aggregator: wire OpenAPI correctly into PrepareRun flow

cmd/kube-apiserver/app/server.go

@@ -153,11 +153,16 @@ func Run(completeOptions completedServerRunOptions, stopCh <-chan struct{}) erro
 		return err
 	}
 
-	return server.PrepareRun().Run(stopCh)
+	prepared, err := server.PrepareRun()
+	if err != nil {
+		return err
+	}
+
+	return prepared.Run(stopCh)
 }
 
 // CreateServerChain creates the apiservers connected via delegation.
-func CreateServerChain(completedOptions completedServerRunOptions, stopCh <-chan struct{}) (*genericapiserver.GenericAPIServer, error) {
+func CreateServerChain(completedOptions completedServerRunOptions, stopCh <-chan struct{}) (*aggregatorapiserver.APIAggregator, error) {
 	nodeTunneler, proxyTransport, err := CreateNodeDialer(completedOptions)
 	if err != nil {
 		return nil, err
@@ -202,7 +207,7 @@ func CreateServerChain(completedOptions completedServerRunOptions, stopCh <-chan
 		}
 	}
 
-	return aggregatorServer.GenericAPIServer, nil
+	return aggregatorServer, nil
 }
 
 // CreateKubeAPIServer creates and wires a workable kube-apiserver

cmd/kube-apiserver/app/testing/testserver.go

@@ -147,25 +147,30 @@ func StartTestServer(t Logger, instanceOptions *TestServerInstanceOptions, custo
 	t.Logf("runtime-config=%v", completedOptions.APIEnablement.RuntimeConfig)
 	t.Logf("Starting kube-apiserver on port %d...", s.SecureServing.BindPort)
 	server, err := app.CreateServerChain(completedOptions, stopCh)
-
-	if instanceOptions.InjectedHealthzChecker != nil {
-		t.Logf("Adding health check with delay %v %v", s.GenericServerRunOptions.MaxStartupSequenceDuration, instanceOptions.InjectedHealthzChecker.Name())
-		server.AddDelayedHealthzChecks(s.GenericServerRunOptions.MaxStartupSequenceDuration, instanceOptions.InjectedHealthzChecker)
-	}
-
 	if err != nil {
 		return result, fmt.Errorf("failed to create server chain: %v", err)
 	}
+
+	if instanceOptions.InjectedHealthzChecker != nil {
+		t.Logf("Adding health check with delay %v %v", s.GenericServerRunOptions.MaxStartupSequenceDuration, instanceOptions.InjectedHealthzChecker.Name())
+		if err := server.GenericAPIServer.AddDelayedHealthzChecks(s.GenericServerRunOptions.MaxStartupSequenceDuration, instanceOptions.InjectedHealthzChecker); err != nil {
+			return result, err
+		}
+	}
+
 	errCh := make(chan error)
 	go func(stopCh <-chan struct{}) {
-		if err := server.PrepareRun().Run(stopCh); err != nil {
+		prepared, err := server.PrepareRun()
+		if err != nil {
+			errCh <- err
+		} else if err := prepared.Run(stopCh); err != nil {
 			errCh <- err
 		}
 	}(stopCh)
 
 	t.Logf("Waiting for /healthz to be ok...")
 
-	client, err := kubernetes.NewForConfig(server.LoopbackClientConfig)
+	client, err := kubernetes.NewForConfig(server.GenericAPIServer.LoopbackClientConfig)
 	if err != nil {
 		return result, fmt.Errorf("failed to create a client: %v", err)
 	}
@@ -211,7 +216,7 @@ func StartTestServer(t Logger, instanceOptions *TestServerInstanceOptions, custo
 	}
 
 	// from here the caller must call tearDown
-	result.ClientConfig = server.LoopbackClientConfig
+	result.ClientConfig = server.GenericAPIServer.LoopbackClientConfig
 	result.ClientConfig.QPS = 1000
 	result.ClientConfig.Burst = 10000
 	result.ServerOpts = s

hack/.golint_failures

@@ -535,6 +535,7 @@ staging/src/k8s.io/component-base/featuregate
 staging/src/k8s.io/cri-api/pkg/apis/testing
 staging/src/k8s.io/kube-aggregator/pkg/apis/apiregistration/v1
 staging/src/k8s.io/kube-aggregator/pkg/apis/apiregistration/v1beta1
+staging/src/k8s.io/kube-aggregator/pkg/apiserver
 staging/src/k8s.io/kube-aggregator/pkg/controllers/autoregister
 staging/src/k8s.io/kube-proxy/config/v1alpha1
 staging/src/k8s.io/kubectl/pkg/util/templates

staging/src/k8s.io/kube-aggregator/pkg/apiserver/BUILD

@@ -83,6 +83,7 @@ go_library(
         "//staging/src/k8s.io/kube-aggregator/pkg/controllers/status:go_default_library",
         "//staging/src/k8s.io/kube-aggregator/pkg/registry/apiservice/rest:go_default_library",
         "//vendor/k8s.io/klog:go_default_library",
+        "//vendor/k8s.io/kube-openapi/pkg/common:go_default_library",
     ],
 )
 

staging/src/k8s.io/kube-aggregator/pkg/apiserver/apiserver.go

@@ -26,9 +26,10 @@ import (
 	genericapiserver "k8s.io/apiserver/pkg/server"
 	serverstorage "k8s.io/apiserver/pkg/server/storage"
 	"k8s.io/client-go/pkg/version"
+	openapicommon "k8s.io/kube-openapi/pkg/common"
 
