Expose openapi schema to handlers

staging/src/k8s.io/apiserver/pkg/endpoints/groupversion.go

@@ -30,6 +30,7 @@ import (
 	"k8s.io/apiserver/pkg/admission"
 	"k8s.io/apiserver/pkg/endpoints/discovery"
 	"k8s.io/apiserver/pkg/registry/rest"
+	openapicommon "k8s.io/kube-openapi/pkg/common"
 )
 
 // APIGroupVersion is a helper for exposing rest.Storage objects as http.Handlers via go-restful
@@ -77,6 +78,9 @@ type APIGroupVersion struct {
 	// EnableAPIResponseCompression indicates whether API Responses should support compression
 	// if the client requests it via Accept-Encoding
 	EnableAPIResponseCompression bool
+
+	// OpenAPIConfig lets the individual handlers build a subset of the OpenAPI schema before they are installed.
+	OpenAPIConfig *openapicommon.Config
 }
 
 // InstallREST registers the REST handlers (storage, watch, proxy and redirect) into a restful Container.

staging/src/k8s.io/apiserver/pkg/endpoints/handlers/rest.go

@@ -39,6 +39,7 @@ import (
 	"k8s.io/apiserver/pkg/endpoints/metrics"
 	"k8s.io/apiserver/pkg/endpoints/request"
 	"k8s.io/apiserver/pkg/registry/rest"
+	openapiproto "k8s.io/kube-openapi/pkg/util/proto"
 )
 
 // RequestScope encapsulates common fields across all RESTful handler methods.
@@ -55,6 +56,7 @@ type RequestScope struct {
 	UnsafeConvertor runtime.ObjectConvertor
 
 	TableConvertor rest.TableConvertor
+	OpenAPISchema  openapiproto.Schema
 
 	Resource    schema.GroupVersionResource
 	Kind        schema.GroupVersionKind

staging/src/k8s.io/apiserver/pkg/endpoints/installer.go

@@ -39,6 +39,8 @@ import (
 	"k8s.io/apiserver/pkg/endpoints/metrics"
 	"k8s.io/apiserver/pkg/registry/rest"
 	genericfilters "k8s.io/apiserver/pkg/server/filters"
+	utilopenapi "k8s.io/apiserver/pkg/util/openapi"
+	openapibuilder "k8s.io/kube-openapi/pkg/builder"
 )
 
 const (
@@ -495,6 +497,16 @@ func (a *APIInstaller) registerResourceHandlers(path string, storage rest.Storag
 	if a.group.MetaGroupVersion != nil {
 		reqScope.MetaGroupVersion = *a.group.MetaGroupVersion
 	}
+	if a.group.OpenAPIConfig != nil {
+		openAPIDefinitions, err := openapibuilder.BuildOpenAPIDefinitionsForResource(defaultVersionedObject, a.group.OpenAPIConfig)
+		if err != nil {
+			return nil, fmt.Errorf("unable to build openapi definitions for %v: %v", fqKindToRegister, err)
+		}
+		reqScope.OpenAPISchema, err = utilopenapi.ToProtoSchema(openAPIDefinitions, fqKindToRegister)
+		if err != nil {
+			return nil, fmt.Errorf("unable to get openapi schema for %v: %v", fqKindToRegister, err)
+		}
+	}
 	for _, action := range actions {
 		producedObject := storageMeta.ProducesObject(action.Verb)
 		if producedObject == nil {

staging/src/k8s.io/apiserver/pkg/server/genericapiserver.go

@@ -426,6 +426,7 @@ func (s *GenericAPIServer) newAPIGroupVersion(apiGroupInfo *APIGroupInfo, groupV
 		Admit:                        s.admissionControl,
 		MinRequestTimeout:            s.minRequestTimeout,
 		EnableAPIResponseCompression: s.enableAPIResponseCompression,
+		OpenAPIConfig:                s.openAPIConfig,
 	}
 }
 

staging/src/k8s.io/apiserver/pkg/server/genericapiserver_test.go

@@ -31,6 +31,7 @@ import (
 	"testing"
 	"time"
 
