kubectl: add --support to get, patch, edit and replace commands

Co-authored-by: Nikhita Raghunath <nikitaraghunath@gmail.com>

Kubernetes-commit: a5aa858d44651ba48bdce634a39b55be91216614

pkg/cmd/edit/edit.go

@@ -63,7 +63,10 @@ var (
 		kubectl edit job.v1.batch/myjob -o json
 
 		# Edit the deployment 'mydeployment' in YAML and save the modified config in its annotation
-		kubectl edit deployment/mydeployment -o yaml --save-config`))
+		kubectl edit deployment/mydeployment -o yaml --save-config
+
+		# Edit the deployment/mydeployment's status subresource
+		kubectl edit deployment mydeployment --subresource='status'`))
 )
 
 // NewCmdEdit creates the `edit` command
@@ -80,6 +83,7 @@ func NewCmdEdit(f cmdutil.Factory, ioStreams genericclioptions.IOStreams) *cobra
 		ValidArgsFunction:     util.ResourceTypeAndNameCompletionFunc(f),
 		Run: func(cmd *cobra.Command, args []string) {
 			cmdutil.CheckErr(o.Complete(f, args, cmd))
+			cmdutil.CheckErr(o.Validate())
 			cmdutil.CheckErr(o.Run())
 		},
 	}
@@ -96,5 +100,6 @@ func NewCmdEdit(f cmdutil.Factory, ioStreams genericclioptions.IOStreams) *cobra
 		"Defaults to the line ending native to your platform.")
 	cmdutil.AddFieldManagerFlagVar(cmd, &o.FieldManager, "kubectl-edit")
 	cmdutil.AddApplyAnnotationVarFlags(cmd, &o.ApplyAnnotation)
+	cmdutil.AddSubresourceFlags(cmd, &o.Subresource, "If specified, edit will operate on the subresource of the requested object.", editor.SupportedSubresources...)
 	return cmd
 }

pkg/cmd/edit/edit_test.go

@@ -53,6 +53,7 @@ type EditTestCase struct {
 	Output           string   `yaml:"outputFormat"`
 	OutputPatch      string   `yaml:"outputPatch"`
 	SaveConfig       string   `yaml:"saveConfig"`
+	Subresource      string   `yaml:"subresource"`
 	Namespace        string   `yaml:"namespace"`
 	ExpectedStdout   []string `yaml:"expectedStdout"`
 	ExpectedStderr   []string `yaml:"expectedStderr"`
@@ -253,6 +254,9 @@ func TestEdit(t *testing.T) {
 			if len(testcase.SaveConfig) > 0 {
 				cmd.Flags().Set("save-config", testcase.SaveConfig)
 			}
+			if len(testcase.Subresource) > 0 {
+				cmd.Flags().Set("subresource", testcase.Subresource)
+			}
 
 			cmdutil.BehaviorOnFatal(func(str string, code int) {
 				errBuf.WriteString(str)

pkg/cmd/edit/testdata/testcase-edit-subresource-status/0.response

@@ -0,0 +1,85 @@
+{
+    "apiVersion": "apps/v1",
+    "kind": "Deployment",
+    "metadata": {
+        "annotations": {
+            "deployment.kubernetes.io/revision": "1"
+        },
+        "creationTimestamp": "2021-06-23T17:01:10Z",
+        "generation": 5,
+        "labels": {
+            "app": "nginx"
+        },
+        "name": "nginx",
+        "namespace": "edit-test",
+        "resourceVersion": "121107",
+        "uid": "a598ee47-9635-482b-bacb-16c9e3ade05c"
+    },
+    "spec": {
+        "progressDeadlineSeconds": 600,
+        "replicas": 3,
+        "revisionHistoryLimit": 10,
+        "selector": {
+            "matchLabels": {
+                "app": "nginx"
+            }
+        },
+        "strategy": {
+            "rollingUpdate": {
+                "maxSurge": "25%",
+                "maxUnavailable": "25%"
+            },
+            "type": "RollingUpdate"
+        },
+        "template": {
+            "metadata": {
+                "creationTimestamp": null,
+                "labels": {
+                    "app": "nginx"
+                }
+            },
+            "spec": {
+                "containers": [
+                    {
+                        "image": "gcr.io/kakaraparthy-devel/nginx:latest",
+                        "imagePullPolicy": "Always",
+                        "name": "nginx",
+                        "resources": {},
+                        "terminationMessagePath": "/dev/termination-log",
+                        "terminationMessagePolicy": "File"
+                    }
+                ],
+                "dnsPolicy": "ClusterFirst",
+                "restartPolicy": "Always",
+                "schedulerName": "default-scheduler",
+                "securityContext": {},
+                "terminationGracePeriodSeconds": 30
+            }
+        }
+    },
+    "status": {
+        "availableReplicas": 3,
+        "conditions": [
+            {
+                "lastTransitionTime": "2021-06-23T17:01:10Z",
+                "lastUpdateTime": "2021-06-23T17:01:18Z",
+                "message": "ReplicaSet \"nginx-6f5fdbd667\" has successfully progressed.",
+                "reason": "NewReplicaSetAvailable",
+                "status": "True",
+                "type": "Progressing"
+            },
+            {
+                "lastTransitionTime": "2021-06-23T17:59:01Z",
+                "lastUpdateTime": "2021-06-23T17:59:01Z",
+                "message": "Deployment has minimum availability.",
+                "reason": "MinimumReplicasAvailable",
+                "status": "True",
+                "type": "Available"
+            }
+        ],
+        "observedGeneration": 5,
+        "readyReplicas": 3,
+        "replicas": 3,
+        "updatedReplicas": 3
+    }
+}

