APIServer: Move shared code to a utility/helper function (#80261)

pkg/services/grafana-apiserver/common.go

@@ -25,7 +25,7 @@ type APIGroupBuilder interface {
 	// Build the group+version behavior
 	GetAPIGroupInfo(
 		scheme *runtime.Scheme,
-		codecs serializer.CodecFactory, // pointer?
+		codecs serializer.CodecFactory,
 		optsGetter generic.RESTOptionsGetter,
 	) (*genericapiserver.APIGroupInfo, error)
 

pkg/services/grafana-apiserver/helper.go

@@ -0,0 +1,89 @@
+package grafanaapiserver
+
+import (
+	"fmt"
+	"net/http"
+	goruntime "runtime"
+	"strings"
+	"time"
+
+	"k8s.io/apimachinery/pkg/version"
+	openapinamer "k8s.io/apiserver/pkg/endpoints/openapi"
+	"k8s.io/apiserver/pkg/registry/generic"
+	genericapiserver "k8s.io/apiserver/pkg/server"
+	"k8s.io/apiserver/pkg/util/openapi"
+	"k8s.io/client-go/kubernetes/scheme"
+
+	"github.com/grafana/grafana/pkg/setting"
+)
+
+func SetupConfig(serverConfig *genericapiserver.RecommendedConfig, builders []APIGroupBuilder) error {
+	defsGetter := GetOpenAPIDefinitions(builders)
+	serverConfig.OpenAPIConfig = genericapiserver.DefaultOpenAPIConfig(
+		openapi.GetOpenAPIDefinitionsWithoutDisabledFeatures(defsGetter),
+		openapinamer.NewDefinitionNamer(Scheme, scheme.Scheme))
+
+	serverConfig.OpenAPIV3Config = genericapiserver.DefaultOpenAPIV3Config(
+		openapi.GetOpenAPIDefinitionsWithoutDisabledFeatures(defsGetter),
+		openapinamer.NewDefinitionNamer(Scheme, scheme.Scheme))
+
+	// Add the custom routes to service discovery
+	serverConfig.OpenAPIV3Config.PostProcessSpec = getOpenAPIPostProcessor(builders)
+
+	// Set the swagger build versions
+	serverConfig.OpenAPIConfig.Info.Version = setting.BuildVersion
+	serverConfig.OpenAPIV3Config.Info.Version = setting.BuildVersion
+
+	serverConfig.SkipOpenAPIInstallation = false
+	serverConfig.BuildHandlerChainFunc = func(delegateHandler http.Handler, c *genericapiserver.Config) http.Handler {
+		// Call DefaultBuildHandlerChain on the main entrypoint http.Handler
+		// See https://github.com/kubernetes/apiserver/blob/v0.28.0/pkg/server/config.go#L906
+		// DefaultBuildHandlerChain provides many things, notably CORS, HSTS, cache-control, authz and latency tracking
+		requestHandler, err := getAPIHandler(
+			delegateHandler,
+			c.LoopbackClientConfig,
+			builders)
+		if err != nil {
+			panic(fmt.Sprintf("could not build handler chain func: %s", err.Error()))
+		}
+		return genericapiserver.DefaultBuildHandlerChain(requestHandler, c)
+	}
+
+	k8sVersion, err := getK8sApiserverVersion()
+	if err != nil {
+		return err
+	}
+	before, after, _ := strings.Cut(setting.BuildVersion, ".")
+	serverConfig.Version = &version.Info{
+		Major:        before,
+		Minor:        after,
+		GoVersion:    goruntime.Version(),
+		Platform:     fmt.Sprintf("%s/%s", goruntime.GOOS, goruntime.GOARCH),
+		Compiler:     goruntime.Compiler,
+		GitTreeState: setting.BuildBranch,
+		GitCommit:    setting.BuildCommit,
+		BuildDate:    time.Unix(setting.BuildStamp, 0).UTC().Format(time.DateTime),
+		GitVersion:   k8sVersion,
+	}
+	return nil
+}
+
+func InstallAPIs(server *genericapiserver.GenericAPIServer,
+	optsGetter generic.RESTOptionsGetter,
+	builders []APIGroupBuilder,
+) error {
+	for _, b := range builders {
+		g, err := b.GetAPIGroupInfo(Scheme, Codecs, optsGetter)
+		if err != nil {
+			return err
+		}
+		if g == nil || len(g.PrioritizedVersions) < 1 {
+			continue
+		}
+		err = server.InstallAPIGroup(g)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}

pkg/services/grafana-apiserver/request_handler.go

@@ -16,7 +16,7 @@ type requestHandler struct {
 	router *mux.Router
 }
 
-func GetAPIHandler(delegateHandler http.Handler, restConfig *restclient.Config, builders []APIGroupBuilder) (http.Handler, error) {
+func getAPIHandler(delegateHandler http.Handler, restConfig *restclient.Config, builders []APIGroupBuilder) (http.Handler, error) {
 	useful := false // only true if any routes exist anywhere
 	router := mux.NewRouter()
 
