Implemented both the dry run and local flags.

Added test cases to show that both flags are operating as intended.
Removed the print statement "running in local mode" as in PR#35112

The previous attempt at the PR (PR#35050) was reverted for causeing a flake.
I believe that setting the deployments terminationGracePeriodSeconds to 0 should
take care of it. I ran hack/make-rules/test-cmd.sh 50 times in a row without encountering
the flake

hack/make-rules/test-cmd.sh

@@ -2181,33 +2181,37 @@ __EOF__
   ## Set resource limits/request of a deployment
   # Pre-condition: no deployment exists
   kube::test::get_object_assert deployment "{{range.items}}{{$id_field}}:{{end}}" ''
+  # Set resources of a local file without talking to the server 
+  kubectl set resources -f hack/testdata/deployment-multicontainer-resources.yaml -c=perl --limits=cpu=300m --requests=cpu=300m --local -o yaml "${kube_flags[@]}"
+  ! kubectl set resources -f hack/testdata/deployment-multicontainer-resources.yaml -c=perl --limits=cpu=300m --requests=cpu=300m --dry-run -o yaml "${kube_flags[@]}"
   # Create a deployment
-  kubectl create -f hack/testdata/deployment-multicontainer.yaml "${kube_flags[@]}"
+  kubectl create -f hack/testdata/deployment-multicontainer-resources.yaml "${kube_flags[@]}"
-  kube::test::get_object_assert deployment "{{range.items}}{{$id_field}}:{{end}}" 'nginx-deployment:'
+  kube::test::get_object_assert deployment "{{range.items}}{{$id_field}}:{{end}}" 'nginx-deployment-resources:'
   kube::test::get_object_assert deployment "{{range.items}}{{$deployment_image_field}}:{{end}}" "${IMAGE_DEPLOYMENT_R1}:"
   kube::test::get_object_assert deployment "{{range.items}}{{$deployment_second_image_field}}:{{end}}" "${IMAGE_PERL}:"
   # Set the deployment's cpu limits
-  kubectl set resources deployment nginx-deployment --limits=cpu=100m "${kube_flags[@]}"
+  kubectl set resources deployment nginx-deployment-resources --limits=cpu=100m "${kube_flags[@]}"
   kube::test::get_object_assert deployment "{{range.items}}{{(index .spec.template.spec.containers 0).resources.limits.cpu}}:{{end}}" "100m:"
   kube::test::get_object_assert deployment "{{range.items}}{{(index .spec.template.spec.containers 1).resources.limits.cpu}}:{{end}}" "100m:"
   # Set a non-existing container should fail
-  ! kubectl set resources deployment nginx-deployment -c=redis --limits=cpu=100m
+  ! kubectl set resources deployment nginx-deployment-resources -c=redis --limits=cpu=100m
   # Set the limit of a specific container in deployment
-  kubectl set resources deployment nginx-deployment -c=nginx --limits=cpu=200m "${kube_flags[@]}"
+  kubectl set resources deployment nginx-deployment-resources -c=nginx --limits=cpu=200m "${kube_flags[@]}"
   kube::test::get_object_assert deployment "{{range.items}}{{(index .spec.template.spec.containers 0).resources.limits.cpu}}:{{end}}" "200m:"
   kube::test::get_object_assert deployment "{{range.items}}{{(index .spec.template.spec.containers 1).resources.limits.cpu}}:{{end}}" "100m:"
   # Set limits/requests of a deployment specified by a file
-  kubectl set resources -f hack/testdata/deployment-multicontainer.yaml -c=perl --limits=cpu=300m --requests=cpu=300m "${kube_flags[@]}"
+  kubectl set resources -f hack/testdata/deployment-multicontainer-resources.yaml -c=perl --limits=cpu=300m --requests=cpu=300m "${kube_flags[@]}"
   kube::test::get_object_assert deployment "{{range.items}}{{(index .spec.template.spec.containers 0).resources.limits.cpu}}:{{end}}" "200m:"
   kube::test::get_object_assert deployment "{{range.items}}{{(index .spec.template.spec.containers 1).resources.limits.cpu}}:{{end}}" "300m:"
   kube::test::get_object_assert deployment "{{range.items}}{{(index .spec.template.spec.containers 1).resources.requests.cpu}}:{{end}}" "300m:"
-  # Set limits on a local file without talking to the server
+  # Show dry-run works on running deployments 
-  kubectl set resources deployment -f hack/testdata/deployment-multicontainer.yaml -c=perl --limits=cpu=300m --requests=cpu=300m --dry-run -o yaml "${kube_flags[@]}"
+  kubectl set resources deployment nginx-deployment-resources -c=perl --limits=cpu=400m --requests=cpu=400m --dry-run -o yaml "${kube_flags[@]}"
+  ! kubectl set resources deployment nginx-deployment-resources -c=perl --limits=cpu=400m --requests=cpu=400m --local -o yaml "${kube_flags[@]}"
   kube::test::get_object_assert deployment "{{range.items}}{{(index .spec.template.spec.containers 0).resources.limits.cpu}}:{{end}}" "200m:"
   kube::test::get_object_assert deployment "{{range.items}}{{(index .spec.template.spec.containers 1).resources.limits.cpu}}:{{end}}" "300m:"
   kube::test::get_object_assert deployment "{{range.items}}{{(index .spec.template.spec.containers 1).resources.requests.cpu}}:{{end}}" "300m:"
   # Clean up
-  kubectl delete deployment nginx-deployment "${kube_flags[@]}"
+  kubectl delete deployment nginx-deployment-resources "${kube_flags[@]}"
 