pkg/cmd/edit/testdata/testcase-edit-subresource-status/1.edited

@@ -0,0 +1,66 @@
+# Please edit the object below. Lines beginning with a '#' will be ignored,
+# and an empty file will abort the edit. If an error occurs while saving this file will be
+# reopened with the relevant failures.
+#
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  annotations:
+    deployment.kubernetes.io/revision: "1"
+  creationTimestamp: "2021-06-23T17:01:10Z"
+  generation: 5
+  labels:
+    app: nginx
+  name: nginx
+  namespace: edit-test
+  resourceVersion: "121107"
+  uid: a598ee47-9635-482b-bacb-16c9e3ade05c
+spec:
+  progressDeadlineSeconds: 600
+  replicas: 3
+  revisionHistoryLimit: 10
+  selector:
+    matchLabels:
+      app: nginx
+  strategy:
+    rollingUpdate:
+      maxSurge: 25%
+      maxUnavailable: 25%
+    type: RollingUpdate
+  template:
+    metadata:
+      creationTimestamp: null
+      labels:
+        app: nginx
+    spec:
+      containers:
+      - image: gcr.io/kakaraparthy-devel/nginx:latest
+        imagePullPolicy: Always
+        name: nginx
+        resources: {}
+        terminationMessagePath: /dev/termination-log
+        terminationMessagePolicy: File
+      dnsPolicy: ClusterFirst
+      restartPolicy: Always
+      schedulerName: default-scheduler
+      securityContext: {}
+      terminationGracePeriodSeconds: 30
+status:
+  availableReplicas: 3
+  conditions:
+  - lastTransitionTime: "2021-06-23T17:01:10Z"
+    lastUpdateTime: "2021-06-23T17:01:18Z"
+    message: ReplicaSet "nginx-6f5fdbd667" has successfully progressed.
+    reason: NewReplicaSetAvailable
+    status: "True"
+    type: Progressing
+  - lastTransitionTime: "2021-06-23T17:59:01Z"
+    lastUpdateTime: "2021-06-23T17:59:01Z"
+    message: Deployment has minimum availability.
+    reason: MinimumReplicasAvailable
+    status: "True"
+    type: Available
+  observedGeneration: 5
+  readyReplicas: 3
+  replicas: 4
+  updatedReplicas: 3

pkg/cmd/edit/testdata/testcase-edit-subresource-status/1.original

@@ -0,0 +1,66 @@
+# Please edit the object below. Lines beginning with a '#' will be ignored,
+# and an empty file will abort the edit. If an error occurs while saving this file will be
+# reopened with the relevant failures.
+#
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  annotations:
+    deployment.kubernetes.io/revision: "1"
+  creationTimestamp: "2021-06-23T17:01:10Z"
+  generation: 5
+  labels:
+    app: nginx
+  name: nginx
+  namespace: edit-test
+  resourceVersion: "121107"
+  uid: a598ee47-9635-482b-bacb-16c9e3ade05c
+spec:
+  progressDeadlineSeconds: 600
+  replicas: 3
+  revisionHistoryLimit: 10
+  selector:
+    matchLabels:
+      app: nginx
+  strategy:
+    rollingUpdate:
+      maxSurge: 25%
+      maxUnavailable: 25%
+    type: RollingUpdate
+  template:
+    metadata:
+      creationTimestamp: null
+      labels:
+        app: nginx
+    spec:
+      containers:
+      - image: gcr.io/kakaraparthy-devel/nginx:latest
+        imagePullPolicy: Always
+        name: nginx
+        resources: {}
+        terminationMessagePath: /dev/termination-log
+        terminationMessagePolicy: File
+      dnsPolicy: ClusterFirst
+      restartPolicy: Always
+      schedulerName: default-scheduler
+      securityContext: {}
+      terminationGracePeriodSeconds: 30
+status:
+  availableReplicas: 3
+  conditions:
+  - lastTransitionTime: "2021-06-23T17:01:10Z"
+    lastUpdateTime: "2021-06-23T17:01:18Z"
+    message: ReplicaSet "nginx-6f5fdbd667" has successfully progressed.
+    reason: NewReplicaSetAvailable
+    status: "True"
+    type: Progressing
+  - lastTransitionTime: "2021-06-23T17:59:01Z"
+    lastUpdateTime: "2021-06-23T17:59:01Z"
+    message: Deployment has minimum availability.
+    reason: MinimumReplicasAvailable
+    status: "True"
+    type: Available
+  observedGeneration: 5
+  readyReplicas: 3
+  replicas: 3
+  updatedReplicas: 3

