#10 HPA feat - initial version for OBI metrics adapter

Makefile

@@ -45,6 +45,10 @@ update:
 verify:
 	@hack/verify-all.sh
 
+.PHONY: golanglint-fix
+golanglint-fix:
+	@hack/fix-golang-lint-error.sh
+
 # Build image.
 #
 # Args:

build/dockerfile.metrics-adapter

@@ -0,0 +1,19 @@
+# Build the application
+FROM golang:1.19 as builder
+
+WORKDIR /go/src/github.com/kube-arbiter/arbiter
+COPY . .
+
+#RUN go get -d -v
+
+RUN CGO_ENABLED=0 GOOS=linux go build -a -installsuffix cgo -o obi-metrics-adapter cmd/obi-adapter/main.go
+
+# Run the application
+FROM alpine:latest
+
+# RUN apk --no-cache add ca-certificates
+
+WORKDIR /root/
+COPY --from=builder /go/src/github.com/kube-arbiter/arbiter/obi-metrics-adapter .
+
+ENTRYPOINT ["./obi-metrics-adapter"]

cmd/obi-adapter/main.go

@@ -0,0 +1,108 @@
+/*
+Copyright 2022 The Arbiter 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.
+*/
+
+package main
+
+import (
+	"flag"
+	"fmt"
+	"os"
+
+	openapinamer "k8s.io/apiserver/pkg/endpoints/openapi"
+	genericapiserver "k8s.io/apiserver/pkg/server"
+	"k8s.io/component-base/logs"
+	"k8s.io/klog/v2"
+	customexternalmetrics "sigs.k8s.io/custom-metrics-apiserver/pkg/apiserver"
+	basecmd "sigs.k8s.io/custom-metrics-apiserver/pkg/cmd"
+	"sigs.k8s.io/custom-metrics-apiserver/pkg/provider"
+	"sigs.k8s.io/metrics-server/pkg/api"
+
+	emProvider "github.com/kube-arbiter/arbiter/pkg/adapter/provider"
+	generatedopenapi "github.com/kube-arbiter/arbiter/pkg/generated/api/generated/openapi"
+	"github.com/kube-arbiter/arbiter/pkg/generated/clientset/versioned"
+)
+
+type ArbiterAdapter struct {
+	basecmd.AdapterBase
+
+	// TODO: AdapterConfigFile points to the file containing the arbiter configuration.
+	AdapterConfigFile string
+}
+
+func (cmd *ArbiterAdapter) addFlags() {
+	cmd.Flags().StringVar(&cmd.AdapterConfigFile, "config", cmd.AdapterConfigFile,
+		"Configuration file containing details of how to transform between OBI metrics "+
+			"and custom metrics API resources")
+}
+
+func (cmd *ArbiterAdapter) makeProvider(stopCh <-chan struct{}) (provider.ExternalMetricsProvider, error) {
+	mapper, err := cmd.RESTMapper()
+	if err != nil {
+		return nil, fmt.Errorf("unable to construct RESTMapper: %v", err)
+	}
+	// Kubernetes client
+	restConfig, err := cmd.ClientConfig()
+	if err != nil {
+		return nil, fmt.Errorf("unable to construct Kubernetes rest client: %v", err)
+	}
+	kubeClient, err := versioned.NewForConfig(restConfig)
+	if err != nil {
+		return nil, fmt.Errorf("unable to construct Kubernetes versioned client: %v", err)
+	}
+	// construct the provider and start it
+	emProvider := emProvider.NewArbiterProvider(mapper, kubeClient)
+	return emProvider, nil
+}
+
+func main() {
+	logs.InitLogs()
+	defer logs.FlushLogs()
+
+	// set up flags
+	cmd := &ArbiterAdapter{}
+	cmd.Name = "obi-metrics-adapter"
+
+	cmd.OpenAPIConfig = genericapiserver.DefaultOpenAPIConfig(generatedopenapi.GetOpenAPIDefinitions, openapinamer.NewDefinitionNamer(api.Scheme, customexternalmetrics.Scheme))
+	cmd.OpenAPIConfig.Info.Title = "obi-metrics-adapter"
+	cmd.OpenAPIConfig.Info.Version = "0.2.0"
+
+	cmd.addFlags()
+	// make sure we get klog flags
+	local := flag.NewFlagSet(os.Args[0], flag.ExitOnError)
+	logs.AddGoFlags(local)
+	cmd.Flags().AddGoFlagSet(local)
+	if err := cmd.Flags().Parse(os.Args); err != nil {
+		klog.Fatalf("unable to parse flags: %v", err)
+	}
+
+	// stop channel closed on SIGTERM and SIGINT
+	stopCh := genericapiserver.SetupSignalHandler()
+
+	// construct the provider
+	emProvider, err := cmd.makeProvider(stopCh)
+	if err != nil {
+		klog.Fatalf("unable to construct custom metrics provider: %v", err)
+	}
+
+	// attach the provider to the server, if it's needed
+	if emProvider != nil {
+		cmd.WithExternalMetrics(emProvider)
+	}
+	// run the server
+	if err := cmd.Run(stopCh); err != nil {
+		klog.Fatalf("unable to run custom metrics adapter: %v", err)
+	}
+}

