Create a separate conversion function for the field labels used by downward API

pkg/apis/core/BUILD

@@ -51,6 +51,7 @@ filegroup(
         "//pkg/apis/core/fuzzer:all-srcs",
         "//pkg/apis/core/helper:all-srcs",
         "//pkg/apis/core/install:all-srcs",
+        "//pkg/apis/core/pods:all-srcs",
         "//pkg/apis/core/v1:all-srcs",
         "//pkg/apis/core/validation:all-srcs",
     ],

pkg/apis/core/pods/BUILD

+load("@io_bazel_rules_go//go:def.bzl", "go_library", "go_test")
+
+go_library(
+    name = "go_default_library",
+    srcs = ["helpers.go"],
+    importpath = "k8s.io/kubernetes/pkg/apis/core/pods",
+    visibility = ["//visibility:public"],
+    deps = ["//pkg/fieldpath:go_default_library"],
+)
+
+go_test(
+    name = "go_default_test",
+    srcs = ["helpers_test.go"],
+    importpath = "k8s.io/kubernetes/pkg/apis/core/pods",
+    library = ":go_default_library",
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+    visibility = ["//visibility:public"],
+)

pkg/apis/core/pods/helpers.go

+/*
+Copyright 2017 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 pods
+
+import (
+	"fmt"
+
+	"k8s.io/kubernetes/pkg/fieldpath"
+)
+
+func ConvertDownwardAPIFieldLabel(version, label, value string) (string, string, error) {
+	if version != "v1" {
+		return "", "", fmt.Errorf("unsupported pod version: %s", version)
+	}
+
+	path, _ := fieldpath.SplitMaybeSubscriptedPath(label)
+	switch path {
+	case "metadata.annotations",
+		"metadata.labels",
+		"metadata.name",
+		"metadata.namespace",
+		"metadata.uid",
+		"spec.nodeName",
+		"spec.restartPolicy",
+		"spec.serviceAccountName",
+		"spec.schedulerName",
+		"status.phase",
+		"status.hostIP",
+		"status.podIP":
+		return label, value, nil
+	// This is for backwards compatibility with old v1 clients which send spec.host
+	case "spec.host":
+		return "spec.nodeName", value, nil
+	default:
+		return "", "", fmt.Errorf("field label not supported: %s", label)
+	}
+}

pkg/apis/core/pods/helpers_test.go

+/*
+Copyright 2017 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 pods
+
+import (
+	"testing"
+)
+
+func TestConvertDownwardAPIFieldLabel(t *testing.T) {
+	testCases := []struct {
+		version       string
+		label         string
+		value         string
+		expectedErr   bool
+		expectedLabel string
+		expectedValue string
+	}{
+		{
+			version:     "v2",
+			label:       "metadata.name",
+			value:       "test-pod",
+			expectedErr: true,
+		},
+		{
+			version:     "v1",
+			label:       "invalid-label",
+			value:       "value",
+			expectedErr: true,
+		},
+		{
+			version:       "v1",
+			label:         "metadata.name",
+			value:         "test-pod",
+			expectedLabel: "metadata.name",
+			expectedValue: "test-pod",
+		},
+		{
+			version:       "v1",
+			label:         "metadata.annotations",
+			value:         "myValue",
+			expectedLabel: "metadata.annotations",
+			expectedValue: "myValue",
+		},
+		{
+			version:       "v1",
+			label:         "metadata.annotations['myKey']",
+			value:         "myValue",
+			expectedLabel: "metadata.annotations['myKey']",
+			expectedValue: "myValue",
+		},
+		{
+			version:       "v1",
+			label:         "spec.host",
+			value:         "127.0.0.1",
+			expectedLabel: "spec.nodeName",
+			expectedValue: "127.0.0.1",
+		},
+	}
+	for _, tc := range testCases {
+		label, value, err := ConvertDownwardAPIFieldLabel(tc.version, tc.label, tc.value)
+		if err != nil {
+			if tc.expectedErr {
+				continue
+			}
+			t.Errorf("ConvertDownwardAPIFieldLabel(%s, %s, %s) failed: %s",
+				tc.version, tc.label, tc.value, err)
+		}
+		if tc.expectedLabel != label || tc.expectedValue != value {
+			t.Errorf("ConvertDownwardAPIFieldLabel(%s, %s, %s) = (%s, %s, nil), expected (%s, %s, nil)",
+				tc.version, tc.label, tc.value, label, value, tc.expectedLabel, tc.expectedValue)
+		}
+	}
+}