pkg/cmd/edit/testdata/testcase-edit-subresource-status/2.request

@@ -0,0 +1,5 @@
+{
+  "status": {
+    "replicas": 4
+  }
+}

pkg/cmd/edit/testdata/testcase-edit-subresource-status/2.response

@@ -0,0 +1,85 @@
+{
+    "apiVersion": "apps/v1",
+    "kind": "Deployment",
+    "metadata": {
+        "annotations": {
+            "deployment.kubernetes.io/revision": "1"
+        },
+        "creationTimestamp": "2021-06-23T17:01:10Z",
+        "generation": 5,
+        "labels": {
+            "app": "nginx"
+        },
+        "name": "nginx",
+        "namespace": "edit-test",
+        "resourceVersion": "121107",
+        "uid": "a598ee47-9635-482b-bacb-16c9e3ade05c"
+    },
+    "spec": {
+        "progressDeadlineSeconds": 600,
+        "replicas": 3,
+        "revisionHistoryLimit": 10,
+        "selector": {
+            "matchLabels": {
+                "app": "nginx"
+            }
+        },
+        "strategy": {
+            "rollingUpdate": {
+                "maxSurge": "25%",
+                "maxUnavailable": "25%"
+            },
+            "type": "RollingUpdate"
+        },
+        "template": {
+            "metadata": {
+                "creationTimestamp": null,
+                "labels": {
+                    "app": "nginx"
+                }
+            },
+            "spec": {
+                "containers": [
+                    {
+                        "image": "gcr.io/kakaraparthy-devel/nginx:latest",
+                        "imagePullPolicy": "Always",
+                        "name": "nginx",
+                        "resources": {},
+                        "terminationMessagePath": "/dev/termination-log",
+                        "terminationMessagePolicy": "File"
+                    }
+                ],
+                "dnsPolicy": "ClusterFirst",
+                "restartPolicy": "Always",
+                "schedulerName": "default-scheduler",
+                "securityContext": {},
+                "terminationGracePeriodSeconds": 30
+            }
+        }
+    },
+    "status": {
+        "availableReplicas": 3,
+        "conditions": [
+            {
+                "lastTransitionTime": "2021-06-23T17:01:10Z",
+                "lastUpdateTime": "2021-06-23T17:01:18Z",
+                "message": "ReplicaSet \"nginx-6f5fdbd667\" has successfully progressed.",
+                "reason": "NewReplicaSetAvailable",
+                "status": "True",
+                "type": "Progressing"
+            },
+            {
+                "lastTransitionTime": "2021-06-23T17:59:01Z",
+                "lastUpdateTime": "2021-06-23T17:59:01Z",
+                "message": "Deployment has minimum availability.",
+                "reason": "MinimumReplicasAvailable",
+                "status": "True",
+                "type": "Available"
+            }
+        ],
+        "observedGeneration": 5,
+        "readyReplicas": 3,
+        "replicas": 4,
+        "updatedReplicas": 3
+    }
+}

pkg/cmd/edit/testdata/testcase-edit-subresource-status/test.yaml

@@ -0,0 +1,27 @@
+description: edit the status subresource
+mode: edit
+args:
+  - deployment
+  - nginx
+namespace: edit-test
+subresource: status
+expectedStdOut:
+  - deployment.apps/nginx edited
+expectedExitCode: 0
+steps:
+  - type: request
+    expectedMethod: GET
+    expectedPath: /apis/extensions/v1beta1/namespaces/edit-test/deployments/nginx/status
+    expectedInput: 0.request
+    resultingStatusCode: 200
+    resultingOutput: 0.response
+  - type: edit
+    expectedInput: 1.original
+    resultingOutput: 1.edited
+  - type: request
+    expectedMethod: PATCH
+    expectedPath: /apis/apps/v1/namespaces/edit-test/deployments/nginx/status
+    expectedContentType: application/strategic-merge-patch+json
+    expectedInput: 2.request
+    resultingStatusCode: 200
+    resultingOutput: 2.response