 
   ######################

hack/testdata/deployment-multicontainer-resources.yaml

@@ -0,0 +1,24 @@
+apiVersion: extensions/v1beta1
+kind: Deployment
+metadata:
+  name: nginx-deployment-resources
+  labels:
+    name: nginx-deployment-resources
+spec:
+  replicas: 3
+  selector:
+    matchLabels:
+      name: nginx
+  template:
+    metadata:
+      labels:
+        name: nginx
+    spec:
+      containers:
+      - name: nginx
+        image: gcr.io/google-containers/nginx:test-cmd
+        ports:
+        - containerPort: 80
+      - name: perl
+        image: gcr.io/google-containers/perl
+      terminationGracePeriodSeconds: 0

pkg/kubectl/cmd/set/set_resources.go

@@ -52,7 +52,7 @@ var (
 		kubectl set resources deployment nginx --limits=cpu=0,memory=0 --requests=cpu=0,memory=0
 
 		# Print the result (in yaml format) of updating nginx container limits from a local, without hitting the server
-		kubectl set resources -f path/to/file.yaml --limits=cpu=200m,memory=512Mi --dry-run -o yaml`)
+		kubectl set resources -f path/to/file.yaml --limits=cpu=200m,memory=512Mi --local -o yaml`)
 )
 
 // ResourcesOptions is the start of the data required to perform the operation. As new fields are added, add them here instead of
@@ -72,6 +72,7 @@ type ResourcesOptions struct {
 	All               bool
 	Record            bool
 	ChangeCause       string
+	Local             bool
 	Cmd               *cobra.Command
 
 	Limits               string
@@ -114,6 +115,7 @@ func NewCmdResources(f cmdutil.Factory, out io.Writer, errOut io.Writer) *cobra.
 	cmd.Flags().BoolVar(&options.All, "all", false, "select all resources in the namespace of the specified resource types")
 	cmd.Flags().StringVarP(&options.Selector, "selector", "l", "", "Selector (label query) to filter on")
 	cmd.Flags().StringVarP(&options.ContainerSelector, "containers", "c", "*", "The names of containers in the selected pod templates to change, all containers are selected by default - may use wildcards")
+	cmd.Flags().BoolVar(&options.Local, "local", false, "If true, set resources will NOT contact api-server but run locally.")
 	cmdutil.AddDryRunFlag(cmd)
 	cmdutil.AddRecordFlag(cmd)
 	cmd.Flags().StringVar(&options.Limits, "limits", options.Limits, "The resource requirement requests for this container.  For example, 'cpu=100m,memory=256Mi'.  Note that server side components may assign requests depending on the server configuration, such as limit ranges.")
@@ -142,7 +144,7 @@ func (o *ResourcesOptions) Complete(f cmdutil.Factory, cmd *cobra.Command, args
 		//FilenameParam(enforceNamespace, o.Filenames...).
 		FilenameParam(enforceNamespace, &o.FilenameOptions).
 		Flatten()
-	if !cmdutil.GetDryRunFlag(cmd) {
+	if !o.Local {
 		builder = builder.
 			SelectorParam(o.Selector).
 			ResourceTypeOrNameArgs(o.All, args...).
@@ -214,8 +216,7 @@ func (o *ResourcesOptions) Run() error {
 			continue
 		}
 
-		if cmdutil.GetDryRunFlag(o.Cmd) {
+		if o.Local || cmdutil.GetDryRunFlag(o.Cmd) {
-			fmt.Fprintln(o.Err, "info: running in local mode...")
 			return o.PrintObject(o.Cmd, o.Mapper, info.Object, o.Out)
 		}