go.mod

@@ -18,13 +18,18 @@ require (
 	google.golang.org/protobuf v1.28.0
 	k8s.io/api v0.23.10
 	k8s.io/apimachinery v0.23.10
+	k8s.io/apiserver v0.23.10
 	k8s.io/cli-runtime v0.23.10
 	k8s.io/client-go v0.23.10
 	k8s.io/code-generator v0.23.10
 	k8s.io/component-base v0.23.10
-	k8s.io/klog/v2 v2.30.0
+	k8s.io/klog/v2 v2.40.1
+	k8s.io/kube-openapi v0.0.0-20220124234850-424119656bbf
 	k8s.io/kubernetes v1.23.10
+	k8s.io/metrics v0.23.10
 	sigs.k8s.io/controller-runtime v0.11.1
+	sigs.k8s.io/custom-metrics-apiserver v1.23.0
+	sigs.k8s.io/metrics-server v0.6.1
 )
 
 require (
@@ -73,7 +78,8 @@ require (
 	github.com/denis-tingaikin/go-header v0.4.3 // indirect
 	github.com/dlclark/regexp2 v1.7.0 // indirect
 	github.com/docker/distribution v2.7.1+incompatible // indirect
-	github.com/emicklei/go-restful v2.9.5+incompatible // indirect
+	github.com/emicklei/go-restful v2.15.0+incompatible // indirect
+	github.com/emicklei/go-restful-swagger12 v0.0.0-20201014110547-68ccff494617 // indirect
 	github.com/esimonov/ifshort v1.0.4 // indirect
 	github.com/ettle/strcase v0.1.1 // indirect
 	github.com/evanphx/json-patch v4.12.0+incompatible // indirect
@@ -89,8 +95,8 @@ require (
 	github.com/go-logr/logr v1.2.3 // indirect
 	github.com/go-logr/zapr v1.2.0 // indirect
 	github.com/go-openapi/jsonpointer v0.19.5 // indirect
-	github.com/go-openapi/jsonreference v0.19.5 // indirect
-	github.com/go-openapi/swag v0.19.14 // indirect
+	github.com/go-openapi/jsonreference v0.19.6 // indirect
+	github.com/go-openapi/swag v0.19.15 // indirect
 	github.com/go-sourcemap/sourcemap v2.1.3+incompatible // indirect
 	github.com/go-toolsmith/astcast v1.0.0 // indirect
 	github.com/go-toolsmith/astcopy v1.0.2 // indirect
@@ -270,15 +276,13 @@ require (
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 	honnef.co/go/tools v0.3.3 // indirect
 	k8s.io/apiextensions-apiserver v0.23.0 // indirect
-	k8s.io/apiserver v0.23.10 // indirect
 	k8s.io/cloud-provider v0.23.10 // indirect
 	k8s.io/component-helpers v0.23.10 // indirect
 	k8s.io/csi-translation-lib v0.23.10 // indirect
 	k8s.io/gengo v0.0.0-20210813121822-485abfe95c7c // indirect
-	k8s.io/kube-openapi v0.0.0-20211115234752-e816edb12b65 // indirect
 	k8s.io/kube-scheduler v0.23.10 // indirect
 	k8s.io/mount-utils v0.23.10 // indirect
-	k8s.io/utils v0.0.0-20211116205334-6203023598ed // indirect
+	k8s.io/utils v0.0.0-20211208161948-7d6a63dca704 // indirect
 	mvdan.cc/gofumpt v0.4.0 // indirect
 	mvdan.cc/interfacer v0.0.0-20180901003855-c20040233aed // indirect
 	mvdan.cc/lint v0.0.0-20170908181259-adc824a0674b // indirect

