS

@@ -1,3 +1,2 @@
 Mikkel Larsen <mikkel.larsen@zalando.de>
-Arjun Naik <arjun.naik@zalando.de>
 Team Teapot <team-teapot@zalando.de>

Makefile

@@ -8,12 +8,15 @@ SOURCES       = $(shell find . -name '*.go')
 DOCKERFILE    ?= Dockerfile
 GOPKGS        = $(shell go list ./...)
 BUILD_FLAGS   ?= -v
+OPENAPI       ?= pkg/api/generated/openapi/zz_generated.openapi.go
 LDFLAGS       ?= -X main.version=$(VERSION) -w -s
 
+
 default: build.local
 
 clean:
 	rm -rf build
+	rm -rf $(OPENAPI)
 
 test:
 	go test -v $(GOPKGS)
@@ -22,17 +25,28 @@ check:
 	go mod download
 	golangci-lint run --timeout=2m ./...
 
+
+$(OPENAPI): go.mod
+	go run k8s.io/kube-openapi/cmd/openapi-gen \
+		--go-header-file hack/boilerplate.go.txt \
+		--logtostderr \
+		-i k8s.io/metrics/pkg/apis/custom_metrics,k8s.io/metrics/pkg/apis/custom_metrics/v1beta1,k8s.io/metrics/pkg/apis/custom_metrics/v1beta2,k8s.io/metrics/pkg/apis/external_metrics,k8s.io/metrics/pkg/apis/external_metrics/v1beta1,k8s.io/metrics/pkg/apis/metrics,k8s.io/metrics/pkg/apis/metrics/v1beta1,k8s.io/apimachinery/pkg/apis/meta/v1,k8s.io/apimachinery/pkg/api/resource,k8s.io/apimachinery/pkg/version,k8s.io/api/core/v1 \
+		-p pkg/api/generated/openapi \
+		-o . \
+		-O zz_generated.openapi \
+		-r /dev/null
+
 build.local: build/$(BINARY)
 build.linux: build/linux/$(BINARY)
 build.osx: build/osx/$(BINARY)
 
-build/$(BINARY): go.mod $(SOURCES)
+build/$(BINARY): go.mod $(SOURCES) $(OPENAPI)
 	CGO_ENABLED=0 go build -o build/$(BINARY) $(BUILD_FLAGS) -ldflags "$(LDFLAGS)" .
 
-build/linux/$(BINARY): go.mod $(SOURCES)
+build/linux/$(BINARY): go.mod $(SOURCES) $(OPENAPI)
 	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 $(SOURCES) $(OPENAPI)
 	GOOS=darwin GOARCH=amd64 CGO_ENABLED=0 go build $(BUILD_FLAGS) -o build/osx/$(BINARY) -ldflags "$(LDFLAGS)" .
 
 build.docker: build.linux

README.md

@@ -142,7 +142,7 @@ example the following JSON data would be expected:
 ```
 
 The json-path query support depends on the
-[github.com/oliveagle/jsonpath](https://github.com/oliveagle/jsonpath) library.
+[github.com/spyzhov/ajson](https://github.com/spyzhov/ajson) library.
 See the README for possible queries. It's expected that the metric you query
 returns something that can be turned into a `float64`.
 
@@ -202,6 +202,16 @@ the trade-offs between the two approaches.
 | `prometheus-query` | Generic metric which requires a user defined query. | External | | `>=1.12` |
 | *custom* | No predefined metrics. Metrics are generated from user defined queries. | Object | *any* | `>=1.12` |
 
+### Configure Scrape Interval
+
+There is a way to set the interval via an annotation like:
+
+```yaml
+metric-config.external.prometheus-query.prometheus/interval: 30s
+```
+
+Default is 1 minute.
