API Server - pass path name in context of create request for subresource

Allows a REST storage for a subresource to obtain name in path from
request.

pkg/api/rest/rest.go

@@ -28,6 +28,25 @@ import (
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/watch"
 )
 
+//TODO:
+// Storage interfaces need to be separated into two groups; those that operate
+// on collections and those that operate on individually named items.
+// Collection interfaces:
+// (Method: Current -> Proposed)
+//    GET: Lister -> CollectionGetter
+//    WATCH: Watcher -> CollectionWatcher
+//    CREATE: Creater -> CollectionCreater
+//    DELETE: (n/a) -> CollectionDeleter
+//    UPDATE: (n/a) -> CollectionUpdater
+//
+// Single item interfaces:
+// (Method: Current -> Proposed)
+//    GET: Getter -> NamedGetter
+//    WATCH: (n/a) -> NamedWatcher
+//    CREATE: (n/a) -> NamedCreater
+//    DELETE: Deleter -> NamedDeleter
+//    UPDATE: Update -> NamedUpdater
+
 // Storage is a generic interface for RESTful storage services.
 // Resources which are exported to the RESTful API of apiserver need to implement this interface. It is expected
 // that objects may implement any of the below interfaces.
@@ -117,6 +136,18 @@ type Creater interface {
 	Create(ctx api.Context, obj runtime.Object) (runtime.Object, error)
 }
 
+// NamedCreater is an object that can create an instance of a RESTful object using a name parameter.
+type NamedCreater interface {
+	// New returns an empty object that can be used with Create after request data has been put into it.
+	// This object must be a pointer type for use with Codec.DecodeInto([]byte, runtime.Object)
+	New() runtime.Object
+
+	// Create creates a new version of a resource. It expects a name parameter from the path.
+	// This is needed for create operations on subresources which include the name of the parent
+	// resource in the path.
+	Create(ctx api.Context, name string, obj runtime.Object) (runtime.Object, error)
+}
+
 // Updater is an object that can update an instance of a RESTful object.
 type Updater interface {
 	// New returns an empty object that can be used with Update after request data has been put into it.

pkg/apiserver/api_installer.go

@@ -130,6 +130,7 @@ func (a *APIInstaller) registerResourceHandlers(path string, storage rest.Storag
 
 	// what verbs are supported by the storage, used to know what verbs we support per path
 	creater, isCreater := storage.(rest.Creater)
+	namedCreater, isNamedCreater := storage.(rest.NamedCreater)
 	lister, isLister := storage.(rest.Lister)
 	getter, isGetter := storage.(rest.Getter)
 	getterWithOptions, isGetterWithOptions := storage.(rest.GetterWithOptions)
@@ -145,6 +146,10 @@ func (a *APIInstaller) registerResourceHandlers(path string, storage rest.Storag
 		storageMeta = defaultStorageMetadata{}
 	}
 
+	if isNamedCreater {
+		isCreater = true
+	}
+
 	var versionedList interface{}
 	if isLister {
 		list := lister.NewList()
@@ -436,7 +441,13 @@ func (a *APIInstaller) registerResourceHandlers(path string, storage rest.Storag
 			addParams(route, action.Params)
 			ws.Route(route)
 		case "POST": // Create a resource.
-			route := ws.POST(action.Path).To(CreateResource(creater, reqScope, a.group.Typer, admit)).
+			var handler restful.RouteFunction
+			if isNamedCreater {
+				handler = CreateNamedResource(namedCreater, reqScope, a.group.Typer, admit)
+			} else {
+				handler = CreateResource(creater, reqScope, a.group.Typer, admit)
+			}
+			route := ws.POST(action.Path).To(handler).
 				Filter(m).
 				Doc("create a "+kind).
 				Operation("create"+kind).

pkg/apiserver/apiserver_test.go

@@ -531,6 +531,25 @@ func (r *GetWithOptionsRESTStorage) NewGetOptions() (runtime.Object, bool, strin
 
 var _ rest.GetterWithOptions = &GetWithOptionsRESTStorage{}
 
+type NamedCreaterRESTStorage struct {
+	*SimpleRESTStorage
+	createdName string
+}
+
+func (storage *NamedCreaterRESTStorage) Create(ctx api.Context, name string, obj runtime.Object) (runtime.Object, error) {
+	storage.checkContext(ctx)
+	storage.created = obj.(*Simple)
+	storage.createdName = name
+	if err := storage.errors["create"]; err != nil {
+		return nil, err
+	}
+	var err error
+	if storage.injectedFunction != nil {
+		obj, err = storage.injectedFunction(obj)
+	}
+	return obj, err
+}
+
 func extractBody(response *http.Response, object runtime.Object) (string, error) {
 	defer response.Body.Close()
 	body, err := ioutil.ReadAll(response.Body)
@@ -1810,6 +1829,32 @@ func TestCreateChecksDecode(t *testing.T) {
 	}
 }
 
