K8s: Update OpenAPI post processing structures (#79553)

* add prefix

* update extra paths

pkg/registry/apis/example/register.go

@@ -103,7 +103,7 @@ func (b *TestingAPIBuilder) GetAPIRoutes() *grafanaapiserver.APIRoutes {
 	return &grafanaapiserver.APIRoutes{
 		Root: []grafanaapiserver.APIRouteHandler{
 			{
-				Path: "/aaa",
+				Path: "aaa",
 				Spec: &spec3.PathProps{
 					Summary:     "an example at the root level",
 					Description: "longer description here?",
@@ -144,7 +144,7 @@ func (b *TestingAPIBuilder) GetAPIRoutes() *grafanaapiserver.APIRoutes {
 				},
 			},
 			{
-				Path: "/bbb",
+				Path: "bbb",
 				Spec: &spec3.PathProps{
 					Summary:     "an example at the root level",
 					Description: "longer description here?",
@@ -165,7 +165,7 @@ func (b *TestingAPIBuilder) GetAPIRoutes() *grafanaapiserver.APIRoutes {
 		},
 		Namespace: []grafanaapiserver.APIRouteHandler{
 			{
-				Path: "/ccc",
+				Path: "ccc",
 				Spec: &spec3.PathProps{
 					Summary:     "an example at the root level",
 					Description: "longer description here?",

pkg/services/grafana-apiserver/request_handler.go

@@ -3,21 +3,22 @@ package grafanaapiserver
 import (
 	"fmt"
 	"net/http"
-	"strings"
 
 	"github.com/gorilla/mux"
 	restclient "k8s.io/client-go/rest"
 	"k8s.io/kube-openapi/pkg/spec3"
+	"k8s.io/kube-openapi/pkg/validation/spec"
+
+	"github.com/grafana/grafana/pkg/setting"
 )
 
 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()
-	var err error
 
 	for _, builder := range builders {
 		routes := builder.GetAPIRoutes()
@@ -31,11 +32,6 @@ func getAPIHandler(delegateHandler http.Handler, restConfig *restclient.Config,
 		// Root handlers
 		var sub *mux.Router
 		for _, route := range routes.Root {
-			err = validPath(route.Path)
-			if err != nil {
-				return nil, err
-			}
-
 			if sub == nil {
 				sub = router.PathPrefix(prefix).Subrouter()
 				sub.MethodNotAllowedHandler = &methodNotAllowedHandler{}
@@ -54,10 +50,6 @@ func getAPIHandler(delegateHandler http.Handler, restConfig *restclient.Config,
 		sub = nil
 		prefix += "/namespaces/{namespace}"
 		for _, route := range routes.Namespace {
-			err = validPath(route.Path)
-			if err != nil {
-				return nil, err
-			}
 			if sub == nil {
 				sub = router.PathPrefix(prefix).Subrouter()
 				sub.MethodNotAllowedHandler = &methodNotAllowedHandler{}
@@ -86,17 +78,6 @@ func getAPIHandler(delegateHandler http.Handler, restConfig *restclient.Config,
 	}, nil
 }
 
-// The registered path must start with a slash, and (for now) not have any more
-func validPath(p string) error {
-	if !strings.HasPrefix(p, "/") {
-		return fmt.Errorf("path must start with slash")
-	}
-	if strings.Count(p, "/") > 1 {
-		return fmt.Errorf("path can only have one slash (for now)")
-	}
-	return nil
-}
-
 func (h *requestHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
 	h.router.ServeHTTP(w, req)
 }
@@ -146,15 +127,26 @@ func GetOpenAPIPostProcessor(builders []APIGroupBuilder) func(*spec3.OpenAPI) (*
 		}
 		for _, builder := range builders {
 			routes := builder.GetAPIRoutes()
-			if routes == nil {
-				continue
-			}
-
 			gv := builder.GetGroupVersion()
-			prefix := "/apis/" + gv.String()
+			prefix := "/apis/" + gv.String() + "/"
 			if s.Paths.Paths[prefix] != nil {
-				copy := *s // will copy the rest of the properties
-				copy.Info.Title = "Grafana API server: " + gv.Group
+				copy := spec3.OpenAPI{
+					Version: s.Version,
+					Info: &spec.Info{
+						InfoProps: spec.InfoProps{
+							Title:   gv.String(),
+							Version: setting.BuildVersion,
+						},
+					},
+					Components:   s.Components,
+					ExternalDocs: s.ExternalDocs,
+					Servers:      s.Servers,
+					Paths:        s.Paths,
+				}
+
+				if routes == nil {
+					routes = &APIRoutes{}
+				}
 
 				for _, route := range routes.Root {
 					copy.Paths.Paths[prefix+route.Path] = &spec3.Path{
@@ -163,7 +155,7 @@ func GetOpenAPIPostProcessor(builders []APIGroupBuilder) func(*spec3.OpenAPI) (*
 				}
 
 				for _, route := range routes.Namespace {
-					copy.Paths.Paths[prefix+"/namespaces/{namespace}"+route.Path] = &spec3.Path{
+					copy.Paths.Paths[prefix+"namespaces/{namespace}/"+route.Path] = &spec3.Path{
 						PathProps: *route.Spec,
 					}
 				}

pkg/services/grafana-apiserver/service.go

@@ -339,7 +339,7 @@ func (s *service) start(ctx context.Context) error {
 		// 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(
+		requestHandler, err := GetAPIHandler(
 			delegateHandler,
 			c.LoopbackClientConfig,
 			builders)