Add openapi spec

.github/workflows/pr-validation.yml

@@ -23,6 +23,9 @@ jobs:
           restore-keys: |
             ${{ runner.os }}-go-
 
+      - name: Go modules sync
+        run: go mod tidy
+
       - name: Verify Generated clientset is up to date
         run: make clientset-verify
 

.golangci.yml

@@ -60,7 +60,10 @@ issues:
     - path: _finalizer.go
       linters:
         - interfacer
-
+    # Excluding the stackdriver_client scaler until it is fixed: https://github.com/kedacore/keda/pull/1512#issuecomment-763454243
+    - path: pkg/scalers/stackdriver_client.go
+      linters:
+        - staticcheck
     # https://github.com/go-critic/go-critic/issues/926
     - linters:
         - gocritic

CHANGELOG.md

@@ -39,6 +39,7 @@
 - Improve performance when fetching current scaling information on Deployments ([#1458](https://github.com/kedacore/keda/pull/1458))
 - Improve error reporting in prometheus scaler ([#1497](https://github.com/kedacore/keda/pull/1497))
 - Check that metricNames are unique in ScaledObject ([#1390](https://github.com/kedacore/keda/pull/1390))
+- Serve OpenAPI spec from KEDA Metrics Apiserver ([#1512](https://github.com/kedacore/keda/pull/1512))
 
 ### Breaking Changes
 

Makefile

@@ -173,9 +173,20 @@ manifests: controller-gen
 
 # Generate code (API)
 .PHONY: generate
-generate: controller-gen
+generate: controller-gen adapter/generated/openapi/zz_generated.openapi.go
 	$(CONTROLLER_GEN) object:headerFile="hack/boilerplate.go.txt" paths="./..."
 
+adapter/generated/openapi/zz_generated.openapi.go: go.mod go.sum
+	@OPENAPI_PATH=`go list -mod=readonly -m -f '{{.Dir}}' k8s.io/kube-openapi`; \
+	go run $${OPENAPI_PATH}/cmd/openapi-gen/openapi-gen.go --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 \
+	    --build-tag autogenerated \
+	    -h ./hack/boilerplate.go.txt \
+	    -p ./adapter/generated/openapi \
+	    -O zz_generated.openapi \
+	    -o ./ \
+	    -r /dev/null
+
 # find or download controller-gen
 # download controller-gen if necessary
 .PHONY: controller-gen

adapter/main.go

@@ -10,15 +10,18 @@ import (
 
 	appsv1 "k8s.io/api/apps/v1"
 	"k8s.io/apimachinery/pkg/util/wait"
+	openapinamer "k8s.io/apiserver/pkg/endpoints/openapi"
+	genericapiserver "k8s.io/apiserver/pkg/server"
 	"k8s.io/client-go/kubernetes/scheme"
 	"k8s.io/klog"
 	"k8s.io/klog/klogr"
 	"sigs.k8s.io/controller-runtime/pkg/client"
 	"sigs.k8s.io/controller-runtime/pkg/client/config"
 
-	basecmd "github.com/kubernetes-incubator/custom-metrics-apiserver/pkg/cmd"
-	"github.com/kubernetes-incubator/custom-metrics-apiserver/pkg/provider"
+	basecmd "github.com/kubernetes-sigs/custom-metrics-apiserver/pkg/cmd"
+	"github.com/kubernetes-sigs/custom-metrics-apiserver/pkg/provider"
 
+	generatedopenapi "github.com/kedacore/keda/v2/adapter/generated/openapi"
 	kedav1alpha1 "github.com/kedacore/keda/v2/api/v1alpha1"
 	prommetrics "github.com/kedacore/keda/v2/pkg/metrics"
 	kedaprovider "github.com/kedacore/keda/v2/pkg/provider"
@@ -111,6 +114,11 @@ func main() {
 	printVersion()
 
 	cmd := &Adapter{}
+
+	cmd.OpenAPIConfig = genericapiserver.DefaultOpenAPIConfig(generatedopenapi.GetOpenAPIDefinitions, openapinamer.NewDefinitionNamer(scheme.Scheme))
+	cmd.OpenAPIConfig.Info.Title = "keda-adapter"
+	cmd.OpenAPIConfig.Info.Version = "1.0.0"
+
 	cmd.Flags().StringVar(&cmd.Message, "msg", "starting adapter...", "startup message")
 	cmd.Flags().AddGoFlagSet(flag.CommandLine) // make sure we get the klog flags
 	cmd.Flags().IntVar(&prometheusMetricsPort, "metrics-port", 9022, "Set the port to expose prometheus metrics")