+	openapi "github.com/go-openapi/spec"
 	"github.com/stretchr/testify/assert"
 
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
@@ -78,9 +79,45 @@ func init() {
 	examplev1.AddToScheme(scheme)
 }
 
+func buildTestOpenAPIDefinition() kubeopenapi.OpenAPIDefinition {
+	return kubeopenapi.OpenAPIDefinition{
+		Schema: openapi.Schema{
+			SchemaProps: openapi.SchemaProps{
+				Description: "Description",
+				Properties:  map[string]openapi.Schema{},
+			},
+			VendorExtensible: openapi.VendorExtensible{
+				Extensions: openapi.Extensions{
+					"x-kubernetes-group-version-kind": []map[string]string{
+						{
+							"group":   "",
+							"version": "v1",
+							"kind":    "Getter",
+						},
+						{
+							"group":   "batch",
+							"version": "v1",
+							"kind":    "Getter",
+						},
+						{
+							"group":   "extensions",
+							"version": "v1",
+							"kind":    "Getter",
+						},
+					},
+				},
+			},
+		},
+	}
+}
+
 func testGetOpenAPIDefinitions(_ kubeopenapi.ReferenceCallback) map[string]kubeopenapi.OpenAPIDefinition {
 	return map[string]kubeopenapi.OpenAPIDefinition{
-		"k8s.io/apimachinery/pkg/apis/meta/v1.APIGroupList": {},
+		"k8s.io/apimachinery/pkg/apis/meta/v1.Status":          {},
+		"k8s.io/apimachinery/pkg/apis/meta/v1.APIVersions":     {},
+		"k8s.io/apimachinery/pkg/apis/meta/v1.APIGroupList":    {},
+		"k8s.io/apimachinery/pkg/apis/meta/v1.APIGroup":        buildTestOpenAPIDefinition(),
+		"k8s.io/apimachinery/pkg/apis/meta/v1.APIResourceList": {},
 	}
 }
 

staging/src/k8s.io/apiserver/pkg/util/openapi/proto.go

@@ -0,0 +1,142 @@
+/*
+Copyright 2018 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package openapi
+
+import (
+	"encoding/json"
+	"fmt"
+
+	"github.com/go-openapi/spec"
+	openapi_v2 "github.com/googleapis/gnostic/OpenAPIv2"
+	"github.com/googleapis/gnostic/compiler"
+	yaml "gopkg.in/yaml.v2"
+
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/kube-openapi/pkg/util/proto"
+)
+
+const (
+	// groupVersionKindExtensionKey is the key used to lookup the
+	// GroupVersionKind value for an object definition from the
+	// definition's "extensions" map.
+	groupVersionKindExtensionKey = "x-kubernetes-group-version-kind"
+)
+
+// ToProtoSchema builds the proto formatted schema from an OpenAPI spec
+func ToProtoSchema(openAPIDefinitions *spec.Definitions, gvk schema.GroupVersionKind) (proto.Schema, error) {
+	openAPISpec := newMinimalValidOpenAPISpec()
+	openAPISpec.Definitions = *openAPIDefinitions
+
+	specBytes, err := json.MarshalIndent(openAPISpec, " ", " ")
+	if err != nil {
+		return nil, err
+	}
+
+	var info yaml.MapSlice
+	err = yaml.Unmarshal(specBytes, &info)
+	if err != nil {
+		return nil, err
+	}
+
+	doc, err := openapi_v2.NewDocument(info, compiler.NewContext("$root", nil))
+	if err != nil {
+		return nil, err
+	}
+
+	models, err := proto.NewOpenAPIData(doc)
+	if err != nil {
+		return nil, err
+	}
+
+	for _, modelName := range models.ListModels() {
+		model := models.LookupModel(modelName)
+		if model == nil {
+			return nil, fmt.Errorf("the ListModels function returned a model that can't be looked-up")
+		}
+		gvkList := parseGroupVersionKind(model)
+		for _, modelGVK := range gvkList {
+			if modelGVK == gvk {
+				return model, nil
+			}
+		}
+	}
+
+	return nil, fmt.Errorf("no model found with a %v tag matching %v", groupVersionKindExtensionKey, gvk)
+}
+
+// newMinimalValidOpenAPISpec creates a minimal openapi spec with only the required fields filled in
+func newMinimalValidOpenAPISpec() *spec.Swagger {
+	return &spec.Swagger{
+		SwaggerProps: spec.SwaggerProps{
+			Swagger: "2.0",
+			Info: &spec.Info{
+				InfoProps: spec.InfoProps{
+					Title:   "Kubernetes",
+					Version: "0.0.0",
+				},
+			},
+		},
+	}
+}
+
+// parseGroupVersionKind gets and parses GroupVersionKind from the extension. Returns empty if it doesn't have one.
+func parseGroupVersionKind(s proto.Schema) []schema.GroupVersionKind {
+	extensions := s.GetExtensions()
+
+	gvkListResult := []schema.GroupVersionKind{}
+
+	// Get the extensions
+	gvkExtension, ok := extensions[groupVersionKindExtensionKey]
+	if !ok {
+		return []schema.GroupVersionKind{}
+	}
+
+	// gvk extension must be a list of at least 1 element.
+	gvkList, ok := gvkExtension.([]interface{})
+	if !ok {
+		return []schema.GroupVersionKind{}
+	}
+
+	for _, gvk := range gvkList {
+		// gvk extension list must be a map with group, version, and
+		// kind fields
+		gvkMap, ok := gvk.(map[interface{}]interface{})
+		if !ok {
+			continue
+		}
+		group, ok := gvkMap["group"].(string)
+		if !ok {
+			continue
+		}
+		version, ok := gvkMap["version"].(string)
+		if !ok {
+			continue
+		}
+		kind, ok := gvkMap["kind"].(string)
+		if !ok {
+			continue
+		}
+
+		gvkListResult = append(gvkListResult, schema.GroupVersionKind{
+			Group:   group,
+			Version: version,
+			Kind:    kind,
+		})
+	}
+
+	return gvkListResult
+}