pkg/cmd/get/get.go

@@ -51,6 +51,7 @@ import (
 	"k8s.io/kubectl/pkg/scheme"
 	"k8s.io/kubectl/pkg/util/i18n"
 	"k8s.io/kubectl/pkg/util/interrupt"
+	"k8s.io/kubectl/pkg/util/slice"
 	"k8s.io/kubectl/pkg/util/templates"
 	utilpointer "k8s.io/utils/pointer"
 )
@@ -78,6 +79,7 @@ type GetOptions struct {
 	AllNamespaces     bool
 	Namespace         string
 	ExplicitNamespace bool
+	Subresource       string
 
 	ServerPrint bool
 
@@ -132,7 +134,10 @@ var (
 		kubectl get rc,services
 
 		# List one or more resources by their type and names
-		kubectl get rc/web service/frontend pods/web-pod-13je7`))
+		kubectl get rc/web service/frontend pods/web-pod-13je7
+
+		# List status subresource for a single pod.
+		kubectl get pod web-pod-13je7 --subresource status`))
 )
 
 const (
@@ -140,6 +145,8 @@ const (
 	useServerPrintColumns          = "server-print"
 )
 
+var supportedSubresources = []string{"status", "scale"}
+
 // NewGetOptions returns a GetOptions with default chunk size 500.
 func NewGetOptions(parent string, streams genericclioptions.IOStreams) *GetOptions {
 	return &GetOptions{
@@ -197,6 +204,7 @@ func NewCmdGet(parent string, f cmdutil.Factory, streams genericclioptions.IOStr
 	cmdutil.AddFilenameOptionFlags(cmd, &o.FilenameOptions, "identifying the resource to get from a server.")
 	cmdutil.AddChunkSizeFlag(cmd, &o.ChunkSize)
 	cmdutil.AddLabelSelectorFlagVar(cmd, &o.LabelSelector)
+	cmdutil.AddSubresourceFlags(cmd, &o.Subresource, "If specified, gets the subresource of the requested object.", supportedSubresources...)
 	return cmd
 }
 
@@ -331,6 +339,9 @@ func (o *GetOptions) Validate(cmd *cobra.Command) error {
 	if o.OutputWatchEvents && !(o.Watch || o.WatchOnly) {
 		return cmdutil.UsageErrorf(cmd, "--output-watch-events option can only be used with --watch or --watch-only")
 	}
+	if len(o.Subresource) > 0 && !slice.ContainsString(supportedSubresources, o.Subresource, nil) {
+		return fmt.Errorf("invalid subresource value: %q. Must be one of %v", o.Subresource, supportedSubresources)
+	}
 	return nil
 }
 
@@ -484,6 +495,7 @@ func (o *GetOptions) Run(f cmdutil.Factory, cmd *cobra.Command, args []string) e
 		FilenameParam(o.ExplicitNamespace, &o.FilenameOptions).
 		LabelSelectorParam(o.LabelSelector).
 		FieldSelectorParam(o.FieldSelector).
+		Subresource(o.Subresource).
 		RequestChunksOf(chunkSize).
 		ResourceTypeOrNameArgs(true, args...).
 		ContinueOnError().