go.mod

@@ -15,7 +15,9 @@ require (
 	github.com/Huawei/gophercloud v1.0.21
 	github.com/Shopify/sarama v1.27.2
 	github.com/aws/aws-sdk-go v1.36.19
-	github.com/go-logr/logr v0.1.0
+	github.com/go-logr/logr v0.3.0
+	github.com/go-logr/zapr v0.3.0 // indirect
+	github.com/go-openapi/spec v0.20.0
 	github.com/go-redis/redis v6.15.9+incompatible
 	github.com/go-sql-driver/mysql v1.5.0
 	github.com/golang/mock v1.4.4
@@ -24,7 +26,7 @@ require (
 	github.com/hashicorp/vault/api v1.0.4
 	github.com/imdario/mergo v0.3.11
 	github.com/influxdata/influxdb-client-go/v2 v2.2.1
-	github.com/kubernetes-incubator/custom-metrics-apiserver v0.0.0-20200618121405-54026617ec44
+	github.com/kubernetes-sigs/custom-metrics-apiserver v0.0.0-20201216091021-1b9fa998bbaa
 	github.com/lib/pq v1.9.0
 	github.com/mitchellh/hashstructure v1.1.0
 	github.com/onsi/ginkgo v1.14.2
@@ -39,31 +41,23 @@ require (
 	go.mongodb.org/mongo-driver v1.1.2
 	golang.org/x/crypto v0.0.0-20201016220609-9e8e0b390897 // indirect
 	google.golang.org/api v0.36.0
-	google.golang.org/genproto v0.0.0-20200904004341-0bd0a958aa1d
+	google.golang.org/genproto v0.0.0-20201203001206-6486ece9c497
 	google.golang.org/grpc v1.34.0
-	k8s.io/api v0.18.8
-	k8s.io/apimachinery v0.18.8
-	k8s.io/client-go v12.0.0+incompatible
-	k8s.io/code-generator v0.18.8
+	k8s.io/api v0.20.2
+	k8s.io/apimachinery v0.20.2
+	k8s.io/apiserver v0.20.2
+	k8s.io/client-go v11.0.1-0.20190805182717-6502b5e7b1b5+incompatible
+	k8s.io/code-generator v0.20.0
 	k8s.io/klog v1.0.0
-	k8s.io/metrics v0.18.8
+	k8s.io/kube-openapi v0.0.0-20201113171705-d219536bb9fd
+	k8s.io/metrics v0.20.0
 	knative.dev/pkg v0.0.0-20201019114258-95e9532f0457
 	sigs.k8s.io/controller-runtime v0.6.4
 )
 
-replace (
-	k8s.io/apiserver => k8s.io/apiserver v0.18.8 // Required by kubernetes-incubator/custom-metrics-apiserver
-	k8s.io/client-go => k8s.io/client-go v0.18.8
-)
-
-// Required to resolve go/grpc issues
-// (grpc version needed by k8s.io/apiserver vs kubernetes-incubator/custom-metrics-apiserver)
-replace (
-	cloud.google.com/go => cloud.google.com/go v0.48.0
-	google.golang.org/api => google.golang.org/api v0.15.1
-	google.golang.org/genproto => google.golang.org/genproto v0.0.0-20191002211648-c459b9ce5143
-	google.golang.org/grpc => google.golang.org/grpc v1.26.0
-)
+replace k8s.io/client-go => k8s.io/client-go v0.20.2
 
-// Required for k8s.io/apiserver, using k8s.io/kube-openapi branch release-1.18
-replace k8s.io/kube-openapi => k8s.io/kube-openapi v0.0.0-20200410145947-61e04a5be9a6
+// adapter uses k8s.io/apiserver/pkg/server, which indirectly uses go.etcd.io/etcd/proxy/grpcproxy.
+// etcd is not compatible with newer grpc version, see here https://github.com/etcd-io/etcd/issues/12124
+// so until that is fixed, we will pin the grpc version to v1.29.1
+replace google.golang.org/grpc => google.golang.org/grpc v1.29.1