go.sum

@@ -268,8 +268,11 @@ github.com/dustin/go-humanize v1.0.0 h1:VSnTsYCnlFHaM2/igO1h6X3HA71jcobQuxemgkq4
 github.com/dustin/go-humanize v1.0.0/go.mod h1:HtrtbFcZ19U5GC7JDqmcUSB87Iq5E25KnS6fMYU6eOk=
 github.com/elazarl/goproxy v0.0.0-20180725130230-947c36da3153/go.mod h1:/Zj4wYkgs4iZTTu3o/KG3Itv/qCCa8VVMlb3i9OVuzc=
 github.com/emicklei/go-restful v0.0.0-20170410110728-ff4f55a20633/go.mod h1:otzb+WCGbkyDHkqmQmT5YD2WR4BBwUdeQoFo8l/7tVs=
-github.com/emicklei/go-restful v2.9.5+incompatible h1:spTtZBk5DYEvbxMVutUuTyh1Ao2r4iyvLdACqsl/Ljk=
 github.com/emicklei/go-restful v2.9.5+incompatible/go.mod h1:otzb+WCGbkyDHkqmQmT5YD2WR4BBwUdeQoFo8l/7tVs=
+github.com/emicklei/go-restful v2.15.0+incompatible h1:8KpYO/Xl/ZudZs5RNOEhWMBY4hmzlZhhRd9cu+jrZP4=
+github.com/emicklei/go-restful v2.15.0+incompatible/go.mod h1:otzb+WCGbkyDHkqmQmT5YD2WR4BBwUdeQoFo8l/7tVs=
+github.com/emicklei/go-restful-swagger12 v0.0.0-20201014110547-68ccff494617 h1:jri9taV4TK9oItoWJCofXJi21Dp/k25u32NnfphqLAY=
+github.com/emicklei/go-restful-swagger12 v0.0.0-20201014110547-68ccff494617/go.mod h1:qr0VowGBT4CS4Q8vFF8BSeKz34PuqKGxs/L0IAQA9DQ=
 github.com/envoyproxy/go-control-plane v0.9.0/go.mod h1:YTl/9mNaCwkRvm6d1a2C3ymFceY/DCBVvsKhRF0iEA4=
 github.com/envoyproxy/go-control-plane v0.9.1-0.20191026205805-5f8ba28d4473/go.mod h1:YTl/9mNaCwkRvm6d1a2C3ymFceY/DCBVvsKhRF0iEA4=
 github.com/envoyproxy/go-control-plane v0.9.4/go.mod h1:6rpuAdCZL397s3pYoYcLgu1mIlRU8Am5FuJP05cCM98=
@@ -341,11 +344,13 @@ github.com/go-openapi/jsonpointer v0.19.3/go.mod h1:Pl9vOtqEWErmShwVjC8pYs9cog34
 github.com/go-openapi/jsonpointer v0.19.5 h1:gZr+CIYByUqjcgeLXnQu2gHYQC9o73G2XUeOFYEICuY=
 github.com/go-openapi/jsonpointer v0.19.5/go.mod h1:Pl9vOtqEWErmShwVjC8pYs9cog34VGT37dQOVbmoatg=
 github.com/go-openapi/jsonreference v0.19.3/go.mod h1:rjx6GuL8TTa9VaixXglHmQmIL98+wF9xc8zWvFonSJ8=
-github.com/go-openapi/jsonreference v0.19.5 h1:1WJP/wi4OjB4iV8KVbH73rQaoialJrqv8gitZLxGLtM=
 github.com/go-openapi/jsonreference v0.19.5/go.mod h1:RdybgQwPxbL4UEjuAruzK1x3nE69AqPYEJeo/TWfEeg=