pkg/cmd/get/get_test.go

@@ -242,6 +242,60 @@ foo    <unknown>
 	}
 }
 
+func TestGetObjectSubresourceStatus(t *testing.T) {
+	_, _, replicationcontrollers := cmdtesting.TestData()
+
+	tf := cmdtesting.NewTestFactory().WithNamespace("test")
+	defer tf.Cleanup()
+	codec := scheme.Codecs.LegacyCodec(scheme.Scheme.PrioritizedVersionsAllGroups()...)
+
+	tf.UnstructuredClient = &fake.RESTClient{
+		NegotiatedSerializer: resource.UnstructuredPlusDefaultContentConfig().NegotiatedSerializer,
+		Resp:                 &http.Response{StatusCode: http.StatusOK, Header: cmdtesting.DefaultHeader(), Body: cmdtesting.ObjBody(codec, &replicationcontrollers.Items[0])},
+	}
+
+	streams, _, buf, _ := genericclioptions.NewTestIOStreams()
+	cmd := NewCmdGet("kubectl", tf, streams)
+	cmd.SetOutput(buf)
+	cmd.Flags().Set("subresource", "status")
+	cmd.Run(cmd, []string{"replicationcontrollers", "rc1"})
+
+	expected := `NAME   AGE
+rc1    <unknown>
+`
+
+	if e, a := expected, buf.String(); e != a {
+		t.Errorf("expected\n%v\ngot\n%v", e, a)
+	}
+}
+
+func TestGetObjectSubresourceScale(t *testing.T) {
+	_, _, replicationcontrollers := cmdtesting.TestData()
+
+	tf := cmdtesting.NewTestFactory().WithNamespace("test")
+	defer tf.Cleanup()
+	codec := scheme.Codecs.LegacyCodec(scheme.Scheme.PrioritizedVersionsAllGroups()...)
+
+	tf.UnstructuredClient = &fake.RESTClient{
+		NegotiatedSerializer: resource.UnstructuredPlusDefaultContentConfig().NegotiatedSerializer,
+		Resp:                 &http.Response{StatusCode: http.StatusOK, Header: cmdtesting.DefaultHeader(), Body: replicationControllersScaleSubresourceTableObjBody(codec, replicationcontrollers.Items[0])},
+	}
+
+	streams, _, buf, _ := genericclioptions.NewTestIOStreams()
+	cmd := NewCmdGet("kubectl", tf, streams)
+	cmd.SetOutput(buf)
+	cmd.Flags().Set("subresource", "scale")
+	cmd.Run(cmd, []string{"replicationcontrollers", "rc1"})
+
+	expected := `NAME   DESIRED   AVAILABLE
+rc1    1         0
+`
+
+	if e, a := expected, buf.String(); e != a {
+		t.Errorf("expected\n%v\ngot\n%v", e, a)
+	}
+}
+
 func TestGetTableObjects(t *testing.T) {
 	pods, _, _ := cmdtesting.TestData()
 
@@ -2902,3 +2956,23 @@ func emptyTableObjBody(codec runtime.Codec) io.ReadCloser {
 	}
 	return cmdtesting.ObjBody(codec, table)
 }
+
+func replicationControllersScaleSubresourceTableObjBody(codec runtime.Codec, replicationControllers ...corev1.ReplicationController) io.ReadCloser {
+	table := &metav1.Table{
+		ColumnDefinitions: []metav1.TableColumnDefinition{
+			{Name: "Name", Type: "string", Description: metav1.ObjectMeta{}.SwaggerDoc()["name"]},
+			{Name: "Desired", Type: "integer", Description: autoscalingv1.ScaleSpec{}.SwaggerDoc()["replicas"]},
+			{Name: "Available", Type: "integer", Description: autoscalingv1.ScaleStatus{}.SwaggerDoc()["replicas"]},
+		},
+	}
+
+	for i := range replicationControllers {
+		b := bytes.NewBuffer(nil)
+		codec.Encode(&replicationControllers[i], b)
+		table.Rows = append(table.Rows, metav1.TableRow{
+			Object: runtime.RawExtension{Raw: b.Bytes()},
+			Cells:  []interface{}{replicationControllers[i].Name, replicationControllers[i].Spec.Replicas, replicationControllers[i].Status.Replicas},
+		})
+	}
+	return cmdtesting.ObjBody(codec, table)
+}

pkg/cmd/patch/patch.go

@@ -41,6 +41,7 @@ import (
 	"k8s.io/kubectl/pkg/scheme"
 	"k8s.io/kubectl/pkg/util"
 	"k8s.io/kubectl/pkg/util/i18n"
+	"k8s.io/kubectl/pkg/util/slice"
 	"k8s.io/kubectl/pkg/util/templates"
 )
 
@@ -56,10 +57,11 @@ type PatchOptions struct {
 	ToPrinter   func(string) (printers.ResourcePrinter, error)
 	Recorder    genericclioptions.Recorder
 
-	Local     bool
+	Local       bool
-	PatchType string
+	PatchType   string
-	Patch     string
+	Patch       string
-	PatchFile string
+	PatchFile   string
+	Subresource string
 
 	namespace                    string
 	enforceNamespace             bool
@@ -94,9 +96,14 @@ var (
 		kubectl patch pod valid-pod -p '{"spec":{"containers":[{"name":"kubernetes-serve-hostname","image":"new image"}]}}'
 
 		# Update a container's image using a JSON patch with positional arrays
-		kubectl patch pod valid-pod --type='json' -p='[{"op": "replace", "path": "/spec/containers/0/image", "value":"new image"}]'`))
+		kubectl patch pod valid-pod --type='json' -p='[{"op": "replace", "path": "/spec/containers/0/image", "value":"new image"}]'
+		
+		# Update a deployment's replicas through the scale subresource using a merge patch.
+		kubectl patch deployment nginx-deployment --subresource='scale' --type='merge' -p '{"spec":{"replicas":2}}'`))
 )
 