+
 ### Example: External Metric
 
 This is an example of an HPA configured to get metrics based on a Prometheus

go.mod

@@ -2,31 +2,36 @@ module github.com/zalando-incubator/kube-metrics-adapter
 
 require (
 	github.com/NYTimes/gziphandler v1.0.1 // indirect
-	github.com/aws/aws-sdk-go v1.30.24
+	github.com/aws/aws-sdk-go v1.35.19
+	github.com/go-openapi/spec v0.19.12
 	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 v0.0.0-20201023074945-51cc7b53320e
 	github.com/lib/pq v1.2.0 // indirect
+	github.com/mailru/easyjson v0.7.6 // 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 v0.9.1
-	github.com/sirupsen/logrus v1.6.0
+	github.com/prometheus/client_golang v1.8.0
+	github.com/prometheus/common v0.14.0
+	github.com/sirupsen/logrus v1.7.0
 	github.com/spf13/cobra v0.0.7
-	github.com/stretchr/testify v1.5.1
+	github.com/spyzhov/ajson v0.4.2
+	github.com/stretchr/testify v1.6.1
 	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/net v0.0.0-20201031054903-ff519b6c9102 // indirect
 	golang.org/x/oauth2 v0.0.0-20190604053449-0f29369cfe45
+	golang.org/x/text v0.3.4 // indirect
 	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 v0.18.8
+	k8s.io/apimachinery v0.18.8
+	k8s.io/apiserver v0.18.8
+	k8s.io/client-go v0.18.8
+	k8s.io/component-base v0.18.8
 	k8s.io/klog v1.0.0
-	k8s.io/metrics v0.17.3
+	k8s.io/kube-openapi v0.0.0-20200410145947-61e04a5be9a6
+	k8s.io/metrics v0.18.8
 )
 
-go 1.13
+go 1.15

hack/boilerplate.go.txt

@@ -0,0 +1,16 @@
+/*
+Copyright 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.
+*/
+

hack/tools.go

@@ -0,0 +1,6 @@
+// +build tools
+
+// This package imports things required by build scripts, to force `go mod` to see them as dependencies
+package tools
+
+import _ "k8s.io/kube-openapi/cmd/openapi-gen"

pkg/collector/http_collector.go

@@ -7,7 +7,6 @@ import (
 
 	"github.com/zalando-incubator/kube-metrics-adapter/pkg/collector/httpmetrics"
 
-	"github.com/oliveagle/jsonpath"
 	"k8s.io/api/autoscaling/v2beta2"
 	"k8s.io/apimachinery/pkg/api/resource"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
@@ -36,14 +35,12 @@ func (p *HTTPCollectorPlugin) NewCollector(_ *v2beta2.HorizontalPodAutoscaler, c
 	if value, ok = config.Config[HTTPJsonPathAnnotationKey]; !ok {
 		return nil, fmt.Errorf("config value %s not found", HTTPJsonPathAnnotationKey)
 	}
-	jsonPath, err := jsonpath.Compile(value)
-	if err != nil {
-		return nil, fmt.Errorf("failed to parse json path: %v", err)
-	}
-	collector.jsonPath = jsonPath
+	jsonPath := value
+
 	if value, ok = config.Config[HTTPEndpointAnnotationKey]; !ok {
 		return nil, fmt.Errorf("config value %s not found", HTTPEndpointAnnotationKey)
 	}
+	var err error
 	collector.endpoint, err = url.Parse(value)
 	if err != nil {
 		return nil, err
@@ -65,13 +62,16 @@ func (p *HTTPCollectorPlugin) NewCollector(_ *v2beta2.HorizontalPodAutoscaler, c
 			return nil, err
 		}
 	}
-	collector.metricsGetter = httpmetrics.NewJSONPathMetricsGetter(httpmetrics.DefaultMetricsHTTPClient(), aggFunc, jsonPath)
+	jsonPathGetter, err := httpmetrics.NewJSONPathMetricsGetter(httpmetrics.DefaultMetricsHTTPClient(), aggFunc, jsonPath)
+	if err != nil {
+		return nil, err
+	}
+	collector.metricsGetter = jsonPathGetter
 	return collector, nil
 }
 
 type HTTPCollector struct {
 	endpoint      *url.URL
-	jsonPath      *jsonpath.Compiled
 	interval      time.Duration
 	metricType    v2beta2.MetricSourceType
 	metricsGetter *httpmetrics.JSONPathMetricsGetter

pkg/collector/httpmetrics/json_path.go

@@ -1,7 +1,6 @@
 package httpmetrics
 
 import (
-	"encoding/json"
 	"fmt"
 	"io/ioutil"
 	"net"
@@ -9,21 +8,26 @@ import (
 	"net/url"
 	"time"
 
-	"github.com/oliveagle/jsonpath"
+	"github.com/spyzhov/ajson"
 )
 
 // JSONPathMetricsGetter is a metrics getter which looks up pod metrics by
 // querying the pods metrics endpoint and lookup the metric value as defined by
 // the json path query.
 type JSONPathMetricsGetter struct {
-	jsonPath   *jsonpath.Compiled
+	jsonPath   string
 	aggregator AggregatorFunc
 	client     *http.Client
 }
 
 // NewJSONPathMetricsGetter initializes a new JSONPathMetricsGetter.