 	"k8s.io/kube-aggregator/pkg/apis/apiregistration"
-	"k8s.io/kube-aggregator/pkg/apis/apiregistration/v1"
+	v1 "k8s.io/kube-aggregator/pkg/apis/apiregistration/v1"
 	"k8s.io/kube-aggregator/pkg/apis/apiregistration/v1beta1"
 	aggregatorscheme "k8s.io/kube-aggregator/pkg/apiserver/scheme"
 	"k8s.io/kube-aggregator/pkg/client/clientset_generated/internalclientset"
@@ -89,6 +90,16 @@ type CompletedConfig struct {
 	*completedConfig
 }
 
+type runnable interface {
+	Run(stopCh <-chan struct{}) error
+}
+
+// preparedGenericAPIServer is a private wrapper that enforces a call of PrepareRun() before Run can be invoked.
+type preparedAPIAggregator struct {
+	*APIAggregator
+	runnable runnable
+}
+
 // APIAggregator contains state for a Kubernetes cluster master/api server.
 type APIAggregator struct {
 	GenericAPIServer *genericapiserver.GenericAPIServer
@@ -116,6 +127,10 @@ type APIAggregator struct {
 	// Information needed to determine routing for the aggregator
 	serviceResolver ServiceResolver
 
+	// Enable swagger and/or OpenAPI if these configs are non-nil.
+	openAPIConfig *openapicommon.Config
+
+	// openAPIAggregationController downloads and merges OpenAPI specs.
 	openAPIAggregationController *openapicontroller.AggregationController
 }
 
@@ -167,6 +182,7 @@ func (c completedConfig) NewWithDelegate(delegationTarget genericapiserver.Deleg
 		lister:                   informerFactory.Apiregistration().InternalVersion().APIServices().Lister(),
 		APIRegistrationInformers: informerFactory,
 		serviceResolver:          c.ExtraConfig.ServiceResolver,
+		openAPIConfig:            openAPIConfig,
 	}
 
 	apiGroupInfo := apiservicerest.NewRESTStorage(c.GenericConfig.MergedResourceConfig, c.GenericConfig.RESTOptionsGetter)
@@ -211,26 +227,42 @@ func (c completedConfig) NewWithDelegate(delegationTarget genericapiserver.Deleg
 		return nil
 	})
 
-	if openAPIConfig != nil {
+	return s, nil
-		specDownloader := openapiaggregator.NewDownloader()
+}
-		openAPIAggregator, err := openapiaggregator.BuildAndRegisterAggregator(
-			&specDownloader,
-			delegationTarget,
-			s.GenericAPIServer.Handler.GoRestfulContainer.RegisteredWebServices(),
-			openAPIConfig,
-			s.GenericAPIServer.Handler.NonGoRestfulMux)
-		if err != nil {
-			return nil, err
-		}
-		s.openAPIAggregationController = openapicontroller.NewAggregationController(&specDownloader, openAPIAggregator)
 
+// PrepareRun prepares the aggregator to run, by setting up the OpenAPI spec and calling
+// the generic PrepareRun.
+func (s *APIAggregator) PrepareRun() (preparedAPIAggregator, error) {
+	// add post start hook before generic PrepareRun in order to be before /healthz installation
+	if s.openAPIConfig != nil {
 		s.GenericAPIServer.AddPostStartHookOrDie("apiservice-openapi-controller", func(context genericapiserver.PostStartHookContext) error {
 			go s.openAPIAggregationController.Run(context.StopCh)
 			return nil
 		})
 	}
 
-	return s, nil
+	prepared := s.GenericAPIServer.PrepareRun()
+
+	// delay OpenAPI setup until the delegate had a chance to setup their OpenAPI handlers
+	if s.openAPIConfig != nil {
+		specDownloader := openapiaggregator.NewDownloader()
+		openAPIAggregator, err := openapiaggregator.BuildAndRegisterAggregator(
+			&specDownloader,
+			s.GenericAPIServer.NextDelegate(),
+			s.GenericAPIServer.Handler.GoRestfulContainer.RegisteredWebServices(),
+			s.openAPIConfig,
+			s.GenericAPIServer.Handler.NonGoRestfulMux)
+		if err != nil {
+			return preparedAPIAggregator{}, err
+		}
+		s.openAPIAggregationController = openapicontroller.NewAggregationController(&specDownloader, openAPIAggregator)
+	}
+
+	return preparedAPIAggregator{APIAggregator: s, runnable: prepared}, nil
+}
+
+func (s preparedAPIAggregator) Run(stopCh <-chan struct{}) error {
+	return s.runnable.Run(stopCh)
 }
 
 // AddAPIService adds an API service.  It is not thread-safe, so only call it on one thread at a time please.

test/integration/etcd/server.go

@@ -117,7 +117,7 @@ func StartRealMasterOrDie(t *testing.T, configFuncs ...func(*options.ServerRunOp
 		t.Fatal(err)
 	}
 
-	kubeClientConfig := restclient.CopyConfig(kubeAPIServer.LoopbackClientConfig)
+	kubeClientConfig := restclient.CopyConfig(kubeAPIServer.GenericAPIServer.LoopbackClientConfig)
 
 	// we make lots of requests, don't be slow
 	kubeClientConfig.QPS = 99999
@@ -133,7 +133,11 @@ func StartRealMasterOrDie(t *testing.T, configFuncs ...func(*options.ServerRunOp
 			}
 		}()
 
-		if err := kubeAPIServer.PrepareRun().Run(stopCh); err != nil {
+		prepared, err := kubeAPIServer.PrepareRun()
+		if err != nil {
+			t.Fatal(err)
+		}
+		if err := prepared.Run(stopCh); err != nil {
 			t.Fatal(err)
 		}
 	}()