+var supportedSubresources = []string{"status", "scale"}
+
 func NewPatchOptions(ioStreams genericclioptions.IOStreams) *PatchOptions {
 	return &PatchOptions{
 		RecordFlags: genericclioptions.NewRecordFlags(),
@@ -133,6 +140,7 @@ func NewCmdPatch(f cmdutil.Factory, ioStreams genericclioptions.IOStreams) *cobr
 	cmdutil.AddFilenameOptionFlags(cmd, &o.FilenameOptions, "identifying the resource to update")
 	cmd.Flags().BoolVar(&o.Local, "local", o.Local, "If true, patch will operate on the content of the file, not the server-side resource.")
 	cmdutil.AddFieldManagerFlagVar(cmd, &o.fieldManager, "kubectl-patch")
+	cmdutil.AddSubresourceFlags(cmd, &o.Subresource, "If specified, patch will operate on the subresource of the requested object.", supportedSubresources...)
 
 	return cmd
 }
@@ -192,7 +200,9 @@ func (o *PatchOptions) Validate() error {
 			return fmt.Errorf("--type must be one of %v, not %q", sets.StringKeySet(patchTypes).List(), o.PatchType)
 		}
 	}
-
+	if len(o.Subresource) > 0 && !slice.ContainsString(supportedSubresources, o.Subresource, nil) {
+		return fmt.Errorf("invalid subresource value: %q. Must be one of %v", o.Subresource, supportedSubresources)
+	}
 	return nil
 }
 
@@ -224,6 +234,7 @@ func (o *PatchOptions) RunPatch() error {
 		LocalParam(o.Local).
 		NamespaceParam(o.namespace).DefaultNamespace().
 		FilenameParam(o.enforceNamespace, &o.FilenameOptions).
+		Subresource(o.Subresource).
 		ResourceTypeOrNameArgs(false, o.args...).
 		Flatten().
 		Do()
@@ -255,7 +266,8 @@ func (o *PatchOptions) RunPatch() error {
 			helper := resource.
 				NewHelper(client, mapping).
 				DryRun(o.dryRunStrategy == cmdutil.DryRunServer).
-				WithFieldManager(o.fieldManager)
+				WithFieldManager(o.fieldManager).
+				WithSubresource(o.Subresource)
 			patchedObj, err := helper.Patch(namespace, name, patchType, patchBytes, nil)
 			if err != nil {
 				return err

pkg/cmd/patch/patch_test.go

@@ -21,6 +21,8 @@ import (
 	"strings"
 	"testing"
 
+	jsonpath "github.com/exponent-io/jsonpath"
+	corev1 "k8s.io/api/core/v1"
 	"k8s.io/cli-runtime/pkg/genericclioptions"
 	"k8s.io/cli-runtime/pkg/resource"
 	"k8s.io/client-go/rest/fake"
@@ -190,3 +192,51 @@ func TestPatchObjectFromFileOutput(t *testing.T) {
 		t.Errorf("unexpected output: %s", buf.String())
 	}
 }
+
+func TestPatchSubresource(t *testing.T) {
+	pod := cmdtesting.SubresourceTestData()
+
+	tf := cmdtesting.NewTestFactory().WithNamespace("test")
+	defer tf.Cleanup()
+
+	expectedStatus := corev1.PodRunning
+
+	codec := scheme.Codecs.LegacyCodec(scheme.Scheme.PrioritizedVersionsAllGroups()...)
+
+	tf.UnstructuredClient = &fake.RESTClient{
+		NegotiatedSerializer: resource.UnstructuredPlusDefaultContentConfig().NegotiatedSerializer,
+		Client: fake.CreateHTTPClient(func(req *http.Request) (*http.Response, error) {
+			switch p, m := req.URL.Path, req.Method; {
+			case p == "/namespaces/test/pods/foo/status" && (m == "PATCH" || m == "GET"):
+				obj := pod
+
+				// ensure patched object reflects successful
+				// patch edits from the client
+				if m == "PATCH" {
+					obj.Status.Phase = expectedStatus
+				}
+				return &http.Response{StatusCode: http.StatusOK, Header: cmdtesting.DefaultHeader(), Body: cmdtesting.ObjBody(codec, obj)}, nil
+			default:
+				t.Fatalf("unexpected request: %#v\n%#v", req.URL, req)
+				return nil, nil
+			}
+		}),
+	}
+	stream, _, buf, _ := genericclioptions.NewTestIOStreams()
+
+	cmd := NewCmdPatch(tf, stream)
+	cmd.Flags().Set("namespace", "test")
+	cmd.Flags().Set("patch", `{"status":{"phase":"Running"}}`)
+	cmd.Flags().Set("output", "json")
+	cmd.Flags().Set("subresource", "status")
+	cmd.Run(cmd, []string{"pod/foo"})
+
+	decoder := jsonpath.NewDecoder(buf)
+	var actualStatus corev1.PodPhase
+	decoder.SeekTo("status", "phase")
+	decoder.Decode(&actualStatus)
+	// check the status.phase value is updated in the response
+	if actualStatus != expectedStatus {
+		t.Errorf("unexpected pod status to be set to %s got: %s", expectedStatus, actualStatus)
+	}
+}