-func NewJSONPathMetricsGetter(httpClient *http.Client, aggregatorFunc AggregatorFunc, compiledPath *jsonpath.Compiled) *JSONPathMetricsGetter {
-	return &JSONPathMetricsGetter{client: httpClient, aggregator: aggregatorFunc, jsonPath: compiledPath}
+func NewJSONPathMetricsGetter(httpClient *http.Client, aggregatorFunc AggregatorFunc, jsonPath string) (*JSONPathMetricsGetter, error) {
+	// check that jsonPath parses
+	_, err := ajson.ParseJSONPath(jsonPath)
+	if err != nil {
+		return nil, err
+	}
+	return &JSONPathMetricsGetter{client: httpClient, aggregator: aggregatorFunc, jsonPath: jsonPath}, nil
 }
 
 var DefaultRequestTimeout = 15 * time.Second
@@ -58,57 +62,45 @@ func (g *JSONPathMetricsGetter) GetMetric(metricsURL url.URL) (float64, error) {
 	}
 
 	// parse data
-	var jsonData interface{}
-	err = json.Unmarshal(data, &jsonData)
+	root, err := ajson.Unmarshal(data)
 	if err != nil {
 		return 0, err
 	}
 
-	res, err := g.jsonPath.Lookup(jsonData)
+	nodes, err := root.JSONPath(g.jsonPath)
 	if err != nil {
 		return 0, err
 	}
 
-	switch res := res.(type) {
-	case int:
-		return float64(res), nil
-	case float32:
-		return float64(res), nil
-	case float64:
-		return res, nil
-	case []interface{}:
+	if len(nodes) != 1 {
+		return 0, fmt.Errorf("unexpected json: expected single numeric or array value")
+	}
+
+	node := nodes[0]
+	if node.IsArray() {
 		if g.aggregator == nil {
 			return 0, fmt.Errorf("no aggregator function has been specified")
 		}
-		s, err := castSlice(res)
-		if err != nil {
-			return 0, err
-		}
-		return g.aggregator(s...), nil
-	default:
-		return 0, fmt.Errorf("unsupported type %T", res)
-	}
-}
-
-// castSlice takes a slice of interface and returns a slice of float64 if all
-// values in slice were castable, else returns an error
-func castSlice(in []interface{}) ([]float64, error) {
-	var out []float64
-
-	for _, v := range in {
-		switch v := v.(type) {
-		case int:
-			out = append(out, float64(v))
-		case float32:
-			out = append(out, float64(v))
-		case float64:
-			out = append(out, v)
-		default:
-			return nil, fmt.Errorf("slice was returned by JSONPath, but value inside is unsupported: %T", v)
+		values := make([]float64, 0, len(nodes))
+		items, _ := node.GetArray()
+		for _, item := range items {
+			value, err := item.GetNumeric()
+			if err != nil {
+				return 0, fmt.Errorf("did not find numeric type: %w", err)
+			}
+			values = append(values, value)
 		}
+		return g.aggregator(values...), nil
+	} else if node.IsNumeric() {
+		res, _ := node.GetNumeric()
+		return res, nil
 	}
 
-	return out, nil
+	value, err := node.Value()
+	if err != nil {
+		return 0, fmt.Errorf("failed to check value of jsonPath result: %w", err)
+	}
+	return 0, fmt.Errorf("unsupported type %T", value)
 }
 
 func (g *JSONPathMetricsGetter) fetchMetrics(metricsURL url.URL) ([]byte, error) {

pkg/collector/httpmetrics/json_path_test.go

@@ -1,59 +1,21 @@
 package httpmetrics
 
 import (
-	"encoding/json"
+	"errors"
 	"fmt"
 	"net/http"
 	"net/http/httptest"
 	"net/url"
 	"testing"
 
-	"github.com/oliveagle/jsonpath"
 	"github.com/stretchr/testify/require"
 )
 
-func TestCastSlice(t *testing.T) {
