Switch to ginkgo/gomega for tests

This switches over to ginkgo/gomega for tests, which makes writing
certain tests easier/more fluent in the future.

vendor/github.com/kubernetes-incubator/metrics-server/pkg/apiserver/generic/storage.go

@@ -0,0 +1,72 @@
+// Copyright 2018 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.
+
+package generic
+
+import (
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/apimachinery/pkg/runtime/serializer"
+	"k8s.io/apiserver/pkg/registry/rest"
+	genericapiserver "k8s.io/apiserver/pkg/server"
+	coreinf "k8s.io/client-go/informers/core/v1"
+	"k8s.io/metrics/pkg/apis/metrics"
+	"k8s.io/metrics/pkg/apis/metrics/install"
+	"k8s.io/metrics/pkg/apis/metrics/v1beta1"
+
+	"github.com/kubernetes-incubator/metrics-server/pkg/provider"
+	nodemetricsstorage "github.com/kubernetes-incubator/metrics-server/pkg/storage/nodemetrics"
+	podmetricsstorage "github.com/kubernetes-incubator/metrics-server/pkg/storage/podmetrics"
+)
+
+var (
+	// Scheme contains the types needed by the resource metrics API.
+	Scheme = runtime.NewScheme()
+	// Codecs is a codec factory for serving the resource metrics API.
+	Codecs = serializer.NewCodecFactory(Scheme)
+)
+
+func init() {
+	install.Install(Scheme)
+	metav1.AddToGroupVersion(Scheme, schema.GroupVersion{Version: "v1"})
+}
+
+// ProviderConfig holds the providers for node and pod metrics
+// for serving the resource metrics API.
+type ProviderConfig struct {
+	Node provider.NodeMetricsProvider
+	Pod  provider.PodMetricsProvider
+}
+
+// BuildStorage constructs APIGroupInfo the metrics.k8s.io API group using the given providers.
+func BuildStorage(providers *ProviderConfig, informers coreinf.Interface) genericapiserver.APIGroupInfo {
+	apiGroupInfo := genericapiserver.NewDefaultAPIGroupInfo(metrics.GroupName, Scheme, metav1.ParameterCodec, Codecs)
+
+	nodemetricsStorage := nodemetricsstorage.NewStorage(metrics.Resource("nodemetrics"), providers.Node, informers.Nodes().Lister())
+	podmetricsStorage := podmetricsstorage.NewStorage(metrics.Resource("podmetrics"), providers.Pod, informers.Pods().Lister())
+	metricsServerResources := map[string]rest.Storage{
+		"nodes": nodemetricsStorage,
+		"pods":  podmetricsStorage,
+	}
+	apiGroupInfo.VersionedResourcesStorageMap[v1beta1.SchemeGroupVersion.Version] = metricsServerResources
+
+	return apiGroupInfo
+}
+
+// InstallStorage builds the storage for the metrics.k8s.io API, and then installs it into the given API server.
+func InstallStorage(providers *ProviderConfig, informers coreinf.Interface, server *genericapiserver.GenericAPIServer) error {
+	info := BuildStorage(providers, informers)
+	return server.InstallAPIGroup(&info)
+}