+github.com/go-openapi/jsonreference v0.19.6 h1:UBIxjkht+AWIgYzCDSv2GN+E/togfwXUJFRTWhl2Jjs=
+github.com/go-openapi/jsonreference v0.19.6/go.mod h1:diGHMEHg2IqXZGKxqyvWdfWU/aim5Dprw5bqpKkTvns=
 github.com/go-openapi/swag v0.19.5/go.mod h1:POnQmlKehdgb5mhVOsnJFsivZCEZ/vjK9gh66Z9tfKk=
-github.com/go-openapi/swag v0.19.14 h1:gm3vOOXfiuw5i9p5N9xJvfjvuofpyvLA9Wr6QfK5Fng=
 github.com/go-openapi/swag v0.19.14/go.mod h1:QYRuS/SOXUCsnplDa677K7+DxSOj6IPNl/eQntq43wQ=
+github.com/go-openapi/swag v0.19.15 h1:D2NRCBzS9/pEY3gP9Nl8aDqGUcPFrwG2p+CNFrLyrCM=
+github.com/go-openapi/swag v0.19.15/go.mod h1:QYRuS/SOXUCsnplDa677K7+DxSOj6IPNl/eQntq43wQ=
 github.com/go-ozzo/ozzo-validation v3.5.0+incompatible/go.mod h1:gsEKFIVnabGBt6mXmxK0MoFy+cZoTJY6mu5Ll3LVLBU=
 github.com/go-sourcemap/sourcemap v2.1.3+incompatible h1:W1iEw64niKVGogNgBN3ePyLFfuisuzeidWPMPWmECqU=
 github.com/go-sourcemap/sourcemap v2.1.3+incompatible/go.mod h1:F8jJfvm2KbVjc5NqelyYJmf/v5J0dwNLS2mL4sNA1Jg=
@@ -1193,6 +1198,7 @@ golang.org/x/net v0.0.0-20210119194325-5f4716e94777/go.mod h1:m0MpNAwzfU5UDzcl9v
 golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
 golang.org/x/net v0.0.0-20210316092652-d523dce5a7f4/go.mod h1:RBQZq4jEuRlivfhVLdyRGr576XBO4/greRjx4P4O3yc=
 golang.org/x/net v0.0.0-20210405180319-a5a99cb37ef4/go.mod h1:p54w0d4576C0XHj96bSt6lcn1PtDYWL6XObtHCRCNQM=
+golang.org/x/net v0.0.0-20210421230115-4e50805a0758/go.mod h1:72T/g9IO56b78aLF+1Kcs5dz7/ng1VjMUvfKvpfy+jM=
 golang.org/x/net v0.0.0-20210503060351-7fd8e65b6420/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
 golang.org/x/net v0.0.0-20210525063256-abc453219eb5/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
 golang.org/x/net v0.0.0-20210805182204-aaa1db679c0d/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
@@ -1311,6 +1317,7 @@ golang.org/x/sys v0.0.0-20210320140829-1e4c9ba3b0c4/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20210324051608-47abb6519492/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210330210617-4fbd30eecc44/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210403161142-5e06dd20ab57/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