-	res1, err1 := castSlice([]interface{}{1, 2, 3})
-	require.NoError(t, err1)
-	require.Equal(t, []float64{1.0, 2.0, 3.0}, res1)
-
-	res2, err2 := castSlice([]interface{}{float32(1.0), float32(2.0), float32(3.0)})
-	require.NoError(t, err2)
-	require.Equal(t, []float64{1.0, 2.0, 3.0}, res2)
-
-	res3, err3 := castSlice([]interface{}{float64(1.0), float64(2.0), float64(3.0)})
-	require.NoError(t, err3)
-	require.Equal(t, []float64{1.0, 2.0, 3.0}, res3)
-
-	res4, err4 := castSlice([]interface{}{1, 2, "some string"})
-	require.Errorf(t, err4, "slice was returned by JSONPath, but value inside is unsupported: %T", "string")
-	require.Equal(t, []float64(nil), res4)
-}
-
-type testValueResponse struct {
-	Value int64 `json:"value"`
-}
-
-type testValueArrayResponse struct {
-	Value []int64 `json:"value"`
-}
-
-func makeTestHTTPServer(t *testing.T, values ...int64) *httptest.Server {
+func makeTestHTTPServer(t *testing.T, response []byte) *httptest.Server {
 	h := func(w http.ResponseWriter, r *http.Request) {
 		require.Equal(t, r.URL.Path, "/metrics")
 		w.Header().Set("Content-Type", "application/json")
-		var (
-			response []byte
-			err      error
-		)
-		if len(values) == 1 {
-			response, err = json.Marshal(testValueResponse{Value: values[0]})
-			require.NoError(t, err)
-		} else {
-			response, err = json.Marshal(testValueArrayResponse{Value: values})
-			require.NoError(t, err)
-		}
-		_, err = w.Write(response)
+		_, err := w.Write(response)
 		require.NoError(t, err)
 	}
 	return httptest.NewServer(http.HandlerFunc(h))
@@ -61,29 +23,62 @@ func makeTestHTTPServer(t *testing.T, values ...int64) *httptest.Server {
 
 func TestJSONPathMetricsGetter(t *testing.T) {
 	for _, tc := range []struct {
-		name       string
-		input      []int64
-		output     float64
-		aggregator AggregatorFunc
+		name         string
+		jsonResponse []byte
+		jsonPath     string
+		result       float64
+		aggregator   AggregatorFunc
+		err          error
 	}{
 		{
-			name:       "basic average",
-			input:      []int64{3, 4, 5},
-			output:     4,
-			aggregator: Average,
+			name:         "basic single value",
+			jsonResponse: []byte(`{"value":3}`),
+			jsonPath:     "$.value",
+			result:       3,
+			aggregator:   Average,
+		},
+		{
+			name:         "basic average",
+			jsonResponse: []byte(`{"value":[3,4,5]}`),
+			jsonPath:     "$.value",
+			result:       4,
+			aggregator:   Average,
+		},
+		{
+			name:         "dotted key",
+			jsonResponse: []byte(`{"metric.value":5}`),
+			jsonPath:     "$['metric.value']",
+			result:       5,
+			aggregator:   Average,
+		},
+		{
+			name:         "json path not resulting in array or number should lead to error",
+			jsonResponse: []byte(`{"metric.value":5}`),
+			jsonPath:     "$['invalid.metric.values']",
+			err:          errors.New("unexpected json: expected single numeric or array value"),
+		},
+		{
+			name:         "invalid json should error",
+			jsonResponse: []byte(`{`),
+			jsonPath:     "$['invalid.metric.values']",
+			err:          errors.New("unexpected end of file"),
 		},
 	} {
 		t.Run(tc.name, func(t *testing.T) {
-			server := makeTestHTTPServer(t, tc.input...)
