Initial aggregated API server (#15)

Add initial aggregated API server (squashed from a bunch of commits).

Signed-off-by: Andrew Keesler <akeesler@vmware.com>
Signed-off-by: Aram Price <pricear@vmware.com>
Signed-off-by: Ryan Richard <richardry@vmware.com>

pkg/apiserver/apiserver.go

@@ -0,0 +1,132 @@
+/*
+Copyright 2020 VMware, Inc.
+SPDX-License-Identifier: Apache-2.0
+*/
+
+package apiserver
+
+import (
+	"fmt"
+
+	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"
+	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
+	"k8s.io/apiserver/pkg/authentication/authenticator"
+	"k8s.io/apiserver/pkg/registry/rest"
+	genericapiserver "k8s.io/apiserver/pkg/server"
+	"k8s.io/client-go/pkg/version"
+	"k8s.io/klog/v2"
+
+	placeholderapi "github.com/suzerain-io/placeholder-name-api/pkg/apis/placeholder"
+	placeholderv1alpha1 "github.com/suzerain-io/placeholder-name-api/pkg/apis/placeholder/v1alpha1"
+	"github.com/suzerain-io/placeholder-name/pkg/registry/loginrequest"
+)
+
+var (
+	//nolint: gochecknoglobals
+	scheme = runtime.NewScheme()
+	//nolint: gochecknoglobals
+	//nolint: golint
+	Codecs = serializer.NewCodecFactory(scheme)
+)
+
+//nolint: gochecknoinits
+func init() {
+	utilruntime.Must(placeholderv1alpha1.AddToScheme(scheme))
+	utilruntime.Must(placeholderapi.AddToScheme(scheme))
+
+	// add the options to empty v1
+	metav1.AddToGroupVersion(scheme, schema.GroupVersion{Version: "v1"})
+
+	unversioned := schema.GroupVersion{Group: "", Version: "v1"}
+	scheme.AddUnversionedTypes(unversioned,
+		&metav1.Status{},
+		&metav1.APIVersions{},
+		&metav1.APIGroupList{},
+		&metav1.APIGroup{},
+		&metav1.APIResourceList{},
+	)
+}
+
+type Config struct {
+	GenericConfig *genericapiserver.RecommendedConfig
+	ExtraConfig   ExtraConfig
+}
+
+type ExtraConfig struct {
+	Webhook authenticator.Token
+}
+
+type PlaceHolderServer struct {
+	GenericAPIServer *genericapiserver.GenericAPIServer
+}
+
+type completedConfig struct {
+	GenericConfig genericapiserver.CompletedConfig
+	ExtraConfig   *ExtraConfig
+}
+
+type CompletedConfig struct {
+	// Embed a private pointer that cannot be instantiated outside of this package.
+	*completedConfig
+}
+
+// Complete fills in any fields not set that are required to have valid data. It's mutating the receiver.
+func (c *Config) Complete() CompletedConfig {
+	completedCfg := completedConfig{
+		c.GenericConfig.Complete(),
+		&c.ExtraConfig,
+	}
+
+	versionInfo := version.Get()
+	completedCfg.GenericConfig.Version = &versionInfo
+
+	return CompletedConfig{completedConfig: &completedCfg}
+}
+
+// New returns a new instance of AdmissionServer from the given config.
+func (c completedConfig) New() (*PlaceHolderServer, error) {
+	genericServer, err := c.GenericConfig.New("place-holder-server", genericapiserver.NewEmptyDelegate()) // completion is done in Complete, no need for a second time
+	if err != nil {
+		return nil, fmt.Errorf("completion error: %w", err)
+	}
+
+	s := &PlaceHolderServer{
+		GenericAPIServer: genericServer,
+	}
+
+	gvr := placeholderv1alpha1.SchemeGroupVersion.WithResource("loginrequests")
+
+	apiGroupInfo := genericapiserver.APIGroupInfo{
+		PrioritizedVersions:          []schema.GroupVersion{gvr.GroupVersion()},
+		VersionedResourcesStorageMap: map[string]map[string]rest.Storage{},
+		OptionsExternalVersion:       &schema.GroupVersion{Version: "v1"},
+		Scheme:                       scheme,
+		ParameterCodec:               metav1.ParameterCodec,
+		NegotiatedSerializer:         Codecs,
+	}
+
+	loginRequestStorage := loginrequest.NewREST(c.ExtraConfig.Webhook)
+
+	v1alpha1Storage, ok := apiGroupInfo.VersionedResourcesStorageMap[gvr.Version]
+	if !ok {
+		v1alpha1Storage = map[string]rest.Storage{}
+	}
+	v1alpha1Storage[gvr.Resource] = loginRequestStorage
+	apiGroupInfo.VersionedResourcesStorageMap[gvr.Version] = v1alpha1Storage
+
+	if err := s.GenericAPIServer.InstallAPIGroup(&apiGroupInfo); err != nil {
+		return nil, fmt.Errorf("install API group error: %w", err)
+	}
+
+	s.GenericAPIServer.AddPostStartHookOrDie("place-holder-post-start-hook",
+		func(context genericapiserver.PostStartHookContext) error {
+			klog.InfoS("post start hook", "foo", "bar")
+			return nil
+		},
+	)
+
+	return s, nil
+}