20210420072515-93ed5bcd2bfe/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210423082822-04245dca01da/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210423185535-09eb48e85fd7/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210426230700-d19ff857e887/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
@@ -1731,13 +1738,15 @@ k8s.io/gengo v0.0.0-20210813121822-485abfe95c7c/go.mod h1:FiNAH4ZV3gBg2Kwh89tzAE
 k8s.io/klog/v2 v2.0.0/go.mod h1:PBfzABfn139FHAV07az/IF9Wp1bkk3vpT2XSJ76fSDE=
 k8s.io/klog/v2 v2.2.0/go.mod h1:Od+F08eJP+W3HUb4pSrPpgp9DGU4GzlpG/TmITuYh/Y=
 k8s.io/klog/v2 v2.4.0/go.mod h1:Od+F08eJP+W3HUb4pSrPpgp9DGU4GzlpG/TmITuYh/Y=
-k8s.io/klog/v2 v2.30.0 h1:bUO6drIvCIsvZ/XFgfxoGFQU/a4Qkh0iAlvUR7vlHJw=
 k8s.io/klog/v2 v2.30.0/go.mod h1:y1WjHnz7Dj687irZUWR/WLkLc5N1YHtjLdmgWjndZn0=
+k8s.io/klog/v2 v2.40.1 h1:P4RRucWk/lFOlDdkAr3mc7iWFkgKrZY9qZMAgek06S4=
+k8s.io/klog/v2 v2.40.1/go.mod h1:y1WjHnz7Dj687irZUWR/WLkLc5N1YHtjLdmgWjndZn0=
 k8s.io/kube-aggregator v0.23.10/go.mod h1:DXNnJCsvvhv3tT60aSN3C1IER03PRT7BjXAs+cXg7Q8=
 k8s.io/kube-controller-manager v0.23.10/go.mod h1:KuydBU2blURmG1X/yPUOIaGnWul2d75zv+HKU/C4DGw=
 k8s.io/kube-openapi v0.0.0-20210421082810-95288971da7e/go.mod h1:vHXdDvt9+2spS2Rx9ql3I8tycm3H9FDfdUoIuKCefvw=
-k8s.io/kube-openapi v0.0.0-20211115234752-e816edb12b65 h1:E3J9oCLlaobFUqsjG9DfKbP2BmgwBL2p7pn0A3dG9W4=
 k8s.io/kube-openapi v0.0.0-20211115234752-e816edb12b65/go.mod h1:sX9MT8g7NVZM5lVL/j8QyCCJe8YSMW30QvGZWaCIDIk=
+k8s.io/kube-openapi v0.0.0-20220124234850-424119656bbf h1:M9XBsiMslw2lb2ZzglC0TOkBPK5NQi0/noUrdnoFwUg=
+k8s.io/kube-openapi v0.0.0-20220124234850-424119656bbf/go.mod h1:sX9MT8g7NVZM5lVL/j8QyCCJe8YSMW30QvGZWaCIDIk=
 k8s.io/kube-proxy v0.23.10/go.mod h1:56ImmMXi1L+6hmGkT7S7sqh20XaSXxyoLYY7bOMjcjk=
 k8s.io/kube-scheduler v0.23.10 h1:hXi+DNrNWpsbFaC0pHFKpkHONvlvnejnItyDb7VgejM=
 k8s.io/kube-scheduler v0.23.10/go.mod h1:+FJAaaQB82MtF44ragZI5FATXjpKItraE2NBsD8uxRU=
@@ -1746,6 +1755,7 @@ k8s.io/kubelet v0.23.10/go.mod h1:EXD0pzZM23imz3lQLGRvb99ub+Gv0a4PREuTcNL8BHQ=