pkg/cmd/replace/replace.go

@@ -40,6 +40,7 @@ import (
 	"k8s.io/kubectl/pkg/scheme"
 	"k8s.io/kubectl/pkg/util"
 	"k8s.io/kubectl/pkg/util/i18n"
+	"k8s.io/kubectl/pkg/util/slice"
 	"k8s.io/kubectl/pkg/util/templates"
 	"k8s.io/kubectl/pkg/validation"
 )
@@ -67,6 +68,8 @@ var (
 		kubectl replace --force -f ./pod.json`))
 )
 
+var supportedSubresources = []string{"status", "scale"}
+
 type ReplaceOptions struct {
 	PrintFlags  *genericclioptions.PrintFlags
 	RecordFlags *genericclioptions.RecordFlags
@@ -92,6 +95,8 @@ type ReplaceOptions struct {
 
 	Recorder genericclioptions.Recorder
 
+	Subresource string
+
 	genericclioptions.IOStreams
 
 	fieldManager string
@@ -132,6 +137,7 @@ func NewCmdReplace(f cmdutil.Factory, streams genericclioptions.IOStreams) *cobr
 
 	cmd.Flags().StringVar(&o.Raw, "raw", o.Raw, "Raw URI to PUT to the server.  Uses the transport specified by the kubeconfig file.")
 	cmdutil.AddFieldManagerFlagVar(cmd, &o.fieldManager, "kubectl-replace")
+	cmdutil.AddSubresourceFlags(cmd, &o.Subresource, "If specified, replace will operate on the subresource of the requested object.", supportedSubresources...)
 
 	return cmd
 }
@@ -238,6 +244,10 @@ func (o *ReplaceOptions) Validate(cmd *cobra.Command) error {
 		}
 	}
 
+	if len(o.Subresource) > 0 && !slice.ContainsString(supportedSubresources, o.Subresource, nil) {
+		return fmt.Errorf("invalid subresource value: %q. Must be one of %v", o.Subresource, supportedSubresources)
+	}
+
 	return nil
 }
 
@@ -262,6 +272,7 @@ func (o *ReplaceOptions) Run(f cmdutil.Factory) error {
 		ContinueOnError().
 		NamespaceParam(o.Namespace).DefaultNamespace().
 		FilenameParam(o.EnforceNamespace, &o.DeleteOptions.FilenameOptions).
+		Subresource(o.Subresource).
 		Flatten().
 		Do()
 	if err := r.Err(); err != nil {
@@ -295,6 +306,7 @@ func (o *ReplaceOptions) Run(f cmdutil.Factory) error {
 			NewHelper(info.Client, info.Mapping).
 			DryRun(o.DryRunStrategy == cmdutil.DryRunServer).
 			WithFieldManager(o.fieldManager).
+			WithSubresource(o.Subresource).
 			Replace(info.Namespace, info.Name, true, info.Object)
 		if err != nil {
 			return cmdutil.AddSourceToErr("replacing", info.Source, err)
@@ -330,6 +342,7 @@ func (o *ReplaceOptions) forceReplace() error {
 		NamespaceParam(o.Namespace).DefaultNamespace().
 		ResourceTypeOrNameArgs(false, o.BuilderArgs...).RequireObject(false).
 		FilenameParam(o.EnforceNamespace, &o.DeleteOptions.FilenameOptions).
+		Subresource(o.Subresource).
 		Flatten()
 	if stdinInUse {
 		b = b.StdinInUse()
@@ -369,6 +382,7 @@ func (o *ReplaceOptions) forceReplace() error {
 		ContinueOnError().
 		NamespaceParam(o.Namespace).DefaultNamespace().
 		FilenameParam(o.EnforceNamespace, &o.DeleteOptions.FilenameOptions).
+		Subresource(o.Subresource).
 		Flatten()
 	if stdinInUse {
 		b = b.StdinInUse()

pkg/cmd/testing/util.go

@@ -150,6 +150,22 @@ func EmptyTestData() (*corev1.PodList, *corev1.ServiceList, *corev1.ReplicationC
 	return pods, svc, rc
 }
 
