Add MethodNotSupported error

pkg/api/errors/errors.go

@@ -159,6 +159,19 @@ func NewBadRequest(reason string) error {
 	}}
 }
 
+// NewMethodNotSupported returns an error indicating the requested action is not supported on this kind.
+func NewMethodNotSupported(kind, action string) error {
+	return &StatusError{api.Status{
+		Status: api.StatusFailure,
+		Code:   http.StatusMethodNotAllowed,
+		Reason: api.StatusReasonMethodNotAllowed,
+		Details: &api.StatusDetails{
+			Kind: kind,
+		},
+		Message: fmt.Sprintf("%s is not supported on resources of kind %q", action, kind),
+	}}
+}
+
 // NewInternalError returns an error indicating the item is invalid and cannot be processed.
 func NewInternalError(err error) error {
 	return &StatusError{api.Status{
@@ -192,6 +205,12 @@ func IsInvalid(err error) bool {
 	return reasonForError(err) == api.StatusReasonInvalid
 }
 
+// IsMethodNotSupported determines if the err is an error which indicates the provided action could not
+// be performed because it is not supported by the server.
+func IsMethodNotSupported(err error) bool {
+	return reasonForError(err) == api.StatusReasonMethodNotAllowed
+}
+
 // IsBadRequest determines if err is an error which indicates that the request is invalid.
 func IsBadRequest(err error) bool {
 	return reasonForError(err) == api.StatusReasonBadRequest

pkg/api/errors/errors_test.go

@@ -40,6 +40,12 @@ func TestErrorNew(t *testing.T) {
 	if IsInvalid(err) {
 		t.Errorf("expected to not be %s", api.StatusReasonInvalid)
 	}
+	if IsBadRequest(err) {
+		t.Errorf("expected to not be %s", api.StatusReasonBadRequest)
+	}
+	if IsMethodNotSupported(err) {
+		t.Errorf("expected to not be %s", api.StatusReasonMethodNotAllowed)
+	}
 
 	if !IsConflict(NewConflict("test", "2", errors.New("message"))) {
 		t.Errorf("expected to be conflict")
@@ -50,6 +56,12 @@ func TestErrorNew(t *testing.T) {
 	if !IsInvalid(NewInvalid("test", "2", nil)) {
 		t.Errorf("expected to be %s", api.StatusReasonInvalid)
 	}
+	if !IsBadRequest(NewBadRequest("reason")) {
+		t.Errorf("expected to be %s", api.StatusReasonBadRequest)
+	}
+	if !IsMethodNotSupported(NewMethodNotSupported("foo", "delete")) {
+		t.Errorf("expected to be %s", api.StatusReasonMethodNotAllowed)
+	}
 }
 
 func TestNewInvalid(t *testing.T) {

pkg/api/types.go

@@ -931,6 +931,11 @@ const (
 	// data was invalid.  API calls that return BadRequest can never succeed.
 	StatusReasonBadRequest StatusReason = "BadRequest"
 
+	// StatusReasonMethodNotAllowed means that the action the client attempted to perform on the
+	// resource was not supported by the code - for instance, attempting to delete a resource that
+	// can only be created. API calls that return MethodNotAllowed can never succeed.
+	StatusReasonMethodNotAllowed StatusReason = "MethodNotAllowed"
+
 	// StatusReasonInternalError indicates that an internal error occurred, it is unexpected
 	// and the outcome of the call is unknown.
 	// Details (optional):