 k8s.io/kubernetes v1.23.10 h1:mgs1AJoKaBd4umoS7Z5A9dbWHkhgrUfdQ2nJiUQWSNM=
 k8s.io/kubernetes v1.23.10/go.mod h1:IgVzsE4wzcjQ2olWQskgJX30Hx3fOODQp3Jqp6E/Vzw=
 k8s.io/legacy-cloud-providers v0.23.10/go.mod h1:xqVuI2i/9ZT3wpXrc8ndNgvkuPfWcDKtE9kzCoOtlDg=
+k8s.io/metrics v0.23.10 h1:KqRuN/Uxon7N8jWaUC9YtwwSMKdlGGz/YMpEVHQ1t/s=
 k8s.io/metrics v0.23.10/go.mod h1:nEnEo9l9Dk/vYJNi+aUXFLazzd61evhxYg1SY2ruhDQ=
 k8s.io/mount-utils v0.23.10 h1:nv2sRmNlrf4xx2LY41uYGHuwVwuWz4MWt6NSM/WDMeU=
 k8s.io/mount-utils v0.23.10/go.mod h1:OTN3LQPiOGMfx/SmVlsnySwsAmh4gYrDYLchlMHtf98=
@@ -1754,8 +1764,9 @@ k8s.io/sample-apiserver v0.23.10/go.mod h1:qL+UkPLDo9VOd2FfRlW2habqqffsepjXk+jdC
 k8s.io/system-validators v1.6.0/go.mod h1:bPldcLgkIUK22ALflnsXk8pvkTEndYdNuaHH6gRrl0Q=
 k8s.io/utils v0.0.0-20201110183641-67b214c5f920/go.mod h1:jPW/WVKK9YHAvNhRxK0md/EJ228hCsBRufyofKtW8HA=
 k8s.io/utils v0.0.0-20210802155522-efc7438f0176/go.mod h1:jPW/WVKK9YHAvNhRxK0md/EJ228hCsBRufyofKtW8HA=
-k8s.io/utils v0.0.0-20211116205334-6203023598ed h1:ck1fRPWPJWsMd8ZRFsWc6mh/zHp5fZ/shhbrgPUxDAE=
 k8s.io/utils v0.0.0-20211116205334-6203023598ed/go.mod h1:jPW/WVKK9YHAvNhRxK0md/EJ228hCsBRufyofKtW8HA=
+k8s.io/utils v0.0.0-20211208161948-7d6a63dca704 h1:ZKMMxTvduyf5WUtREOqg5LiXaN1KO/+0oOQPRFrClpo=
+k8s.io/utils v0.0.0-20211208161948-7d6a63dca704/go.mod h1:jPW/WVKK9YHAvNhRxK0md/EJ228hCsBRufyofKtW8HA=
 modernc.org/cc v1.0.0/go.mod h1:1Sk4//wdnYJiUIxnW8ddKpaOJCF37yAdqYnkxUpaYxw=
 modernc.org/golex v1.0.0/go.mod h1:b/QX9oBD/LhixY6NDh+IdGv17hgB+51fET1i2kPSmvk=
 modernc.org/mathutil v1.0.0/go.mod h1:wU0vUrJsVWBZ4P6e7xtFJEhFSNsfRLJ8H458uRjg03k=
@@ -1777,6 +1788,8 @@ sigs.k8s.io/apiserver-network-proxy/konnectivity-client v0.0.30 h1:dUk62HQ3ZFhD4
 sigs.k8s.io/apiserver-network-proxy/konnectivity-client v0.0.30/go.mod h1:fEO7lRTdivWO2qYVCVG7dEADOMo/MLDCVr8So2g88Uw=
 sigs.k8s.io/controller-runtime v0.11.1 h1:7YIHT2QnHJArj/dk9aUkYhfqfK5cIxPOX5gPECfdZLU=
 sigs.k8s.io/controller-runtime v0.11.1/go.mod h1:KKwLiTooNGu+JmLZGn9Sl3Gjmfj66eMbCQznLP5zcqA=
+sigs.k8s.io/custom-metrics-apiserver v1.23.0 h1:GQfmPQFnqQWCJ+HrSONkFNW4OPirx9AuzP8xbjQixmo=