pkg/apis/core/v1/conversion.go

@@ -159,17 +159,12 @@ func addConversionFuncs(scheme *runtime.Scheme) error {
 		func(label, value string) (string, string, error) {
 			path, _ := fieldpath.SplitMaybeSubscriptedPath(label)
 			switch path {
-			case "metadata.annotations",
-				"metadata.labels",
-				"metadata.name",
+			case "metadata.name",
 				"metadata.namespace",
-				"metadata.uid",
 				"spec.nodeName",
 				"spec.restartPolicy",
-				"spec.serviceAccountName",
 				"spec.schedulerName",
 				"status.phase",
-				"status.hostIP",
 				"status.podIP":
 				return label, value, nil
 			// This is for backwards compatibility with old v1 clients which send spec.host

pkg/apis/core/validation/BUILD

@@ -18,6 +18,7 @@ go_library(
         "//pkg/api/service:go_default_library",
         "//pkg/apis/core:go_default_library",
         "//pkg/apis/core/helper:go_default_library",
+        "//pkg/apis/core/pods:go_default_library",
         "//pkg/apis/core/v1:go_default_library",
         "//pkg/apis/core/v1/helper:go_default_library",
         "//pkg/capabilities:go_default_library",

pkg/apis/core/validation/validation.go

@@ -42,10 +42,10 @@ import (
 	"k8s.io/apimachinery/pkg/util/validation"
 	"k8s.io/apimachinery/pkg/util/validation/field"
 	utilfeature "k8s.io/apiserver/pkg/util/feature"
-	"k8s.io/kubernetes/pkg/api/legacyscheme"
 	apiservice "k8s.io/kubernetes/pkg/api/service"
 	"k8s.io/kubernetes/pkg/apis/core"
 	"k8s.io/kubernetes/pkg/apis/core/helper"
+	podshelper "k8s.io/kubernetes/pkg/apis/core/pods"
 	corev1 "k8s.io/kubernetes/pkg/apis/core/v1"
 	v1helper "k8s.io/kubernetes/pkg/apis/core/v1/helper"
 	"k8s.io/kubernetes/pkg/capabilities"
@@ -1964,7 +1964,7 @@ func validateObjectFieldSelector(fs *core.ObjectFieldSelector, expressions *sets
 		return allErrs
 	}
 
-	internalFieldPath, _, err := legacyscheme.Scheme.ConvertFieldLabel(fs.APIVersion, "Pod", fs.FieldPath, "")
+	internalFieldPath, _, err := podshelper.ConvertDownwardAPIFieldLabel(fs.APIVersion, fs.FieldPath, "")
 	if err != nil {
 		allErrs = append(allErrs, field.Invalid(fldPath.Child("fieldPath"), fs.FieldPath, fmt.Sprintf("error converting fieldPath: %v", err)))
 		return allErrs

pkg/kubelet/BUILD

@@ -29,10 +29,10 @@ go_library(
     ],
     importpath = "k8s.io/kubernetes/pkg/kubelet",
     deps = [
-        "//pkg/api/legacyscheme:go_default_library",
         "//pkg/api/v1/pod:go_default_library",
         "//pkg/api/v1/resource:go_default_library",
         "//pkg/apis/core:go_default_library",
+        "//pkg/apis/core/pods:go_default_library",
         "//pkg/apis/core/v1:go_default_library",
         "//pkg/apis/core/v1/helper:go_default_library",
         "//pkg/apis/core/v1/helper/qos:go_default_library",

pkg/kubelet/kubelet_pods.go

@@ -43,9 +43,9 @@ import (
 	"k8s.io/apimachinery/pkg/util/validation/field"
 	utilfeature "k8s.io/apiserver/pkg/util/feature"
 	"k8s.io/client-go/tools/remotecommand"
-	"k8s.io/kubernetes/pkg/api/legacyscheme"
 	podutil "k8s.io/kubernetes/pkg/api/v1/pod"
 	"k8s.io/kubernetes/pkg/api/v1/resource"
+	podshelper "k8s.io/kubernetes/pkg/apis/core/pods"
 	v1helper "k8s.io/kubernetes/pkg/apis/core/v1/helper"
 	v1qos "k8s.io/kubernetes/pkg/apis/core/v1/helper/qos"
 	"k8s.io/kubernetes/pkg/apis/core/v1/validation"
@@ -733,7 +733,7 @@ func (kl *Kubelet) makeEnvironmentVariables(pod *v1.Pod, container *v1.Container
 // podFieldSelectorRuntimeValue returns the runtime value of the given
 // selector for a pod.
 func (kl *Kubelet) podFieldSelectorRuntimeValue(fs *v1.ObjectFieldSelector, pod *v1.Pod, podIP string) (string, error) {
-	internalFieldPath, _, err := legacyscheme.Scheme.ConvertFieldLabel(fs.APIVersion, "Pod", fs.FieldPath, "")
+	internalFieldPath, _, err := podshelper.ConvertDownwardAPIFieldLabel(fs.APIVersion, fs.FieldPath, "")
 	if err != nil {
 		return "", err
 	}