+			server := makeTestHTTPServer(t, tc.jsonResponse)
 			defer server.Close()
-			path, err := jsonpath.Compile("$.value")
+			getter, err := NewJSONPathMetricsGetter(DefaultMetricsHTTPClient(), tc.aggregator, tc.jsonPath)
 			require.NoError(t, err)
-			getter := NewJSONPathMetricsGetter(DefaultMetricsHTTPClient(), tc.aggregator, path)
 			url, err := url.Parse(fmt.Sprintf("%s/metrics", server.URL))
 			require.NoError(t, err)
 			metric, err := getter.GetMetric(*url)
+			if tc.err != nil {
+				require.Error(t, err)
+				require.Equal(t, tc.err.Error(), err.Error())
+				return
+			}
 			require.NoError(t, err)
-			require.Equal(t, tc.output, metric)
+			require.Equal(t, tc.result, metric)
 		})
 	}
 }

pkg/collector/httpmetrics/pod_metrics.go

@@ -6,7 +6,6 @@ import (
 	"strconv"
 	"time"
 
-	"github.com/oliveagle/jsonpath"
 	v1 "k8s.io/api/core/v1"
 )
 
@@ -33,18 +32,13 @@ func (g PodMetricsJSONPathGetter) GetMetric(pod *v1.Pod) (float64, error) {
 func NewPodMetricsJSONPathGetter(config map[string]string) (*PodMetricsJSONPathGetter, error) {
 	getter := PodMetricsJSONPathGetter{}
 	var (
-		jsonPath   *jsonpath.Compiled
+		jsonPath   string
 		aggregator AggregatorFunc
 		err        error
 	)
 
 	if v, ok := config["json-key"]; ok {
-		path, err := jsonpath.Compile(v)
-		if err != nil {
-			return nil, fmt.Errorf("failed to parse json path definition: %v", err)
-		}
-
-		jsonPath = path
+		jsonPath = v
 	}
 
 	if v, ok := config["scheme"]; ok {
@@ -99,7 +93,11 @@ func NewPodMetricsJSONPathGetter(config map[string]string) (*PodMetricsJSONPathG
 		connectTimeout = d
 	}
 
-	getter.metricGetter = NewJSONPathMetricsGetter(CustomMetricsHTTPClient(requestTimeout, connectTimeout), aggregator, jsonPath)
+	jsonPathGetter, err := NewJSONPathMetricsGetter(CustomMetricsHTTPClient(requestTimeout, connectTimeout), aggregator, jsonPath)
+	if err != nil {
+		return nil, err
+	}
+	getter.metricGetter = jsonPathGetter
 	return &getter, nil
 }
 

pkg/collector/httpmetrics/pod_metrics_test.go

@@ -5,7 +5,6 @@ import (
 	"testing"
 	"time"
 
-	"github.com/oliveagle/jsonpath"
 	"github.com/stretchr/testify/require"
 )
 
@@ -23,12 +22,11 @@ func TestNewPodJSONPathMetricsGetter(t *testing.T) {
 		"path":     "/metrics",
 		"port":     "9090",
 	}
-	jpath1, _ := jsonpath.Compile(configNoAggregator["json-key"])
 	getterNoAggregator, err1 := NewPodMetricsJSONPathGetter(configNoAggregator)
 
 	require.NoError(t, err1)
 	compareMetricsGetter(t, &PodMetricsJSONPathGetter{
-		metricGetter: &JSONPathMetricsGetter{jsonPath: jpath1},
+		metricGetter: &JSONPathMetricsGetter{jsonPath: configNoAggregator["json-key"]},
 		scheme:       "http",
 		path:         "/metrics",
 		port:         9090,
@@ -41,12 +39,11 @@ func TestNewPodJSONPathMetricsGetter(t *testing.T) {
 		"port":       "9090",
 		"aggregator": "avg",
 	}
-	jpath2, _ := jsonpath.Compile(configAggregator["json-key"])
 	getterAggregator, err2 := NewPodMetricsJSONPathGetter(configAggregator)
 
 	require.NoError(t, err2)
 	compareMetricsGetter(t, &PodMetricsJSONPathGetter{
-		metricGetter: &JSONPathMetricsGetter{jsonPath: jpath2, aggregator: Average},
+		metricGetter: &JSONPathMetricsGetter{jsonPath: configAggregator["json-key"], aggregator: Average},
 		scheme:       "http",
 		path:         "/metrics",
 		port:         9090,
@@ -79,12 +76,11 @@ func TestNewPodJSONPathMetricsGetter(t *testing.T) {
 		"port":      "9090",
 		"raw-query": "foo=bar&baz=bop",
 	}
-	jpath5, _ := jsonpath.Compile(configWithRawQuery["json-key"])
 	getterWithRawQuery, err5 := NewPodMetricsJSONPathGetter(configWithRawQuery)
 
 	require.NoError(t, err5)
 	compareMetricsGetter(t, &PodMetricsJSONPathGetter{
-		metricGetter: &JSONPathMetricsGetter{jsonPath: jpath5},
+		metricGetter: &JSONPathMetricsGetter{jsonPath: configWithRawQuery["json-key"]},
 		scheme:       "http",
 		path:         "/metrics",
