add prioritization for aggregation

Author: deads2k

api/protobuf-spec/k8s_io_kubernetes_pkg_api_v1.proto

@@ -25,6 +25,8 @@ import (
 	"net/http"
 	"strings"
 
+	"github.com/golang/glog"
+
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/labels"
 	"k8s.io/apimachinery/pkg/runtime/schema"
@@ -123,16 +125,74 @@ func createAggregatorServer(aggregatorConfig *aggregatorapiserver.Config, delega
 }
 
 func makeAPIService(gv schema.GroupVersion) *apiregistration.APIService {
+	apiServicePriority, ok := apiVersionPriorities[gv]
+	if !ok {
+		// if we aren't found, then we shouldn't register ourselves because it could result in a CRD group version
+		// being permanently stuck in the APIServices list.
+		glog.Infof("Skipping APIService creation for %v", gv)
+		return nil
+	}
 	return &apiregistration.APIService{
 		ObjectMeta: metav1.ObjectMeta{Name: gv.Version + "." + gv.Group},
 		Spec: apiregistration.APIServiceSpec{
-			Group:    gv.Group,
-			Version:  gv.Version,
-			Priority: 100,
+			Group:                gv.Group,
+			Version:              gv.Version,
+			GroupPriorityMinimum: apiServicePriority.group,
+			VersionPriority:      apiServicePriority.version,
 		},
 	}
 }
 
+type priority struct {
+	group   int32
+	version int32
+}
+
+// The proper way to resolve this letting the aggregator know the desired group and version-within-group order of the underlying servers
+// is to refactor the genericapiserver.DelegationTarget to include a list of priorities based on which APIs were installed.
+// This requires the APIGroupInfo struct to evolve and include the concept of priorities and to avoid mistakes, the core storage map there needs to be updated.
+// That ripples out every bit as far as you'd expect, so for 1.7 we'll include the list here instead of being built up during storage.
+var apiVersionPriorities = map[schema.GroupVersion]priority{
+	{Group: "", Version: "v1"}: {group: 18000, version: 1},
+	// extensions is above the rest for CLI compatibility, though the level of unqalified resource compatibility we
+	// can reasonably expect seems questionable.
+	{Group: "extensions", Version: "v1beta1"}: {group: 17900, version: 1},
+	// to my knowledge, nothing below here collides
+	{Group: "apps", Version: "v1beta1"}:                       {group: 17800, version: 1},
+	{Group: "authentication.k8s.io", Version: "v1"}:           {group: 17700, version: 15},
+	{Group: "authentication.k8s.io", Version: "v1beta1"}:      {group: 17700, version: 9},
+	{Group: "authorization.k8s.io", Version: "v1"}:            {group: 17600, version: 15},
+	{Group: "authorization.k8s.io", Version: "v1beta1"}:       {group: 17600, version: 9},
+	{Group: "autoscaling", Version: "v1"}:                     {group: 17500, version: 15},
+	{Group: "autoscaling", Version: "v2alpha1"}:               {group: 17500, version: 9},
+	{Group: "batch", Version: "v1"}:                           {group: 17400, version: 15},
+	{Group: "batch", Version: "v2alpha1"}:                     {group: 17400, version: 9},
+	{Group: "certificates.k8s.io", Version: "v1beta1"}:        {group: 17300, version: 9},
+	{Group: "networking.k8s.io", Version: "v1"}:               {group: 17200, version: 15},
+	{Group: "policy", Version: "v1beta1"}:                     {group: 17100, version: 9},
+	{Group: "rbac.authorization.k8s.io", Version: "v1beta1"}:  {group: 17000, version: 12},
+	{Group: "rbac.authorization.k8s.io", Version: "v1alpha1"}: {group: 17000, version: 9},
+	{Group: "settings.k8s.io", Version: "v1alpha1"}:           {group: 16900, version: 9},
+	{Group: "storage.k8s.io", Version: "v1"}:                  {group: 16800, version: 15},
+	{Group: "storage.k8s.io", Version: "v1beta1"}:             {group: 16800, version: 9},
+	{Group: "apiextensions.k8s.io", Version: "v1beta1"}:       {group: 16700, version: 9},
+
+	// arbitrarily starting openshift around 10000.
+	// bump authorization above RBAC
+	{Group: "authorization.openshift.io", Version: "v1"}: {group: 17050, version: 15},
+	{Group: "build.openshift.io", Version: "v1"}:         {group: 9900, version: 15},
+	{Group: "apps.openshift.io", Version: "v1"}:          {group: 9900, version: 15},
+	{Group: "image.openshift.io", Version: "v1"}:         {group: 9900, version: 15},
+	{Group: "oauth.openshift.io", Version: "v1"}:         {group: 9900, version: 15},
+	{Group: "project.openshift.io", Version: "v1"}:       {group: 9900, version: 15},
+	{Group: "quota.openshift.io", Version: "v1"}:         {group: 9900, version: 15},
+	{Group: "route.openshift.io", Version: "v1"}:         {group: 9900, version: 15},
+	{Group: "network.openshift.io", Version: "v1"}:       {group: 9900, version: 15},
+	{Group: "security.openshift.io", Version: "v1"}:      {group: 9900, version: 15},
+	{Group: "template.openshift.io", Version: "v1"}:      {group: 9900, version: 15},
+	{Group: "user.openshift.io", Version: "v1"}:          {group: 9900, version: 15},
+}
+
 func apiServicesToRegister(delegateAPIServer genericapiserver.DelegationTarget, registration autoregister.AutoAPIServiceRegistration) []*apiregistration.APIService {
 	apiServices := []*apiregistration.APIService{}
 
@@ -154,14 +214,9 @@ func apiServicesToRegister(delegateAPIServer genericapiserver.DelegationTarget,
 		}
 
 		apiService := makeAPIService(schema.GroupVersion{Group: tokens[2], Version: tokens[3]})
-
-		// TODO this is probably an indication that we need explicit and precise control over the discovery chain
-		// but for now its a special case
-		// apps has to come last for compatibility with 1.5 kubectl clients
-		if apiService.Spec.Group == "apps" {
-			apiService.Spec.Priority = 110
+		if apiService == nil {
+			continue
 		}
-
 		registration.AddAPIServiceToSync(apiService)
 		apiServices = append(apiServices, apiService)
 	}