staging/src/k8s.io/apiserver/pkg/util/openapi/proto_test.go

@@ -0,0 +1,77 @@
+/*
+Copyright 2018 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package openapi
+
+import (
+	"reflect"
+	"testing"
+
+	"github.com/go-openapi/spec"
+
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/kube-openapi/pkg/util/proto"
+)
+
+// TestOpenAPIDefinitionsToProtoSchema tests the openapi parser
+func TestOpenAPIDefinitionsToProtoSchema(t *testing.T) {
+	openAPIDefinitions := &spec.Definitions{
+		"io.k8s.api.testgroup.v1.Foo": spec.Schema{
+			SchemaProps: spec.SchemaProps{
+				Description: "Description of Foos",
+				Properties:  map[string]spec.Schema{},
+			},
+			VendorExtensible: spec.VendorExtensible{
+				Extensions: spec.Extensions{
+					"x-kubernetes-group-version-kind": []map[string]string{
+						{
+							"group":   "testgroup.k8s.io",
+							"version": "v1",
+							"kind":    "Foo",
+						},
+					},
+				},
+			},
+		},
+	}
+	gvk := schema.GroupVersionKind{
+		Group:   "testgroup.k8s.io",
+		Version: "v1",
+		Kind:    "Foo",
+	}
+	expectedSchema := &proto.Arbitrary{
+		BaseSchema: proto.BaseSchema{
+			Description: "Description of Foos",
+			Extensions: map[string]interface{}{
+				"x-kubernetes-group-version-kind": []interface{}{
+					map[interface{}]interface{}{
+						"group":   "testgroup.k8s.io",
+						"version": "v1",
+						"kind":    "Foo",
+					},
+				},
+			},
+			Path: proto.NewPath("io.k8s.api.testgroup.v1.Foo"),
+		},
+	}
+	actualSchema, err := ToProtoSchema(openAPIDefinitions, gvk)
+	if err != nil {
+		t.Fatalf("expected ToProtoSchema not to return an error")
+	}
+	if !reflect.DeepEqual(expectedSchema, actualSchema) {
+		t.Fatalf("expected schema:\n%v\nbut got:\n%v", expectedSchema, actualSchema)
+	}
+}