 		port:         9090,
@@ -107,8 +103,6 @@ func TestBuildMetricsURL(t *testing.T) {
 		"port":      port,
 		"raw-query": rawQuery,
 	}
-	_, err := jsonpath.Compile(configWithRawQuery["json-key"])
-	require.NoError(t, err)
 	getterWithRawQuery, err1 := NewPodMetricsJSONPathGetter(configWithRawQuery)
 	require.NoError(t, err1)
 
@@ -123,8 +117,6 @@ func TestBuildMetricsURL(t *testing.T) {
 		"path":     path,
 		"port":     port,
 	}
-	_, err2 := jsonpath.Compile(configWithNoQuery["json-key"])
-	require.NoError(t, err2)
 	getterWithNoQuery, err3 := NewPodMetricsJSONPathGetter(configWithNoQuery)
 	require.NoError(t, err3)
 
@@ -140,10 +132,10 @@ func TestCustomTimeouts(t *testing.T) {
 
 	// Test no custom options results in default timeouts
 	defaultConfig := map[string]string{
-		"json-key":  "$.value",
-		"scheme":    scheme,
-		"path":      path,
-		"port":      port,
+		"json-key": "$.value",
+		"scheme":   scheme,
+		"path":     path,
+		"port":     port,
 	}
 	defaultTime := time.Duration(15000) * time.Millisecond
 
@@ -153,10 +145,10 @@ func TestCustomTimeouts(t *testing.T) {
 
 	// Test with custom request timeout
 	configWithRequestTimeout := map[string]string{
-		"json-key":  "$.value",
-		"scheme":    scheme,
-		"path":      path,
-		"port":      port,
+		"json-key":        "$.value",
+		"scheme":          scheme,
+		"path":            path,
+		"port":            port,
 		"request-timeout": "978ms",
 	}
 	exectedTimeout := time.Duration(978) * time.Millisecond
@@ -167,30 +159,30 @@ func TestCustomTimeouts(t *testing.T) {
 	// 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":  "$.value",
-		"scheme":    scheme,
-		"path":      path,
-		"port":      port,
+		"json-key":        "$.value",
+		"scheme":          scheme,
+		"path":            path,
+		"port":            port,
 		"connect-timeout": "512ms",
 	}
-	customRequestGetter, err3 := NewPodMetricsJSONPathGetter(configWithConnectTimeout)
+	_, err3 := NewPodMetricsJSONPathGetter(configWithConnectTimeout)
 	require.NoError(t, err3)
 
 	configWithInvalidTimeout := map[string]string{
-		"json-key":  "$.value",
-		"scheme":    scheme,
-		"path":      path,
-		"port":      port,
+		"json-key":        "$.value",
+		"scheme":          scheme,
+		"path":            path,
+		"port":            port,
 		"request-timeout": "-256ms",
 	}
 	_, err4 := NewPodMetricsJSONPathGetter(configWithInvalidTimeout)
 	require.Error(t, err4)
 
 	configWithInvalidTimeout = map[string]string{
-		"json-key":  "$.value",
-		"scheme":    scheme,
-		"path":      path,
-		"port":      port,
+		"json-key":        "$.value",
+		"scheme":          scheme,
+		"path":            path,
+		"port":            port,
 		"connect-timeout": "-256ms",
 	}
 	_, err5 := NewPodMetricsJSONPathGetter(configWithInvalidTimeout)

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"
@@ -87,16 +88,16 @@ func NewSkipperCollector(client kubernetes.Interface, plugin CollectorPlugin, hp
 	}, nil
 }
 
-func getAnnotationWeight(backendWeights string, backend string) float64 {
-	var weightsMap map[string]int
+func getAnnotationWeight(backendWeights string, backend string) (float64, error) {
+	var weightsMap map[string]float64
 	err := json.Unmarshal([]byte(backendWeights), &weightsMap)
 	if err != nil {
-		return 0
+		return 0, err
 	}
 	if weight, ok := weightsMap[backend]; ok {
-		return float64(weight) / 100
+		return float64(weight) / 100, nil
 	}
-	return 0
+	return 0, nil
 }
 
 func getWeights(ingressAnnotations map[string]string, backendAnnotations []string, backend string) (float64, error) {
@@ -106,7 +107,11 @@ func getWeights(ingressAnnotations map[string]string, backendAnnotations []strin
 	for _, anno := range backendAnnotations {
 		if weightsMap, ok := ingressAnnotations[anno]; ok {
 			annotationsPresent = true
-			maxWeight = math.Max(maxWeight, getAnnotationWeight(weightsMap, backend))