@@ -120,7 +120,7 @@ func (h *methodNotAllowedHandler) ServeHTTP(w http.ResponseWriter, req *http.Req
 // Modify the the OpenAPI spec to include the additional routes.
 // Currently this requires: https://github.com/kubernetes/kube-openapi/pull/420
 // In future k8s release, the hook will use Config3 rather than the same hook for both v2 and v3
-func GetOpenAPIPostProcessor(builders []APIGroupBuilder) func(*spec3.OpenAPI) (*spec3.OpenAPI, error) {
+func getOpenAPIPostProcessor(builders []APIGroupBuilder) func(*spec3.OpenAPI) (*spec3.OpenAPI, error) {
 	return func(s *spec3.OpenAPI) (*spec3.OpenAPI, error) {
 		if s.Paths == nil {
 			return s, nil

pkg/services/grafana-apiserver/service.go

@@ -6,11 +6,9 @@ import (
 	"net/http"
 	"net/http/httptest"
 	"path"
-	goruntime "runtime"
 	"runtime/debug"
 	"strconv"
 	"strings"
-	"time"
 
 	"github.com/go-logr/logr"
 	"github.com/grafana/dskit/services"
@@ -21,13 +19,9 @@ import (
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/runtime/schema"
 	"k8s.io/apimachinery/pkg/runtime/serializer"
-	"k8s.io/apimachinery/pkg/version"
-	openapinamer "k8s.io/apiserver/pkg/endpoints/openapi"
 	"k8s.io/apiserver/pkg/endpoints/responsewriter"
 	genericapiserver "k8s.io/apiserver/pkg/server"
 	"k8s.io/apiserver/pkg/server/options"
-	"k8s.io/apiserver/pkg/util/openapi"
-	"k8s.io/client-go/kubernetes/scheme"
 	clientrest "k8s.io/client-go/rest"
 	"k8s.io/client-go/tools/clientcmd"
 	"k8s.io/component-base/logs"
@@ -325,53 +319,10 @@ func (s *service) start(ctx context.Context) error {
 	serverConfig.TracerProvider = s.tracing.GetTracerProvider()
 
 	// Add OpenAPI specs for each group+version
-	defsGetter := GetOpenAPIDefinitions(builders)
-	serverConfig.OpenAPIConfig = genericapiserver.DefaultOpenAPIConfig(
-		openapi.GetOpenAPIDefinitionsWithoutDisabledFeatures(defsGetter),
-		openapinamer.NewDefinitionNamer(Scheme, scheme.Scheme))
-
-	serverConfig.OpenAPIV3Config = genericapiserver.DefaultOpenAPIV3Config(
-		openapi.GetOpenAPIDefinitionsWithoutDisabledFeatures(defsGetter),
-		openapinamer.NewDefinitionNamer(Scheme, scheme.Scheme))
-
-	// Add the custom routes to service discovery
-	serverConfig.OpenAPIV3Config.PostProcessSpec = GetOpenAPIPostProcessor(builders)
-
-	// Set the swagger build versions
-	serverConfig.OpenAPIConfig.Info.Version = setting.BuildVersion
-	serverConfig.OpenAPIV3Config.Info.Version = setting.BuildVersion
-
-	serverConfig.SkipOpenAPIInstallation = false
-	serverConfig.BuildHandlerChainFunc = func(delegateHandler http.Handler, c *genericapiserver.Config) http.Handler {
-		// Call DefaultBuildHandlerChain on the main entrypoint http.Handler
-		// See https://github.com/kubernetes/apiserver/blob/v0.28.0/pkg/server/config.go#L906
-		// DefaultBuildHandlerChain provides many things, notably CORS, HSTS, cache-control, authz and latency tracking
-		requestHandler, err := GetAPIHandler(
-			delegateHandler,
-			c.LoopbackClientConfig,
-			builders)
-		if err != nil {
-			panic(fmt.Sprintf("could not build handler chain func: %s", err.Error()))
-		}
-		return genericapiserver.DefaultBuildHandlerChain(requestHandler, c)
-	}
-
-	k8sVersion, err := getK8sApiserverVersion()
+	err := SetupConfig(serverConfig, builders)
 	if err != nil {
 		return err
 	}
-	before, after, _ := strings.Cut(setting.BuildVersion, ".")
-	serverConfig.Version = &version.Info{
-		Major:        before,
-		Minor:        after,
-		GoVersion:    goruntime.Version(),
-		Platform:     fmt.Sprintf("%s/%s", goruntime.GOOS, goruntime.GOARCH),
-		Compiler:     goruntime.Compiler,
-		GitTreeState: setting.BuildBranch,
-		GitCommit:    setting.BuildCommit,
-		BuildDate:    time.Unix(setting.BuildStamp, 0).UTC().Format(time.DateTime),
-		GitVersion:   k8sVersion,
-	}
 
 	// Create the server
 	server, err := serverConfig.Complete().New("grafana-apiserver", genericapiserver.NewEmptyDelegate())
@@ -380,18 +331,9 @@ func (s *service) start(ctx context.Context) error {
 	}
 
 	// Install the API Group+version
-	for _, b := range builders {
-		g, err := b.GetAPIGroupInfo(Scheme, Codecs, serverConfig.RESTOptionsGetter)
-		if err != nil {
-			return err
-		}
-		if g == nil || len(g.PrioritizedVersions) < 1 {
-			continue
-		}
-		err = server.InstallAPIGroup(g)
-		if err != nil {
-			return err
-		}
+	err = InstallAPIs(server, serverConfig.RESTOptionsGetter, builders)
+	if err != nil {
+		return err
 	}
 
 	// Used by the proxy wrapper registered in ProvideService