+sigs.k8s.io/custom-metrics-apiserver v1.23.0/go.mod h1:fh9GeIlqMqo3xs7OUL7kUPdaCG/Pk3CmrtY4arf0eZw=
 sigs.k8s.io/json v0.0.0-20211020170558-c049b76a60c6 h1:fD1pz4yfdADVNfFmcP2aBEtudwUQ1AlLnRBALr33v3s=
 sigs.k8s.io/json v0.0.0-20211020170558-c049b76a60c6/go.mod h1:p4QtZmO4uMYipTQNzagwnNoseA6OxSUutVw05NhYDRs=
 sigs.k8s.io/kustomize/api v0.10.1 h1:KgU7hfYoscuqag84kxtzKdEC3mKMb99DPI3a0eaV1d0=
@@ -1785,6 +1798,8 @@ sigs.k8s.io/kustomize/cmd/config v0.10.2/go.mod h1:K2aW7nXJ0AaT+VA/eO0/dzFLxmpFc
 sigs.k8s.io/kustomize/kustomize/v4 v4.4.1/go.mod h1:qOKJMMz2mBP+vcS7vK+mNz4HBLjaQSWRY22EF6Tb7Io=
 sigs.k8s.io/kustomize/kyaml v0.13.0 h1:9c+ETyNfSrVhxvphs+K2dzT3dh5oVPPEqPOE/cUpScY=
 sigs.k8s.io/kustomize/kyaml v0.13.0/go.mod h1:FTJxEZ86ScK184NpGSAQcfEqee0nul8oLCK30D47m4E=
+sigs.k8s.io/metrics-server v0.6.1 h1:XooqhTZu+HltKmPQYkzIarTvAbNvJOVhNLCqsZrznsI=
+sigs.k8s.io/metrics-server v0.6.1/go.mod h1:n0EsNkwCRklMlcIq4z2MzokErhVzg+Njly0tlWnl3yQ=
 sigs.k8s.io/structured-merge-diff/v4 v4.0.2/go.mod h1:bJZC9H9iH24zzfZ/41RGcq60oK1F7G282QMXDPYydCw=
 sigs.k8s.io/structured-merge-diff/v4 v4.2.1 h1:bKCqE9GvQ5tiVHn5rfn1r+yao3aLQEaLzkkmAkf+A6Y=
 sigs.k8s.io/structured-merge-diff/v4 v4.2.1/go.mod h1:j/nl6xW8vLS49O8YvXW1ocPhZawJtm+Yrr7PPRQ0Vg4=

hack/fix-golang-lint-error.sh

@@ -0,0 +1,19 @@
+#!/usr/bin/env bash
+
+set -o errexit
+set -o nounset
+set -o pipefail
+
+ROOT_PATH=$(dirname "${BASH_SOURCE[0]}")/..
+source "${ROOT_PATH}/hack/lib/init.sh"
+
+go::setup_env
+
+echo "installing golangci-lint"
+go install github.com/golangci/golangci-lint/cmd/golangci-lint
+
+cd "${ROOT_PATH}"
+
+echo "running golangci-lint --fix"
+
+golangci-lint run --fix

manifests/example/adapter/hpa-using-obi.yaml

@@ -0,0 +1,17 @@
+apiVersion: autoscaling/v2beta1
+kind: HorizontalPodAutoscaler
+metadata:
+  name: hpa-using-obi-adapter
+spec:
+  scaleTargetRef:
+    apiVersion: apps/v1
+    kind: Deployment
+    name: mem-cost
+  minReplicas: 1
+  maxReplicas: 5
+  metrics:
+  - type: External
+    external:
+      metricName: prometheus-pod-mem
+      metricSelector: {}
+      targetValue: 202042048