+			weight, err := getAnnotationWeight(weightsMap, backend)
+			if err != nil {
+				return 0.0, err
+			}
+			maxWeight = math.Max(maxWeight, weight)
 		}
 	}
 
@@ -125,7 +130,7 @@ 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 +212,13 @@ 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) {
@@ -111,7 +112,7 @@ func TestSkipperCollector(t *testing.T) {
 		expectError        bool
 		fakedAverage       bool
 		namespace          string
-		backendWeights     map[string]map[string]int
+		backendWeights     map[string]map[string]float64
 		replicas           int32
 		readyReplicas      int32
 		backendAnnotations []string
@@ -137,7 +138,7 @@ func TestSkipperCollector(t *testing.T) {
 			collectedMetric:    1000,
 			namespace:          "default",
 			backend:            "backend1",
-			backendWeights:     map[string]map[string]int{testBackendWeightsAnnotation: {"backend2": 60, "backend1": 40}},
+			backendWeights:     map[string]map[string]float64{testBackendWeightsAnnotation: {"backend2": 60.0, "backend1": 40}},
 			replicas:           1,
 			readyReplicas:      1,
 			backendAnnotations: []string{testBackendWeightsAnnotation},
@@ -151,7 +152,7 @@ func TestSkipperCollector(t *testing.T) {
 			collectedMetric:    1000,
 			namespace:          "default",
 			backend:            "backend1",
-			backendWeights:     map[string]map[string]int{testBackendWeightsAnnotation: {"backend2": 60, "backend1": 40}},
+			backendWeights:     map[string]map[string]float64{testBackendWeightsAnnotation: {"backend2": 60, "backend1": 40}},
 			replicas:           1,
 			readyReplicas:      1,
 			backendAnnotations: []string{testBackendWeightsAnnotation},
@@ -166,7 +167,7 @@ func TestSkipperCollector(t *testing.T) {
 			fakedAverage:       true,
 			namespace:          "default",
 			backend:            "backend1",
-			backendWeights:     map[string]map[string]int{testBackendWeightsAnnotation: {"backend2": 50, "backend1": 50}},
+			backendWeights:     map[string]map[string]float64{testBackendWeightsAnnotation: {"backend2": 50, "backend1": 50}},
 			replicas:           5,
 			readyReplicas:      5,
 			backendAnnotations: []string{testBackendWeightsAnnotation},
@@ -180,7 +181,7 @@ func TestSkipperCollector(t *testing.T) {
 			collectedMetric:    1500,
 			namespace:          "default",
 			backend:            "backend1",
-			backendWeights:     map[string]map[string]int{testBackendWeightsAnnotation: {"backend2": 50, "backend1": 50}},
+			backendWeights:     map[string]map[string]float64{testBackendWeightsAnnotation: {"backend2": 50, "backend1": 50}},
 			replicas:           5, // this is not taken into account
 			readyReplicas:      5,
 			backendAnnotations: []string{testBackendWeightsAnnotation},
@@ -194,7 +195,7 @@ func TestSkipperCollector(t *testing.T) {
 			collectedMetric:    0,
 			namespace:          "default",
 			backend:            "backend1",
-			backendWeights:     map[string]map[string]int{testBackendWeightsAnnotation: {"backend2": 100, "backend1": 0}},
+			backendWeights:     map[string]map[string]float64{testBackendWeightsAnnotation: {"backend2": 100, "backend1": 0}},
 			replicas:           5,
 			readyReplicas:      5,
 			backendAnnotations: []string{testBackendWeightsAnnotation},
@@ -209,7 +210,7 @@ func TestSkipperCollector(t *testing.T) {
 			fakedAverage:    true,
 			namespace:       "default",
 			backend:         "backend1",
-			backendWeights: map[string]map[string]int{
+			backendWeights: map[string]map[string]float64{
 				testBackendWeightsAnnotation:  {"backend2": 20, "backend1": 80},
 				testStacksetWeightsAnnotation: {"backend2": 0, "backend1": 100},
 			},
@@ -226,7 +227,7 @@ func TestSkipperCollector(t *testing.T) {
 			collectedMetric: 1500,
 			namespace:       "default",
 			backend:         "backend1",
-			backendWeights: map[string]map[string]int{