+func TestCreateWithName(t *testing.T) {
+	pathName := "helloworld"
+	storage := &NamedCreaterRESTStorage{SimpleRESTStorage: &SimpleRESTStorage{}}
+	handler := handle(map[string]rest.Storage{"simple/sub": storage})
+	server := httptest.NewServer(handler)
+	defer server.Close()
+	client := http.Client{}
+
+	simple := &Simple{Other: "foo"}
+	data, _ := codec.Encode(simple)
+	request, err := http.NewRequest("POST", server.URL+"/api/version/simple/"+pathName+"/sub", bytes.NewBuffer(data))
+	if err != nil {
+		t.Errorf("unexpected error: %v", err)
+	}
+	response, err := client.Do(request)
+	if err != nil {
+		t.Errorf("unexpected error: %v", err)
+	}
+	if response.StatusCode != http.StatusCreated {
+		t.Errorf("Unexpected response %#v", response)
+	}
+	if storage.createdName != pathName {
+		t.Errorf("Did not get expected name in create context. Got: %s, Expected: %s", storage.createdName, pathName)
+	}
+}
+
 func TestUpdateChecksDecode(t *testing.T) {
 	handler := handle(map[string]rest.Storage{"simple": &SimpleRESTStorage{}})
 	server := httptest.NewServer(handler)

pkg/apiserver/resthandler.go

@@ -256,19 +256,27 @@ func ListResource(r rest.Lister, rw rest.Watcher, scope RequestScope, forceWatch
 	}
 }
 
-// CreateResource returns a function that will handle a resource creation.
-func CreateResource(r rest.Creater, scope RequestScope, typer runtime.ObjectTyper, admit admission.Interface) restful.RouteFunction {
+func createHandler(r rest.NamedCreater, scope RequestScope, typer runtime.ObjectTyper, admit admission.Interface, includeName bool) restful.RouteFunction {
 	return func(req *restful.Request, res *restful.Response) {
 		w := res.ResponseWriter
 
 		// TODO: we either want to remove timeout or document it (if we document, move timeout out of this function and declare it in api_installer)
 		timeout := parseTimeout(req.Request.URL.Query().Get("timeout"))
 
-		namespace, err := scope.Namer.Namespace(req)
+		var (
+			namespace, name string
+			err             error
+		)
+		if includeName {
+			namespace, name, err = scope.Namer.Name(req)
+		} else {
+			namespace, err = scope.Namer.Namespace(req)
+		}
 		if err != nil {
 			errorJSON(err, scope.Codec, w)
 			return
 		}
+
 		ctx := scope.ContextFunc(req)
 		ctx = api.WithNamespace(ctx, namespace)
 
@@ -292,7 +300,7 @@ func CreateResource(r rest.Creater, scope RequestScope, typer runtime.ObjectType
 		}
 
 		result, err := finishRequest(timeout, func() (runtime.Object, error) {
-			out, err := r.Create(ctx, obj)
+			out, err := r.Create(ctx, name, obj)
 			if status, ok := out.(*api.Status); ok && err == nil && status.Code == 0 {
 				status.Code = http.StatusCreated
 			}
@@ -312,6 +320,24 @@ func CreateResource(r rest.Creater, scope RequestScope, typer runtime.ObjectType
 	}
 }
 
+// CreateNamedResource returns a function that will handle a resource creation with name.
+func CreateNamedResource(r rest.NamedCreater, scope RequestScope, typer runtime.ObjectTyper, admit admission.Interface) restful.RouteFunction {
+	return createHandler(r, scope, typer, admit, true)
+}
+
+// CreateResource returns a function that will handle a resource creation.
+func CreateResource(r rest.Creater, scope RequestScope, typer runtime.ObjectTyper, admit admission.Interface) restful.RouteFunction {
+	return createHandler(&namedCreaterAdapter{r}, scope, typer, admit, false)
+}
+
+type namedCreaterAdapter struct {
+	rest.Creater
+}
+
+func (c *namedCreaterAdapter) Create(ctx api.Context, name string, obj runtime.Object) (runtime.Object, error) {
+	return c.Creater.Create(ctx, obj)
+}
+
 // PatchResource returns a function that will handle a resource patch
 // TODO: Eventually PatchResource should just use GuaranteedUpdate and this routine should be a bit cleaner
 func PatchResource(r rest.Patcher, scope RequestScope, typer runtime.ObjectTyper, admit admission.Interface, converter runtime.ObjectConvertor) restful.RouteFunction {