+func SubresourceTestData() *corev1.Pod {
+	return &corev1.Pod{
+		ObjectMeta: metav1.ObjectMeta{Name: "foo", Namespace: "test", ResourceVersion: "10"},
+		Spec: corev1.PodSpec{
+			RestartPolicy:                 corev1.RestartPolicyAlways,
+			DNSPolicy:                     corev1.DNSClusterFirst,
+			TerminationGracePeriodSeconds: &grace,
+			SecurityContext:               &corev1.PodSecurityContext{},
+			EnableServiceLinks:            &enableServiceLinks,
+		},
+		Status: corev1.PodStatus{
+			Phase: corev1.PodPending,
+		},
+	}
+}
+
 func GenResponseWithJsonEncodedBody(bodyStruct interface{}) (*http.Response, error) {
 	jsonBytes, err := json.Marshal(bodyStruct)
 	if err != nil {

pkg/cmd/util/editor/editoptions.go

@@ -51,8 +51,11 @@ import (
 	"k8s.io/kubectl/pkg/cmd/util/editor/crlf"
 	"k8s.io/kubectl/pkg/scheme"
 	"k8s.io/kubectl/pkg/util"
+	"k8s.io/kubectl/pkg/util/slice"
 )
 
+var SupportedSubresources = []string{"status"}
+
 // EditOptions contains all the options for running edit cli command.
 type EditOptions struct {
 	resource.FilenameOptions
@@ -84,6 +87,8 @@ type EditOptions struct {
 	updatedResultGetter func(data []byte) *resource.Result
 
 	FieldManager string
+
+	Subresource string
 }
 
 // NewEditOptions returns an initialized EditOptions instance
@@ -184,6 +189,7 @@ func (o *EditOptions) Complete(f cmdutil.Factory, args []string, cmd *cobra.Comm
 	}
 	r := b.NamespaceParam(cmdNamespace).DefaultNamespace().
 		FilenameParam(enforceNamespace, &o.FilenameOptions).
+		Subresource(o.Subresource).
 		ContinueOnError().
 		Flatten().
 		Do()
@@ -198,6 +204,7 @@ func (o *EditOptions) Complete(f cmdutil.Factory, args []string, cmd *cobra.Comm
 		return f.NewBuilder().
 			Unstructured().
 			Stream(bytes.NewReader(data), "edited-file").
+			Subresource(o.Subresource).
 			ContinueOnError().
 			Flatten().
 			Do()
@@ -216,6 +223,9 @@ func (o *EditOptions) Complete(f cmdutil.Factory, args []string, cmd *cobra.Comm
 
 // Validate checks the EditOptions to see if there is sufficient information to run the command.
 func (o *EditOptions) Validate() error {
+	if len(o.Subresource) > 0 && !slice.ContainsString(SupportedSubresources, o.Subresource, nil) {
+		return fmt.Errorf("invalid subresource value: %q. Must be one of %v", o.Subresource, SupportedSubresources)
+	}
 	return nil
 }
 
@@ -561,7 +571,7 @@ func (o *EditOptions) annotationPatch(update *resource.Info) error {
 	if err != nil {
 		return err
 	}
-	helper := resource.NewHelper(client, mapping).WithFieldManager(o.FieldManager)
+	helper := resource.NewHelper(client, mapping).WithFieldManager(o.FieldManager).WithSubresource(o.Subresource)
 	_, err = helper.Patch(o.CmdNamespace, update.Name, patchType, patch, nil)
 	if err != nil {
 		return err
@@ -699,7 +709,7 @@ func (o *EditOptions) visitToPatch(originalInfos []*resource.Info, patchVisitor
 		}
 
 		patched, err := resource.NewHelper(info.Client, info.Mapping).
-			WithFieldManager(o.FieldManager).
+			WithFieldManager(o.FieldManager).WithSubresource(o.Subresource).
 			Patch(info.Namespace, info.Name, patchType, patch, nil)
 		if err != nil {
 			fmt.Fprintln(o.ErrOut, results.addError(err, info))

pkg/cmd/util/helpers.go

@@ -470,6 +470,10 @@ func AddLabelSelectorFlagVar(cmd *cobra.Command, p *string) {
 	cmd.Flags().StringVarP(p, "selector", "l", *p, "Selector (label query) to filter on, supports '=', '==', and '!='.(e.g. -l key1=value1,key2=value2). Matching objects must satisfy all of the specified label constraints.")
 }
 
+func AddSubresourceFlags(cmd *cobra.Command, subresource *string, usage string, allowedSubresources ...string) {
+	cmd.Flags().StringVar(subresource, "subresource", "", fmt.Sprintf("%s Must be one of %v. This flag is alpha and may change in the future.", usage, allowedSubresources))
+}
+
 type ValidateOptions struct {
 	EnableValidation bool
 }