+			backendWeights: map[string]map[string]float64{
 				testBackendWeightsAnnotation:  {"backend2": 20, "backend1": 80},
 				testStacksetWeightsAnnotation: {"backend2": 0, "backend1": 100},
 			},
@@ -243,7 +244,7 @@ func TestSkipperCollector(t *testing.T) {
 			collectedMetric:    0,
 			namespace:          "default",
 			backend:            "backend3",
-			backendWeights:     map[string]map[string]int{testBackendWeightsAnnotation: {"backend2": 100, "backend1": 0}},
+			backendWeights:     map[string]map[string]float64{testBackendWeightsAnnotation: {"backend2": 100, "backend1": 0}},
 			replicas:           1,
 			readyReplicas:      1,
 			backendAnnotations: []string{testBackendWeightsAnnotation},
@@ -257,7 +258,7 @@ func TestSkipperCollector(t *testing.T) {
 			collectedMetric:    1500,
 			namespace:          "default",
 			backend:            "backend3",
-			backendWeights:     map[string]map[string]int{},
+			backendWeights:     map[string]map[string]float64{},
 			replicas:           1,
 			readyReplicas:      1,
 			backendAnnotations: []string{testBackendWeightsAnnotation},
@@ -271,7 +272,7 @@ func TestSkipperCollector(t *testing.T) {
 			expectError:        true,
 			namespace:          "default",
 			backend:            "",
-			backendWeights:     map[string]map[string]int{testBackendWeightsAnnotation: {"backend2": 100, "backend1": 0}},
+			backendWeights:     map[string]map[string]float64{testBackendWeightsAnnotation: {"backend2": 100, "backend1": 0}},
 			replicas:           1,
 			readyReplicas:      1,
 			backendAnnotations: []string{testBackendWeightsAnnotation},
@@ -300,7 +301,7 @@ func TestSkipperCollector(t *testing.T) {
 			fakedAverage:    true,
 			namespace:       "default",
 			backend:         "backend2",
-			backendWeights: map[string]map[string]int{
+			backendWeights: map[string]map[string]float64{
 				testBackendWeightsAnnotation:  {"backend2": 20, "backend1": 80},
 				testStacksetWeightsAnnotation: {"backend1": 100},
 			},
@@ -313,12 +314,12 @@ func TestSkipperCollector(t *testing.T) {
 			metric:          1500,
 			ingressName:     "dummy-ingress",
 			hostnames:       []string{"example.org"},
-			expectedQuery:   `scalar(sum(rate(skipper_serve_host_duration_seconds_count{host=~"example_org"}[1m])) * 0.2000)`,
+			expectedQuery:   `scalar(sum(rate(skipper_serve_host_duration_seconds_count{host=~"example_org"}[1m])) * 0.2050)`,
 			collectedMetric: 1500,
 			namespace:       "default",
 			backend:         "backend2",
-			backendWeights: map[string]map[string]int{
-				testBackendWeightsAnnotation:  {"backend2": 20, "backend1": 80},
+			backendWeights: map[string]map[string]float64{
+				testBackendWeightsAnnotation:  {"backend2": 20.5, "backend1": 79.5},
 				testStacksetWeightsAnnotation: {"backend1": 100},
 			},
 			replicas:           5,
@@ -351,7 +352,7 @@ func TestSkipperCollector(t *testing.T) {
 	}
 }
 
-func makeIngress(client kubernetes.Interface, namespace, ingressName, backend string, hostnames []string, backendWeights map[string]map[string]int) error {
+func makeIngress(client kubernetes.Interface, namespace, ingressName, backend string, hostnames []string, backendWeights map[string]map[string]float64) error {
 	annotations := make(map[string]string)
 	for anno, weights := range backendWeights {
 		sWeights, err := json.Marshal(weights)
@@ -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

@@ -25,14 +25,18 @@ import (
 
 	"github.com/aws/aws-sdk-go/aws"
 	"github.com/aws/aws-sdk-go/aws/session"
+	"github.com/kubernetes-incubator/custom-metrics-apiserver/pkg/apiserver"
 	"github.com/kubernetes-incubator/custom-metrics-apiserver/pkg/cmd/server"
 	"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/api/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"
+	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}