Merge pull request #12511 from feihujiang/kubectlGetAcceptFileNameParam

Kubectl get command accepts a filename param

contrib/completions/bash/kubectl

@@ -230,6 +230,12 @@ _kubectl_get()
     flags_completion=()
 
     flags+=("--all-namespaces")
+    flags+=("--filename=")
+    flags_with_completion+=("--filename")
+    flags_completion+=("__handle_filename_extension_flag json|yaml|yml")
+    two_word_flags+=("-f")
+    flags_with_completion+=("-f")
+    flags_completion+=("__handle_filename_extension_flag json|yaml|yml")
     flags+=("--help")
     flags+=("-h")
     flags+=("--label-columns=")

docs/man/man1/kubectl-get.1

@@ -31,6 +31,10 @@ of the \-\-template flag, you can filter the attributes of the fetched resource(
 \fB\-\-all\-namespaces\fP=false
     If present, list the requested object(s) across all namespaces. Namespace in current context is ignored even if specified with \-\-namespace.
 
+.PP
+\fB\-f\fP, \fB\-\-filename\fP=[]
+    Filename, directory, or URL to a file identifying the resource to get from a server.
+
 .PP
 \fB\-h\fP, \fB\-\-help\fP=false
     help for get
@@ -188,6 +192,9 @@ $ kubectl get replicationcontroller web
 # List a single pod in JSON output format.
 $ kubectl get \-o json pod web\-pod\-13je7
 
+# List a pod identified by type and name specified in "pod.yaml" in JSON output format.
+$ kubectl get \-f pod.yaml \-o json
+
 # Return only the phase value of the specified pod.
 $ kubectl get \-o template web\-pod\-13je7 \-\-template={{.status.phase}} \-\-api\-version=v1
 

docs/user-guide/kubectl/kubectl_get.md

@@ -67,6 +67,9 @@ $ kubectl get replicationcontroller web
 # List a single pod in JSON output format.
 $ kubectl get -o json pod web-pod-13je7
 
+# List a pod identified by type and name specified in "pod.yaml" in JSON output format.
+$ kubectl get -f pod.yaml -o json
+
 # Return only the phase value of the specified pod.
 $ kubectl get -o template web-pod-13je7 --template={{.status.phase}} --api-version=v1
 
@@ -81,6 +84,7 @@ $ kubectl get rc/web service/frontend pods/web-pod-13je7
 
 ```
       --all-namespaces[=false]: If present, list the requested object(s) across all namespaces. Namespace in current context is ignored even if specified with --namespace.
+  -f, --filename=[]: Filename, directory, or URL to a file identifying the resource to get from a server.
   -h, --help[=false]: help for get
   -L, --label-columns=[]: Accepts a comma separated list of labels that are going to be presented as columns. Names are case-sensitive. You can also use multiple flag statements like -L label1 -L label2...
       --no-headers[=false]: When using the default output, don't print headers.
@@ -126,7 +130,7 @@ $ kubectl get rc/web service/frontend pods/web-pod-13je7
 
 * [kubectl](kubectl.md)	 - kubectl controls the Kubernetes cluster manager
 
-###### Auto generated by spf13/cobra at 2015-08-12 23:41:01.301023165 +0000 UTC
+###### Auto generated by spf13/cobra at 2015-08-13 06:12:05.386038784 +0000 UTC
 
 <!-- BEGIN MUNGE: GENERATED_ANALYTICS -->
 [![Analytics](https://kubernetes-site.appspot.com/UA-36037335-10/GitHub/docs/user-guide/kubectl/kubectl_get.md?pixel)]()

pkg/kubectl/cmd/get.go

@@ -20,12 +20,11 @@ import (
 	"fmt"
 	"io"
 
+	"github.com/spf13/cobra"
 	"k8s.io/kubernetes/pkg/kubectl"
 	cmdutil "k8s.io/kubernetes/pkg/kubectl/cmd/util"
 	"k8s.io/kubernetes/pkg/kubectl/resource"
 	"k8s.io/kubernetes/pkg/watch"
-
-	"github.com/spf13/cobra"
 )
 
 const (
@@ -50,6 +49,9 @@ $ kubectl get replicationcontroller web
 # List a single pod in JSON output format.
 $ kubectl get -o json pod web-pod-13je7
 
+# List a pod identified by type and name specified in "pod.yaml" in JSON output format.
+$ kubectl get -f pod.yaml -o json
+
 # Return only the phase value of the specified pod.
 $ kubectl get -o template web-pod-13je7 --template={{.status.phase}} --api-version=v1
 
@@ -83,6 +85,8 @@ func NewCmdGet(f *cmdutil.Factory, out io.Writer) *cobra.Command {
 	cmd.Flags().Bool("watch-only", false, "Watch for changes to the requested object(s), without listing/getting first.")
 	cmd.Flags().Bool("all-namespaces", false, "If present, list the requested object(s) across all namespaces. Namespace in current context is ignored even if specified with --namespace.")
 	cmd.Flags().StringSliceP("label-columns", "L", []string{}, "Accepts a comma separated list of labels that are going to be presented as columns. Names are case-sensitive. You can also use multiple flag statements like -L label1 -L label2...")
+	usage := "Filename, directory, or URL to a file identifying the resource to get from a server."
+	kubectl.AddJsonFilenameFlag(cmd, usage)
 	return cmd
 }
 
@@ -93,12 +97,14 @@ func RunGet(f *cmdutil.Factory, out io.Writer, cmd *cobra.Command, args []string
 	allNamespaces := cmdutil.GetFlagBool(cmd, "all-namespaces")
 	mapper, typer := f.Object()
 
-	cmdNamespace, _, err := f.DefaultNamespace()
+	cmdNamespace, enforceNamespace, err := f.DefaultNamespace()
 	if err != nil {
 		return err
 	}
 
-	if len(args) == 0 {
+	filenames := cmdutil.GetFlagStringSlice(cmd, "filename")
+
+	if len(args) == 0 && len(filenames) == 0 {
 		fmt.Fprint(out, "You must specify the type of resource to get. ", valid_resources, `   * componentstatuses (aka 'cs')
    * endpoints (aka 'ep')
 `)
@@ -110,19 +116,24 @@ func RunGet(f *cmdutil.Factory, out io.Writer, cmd *cobra.Command, args []string
 	if isWatch || isWatchOnly {
 		r := resource.NewBuilder(mapper, typer, f.ClientMapperForCommand()).
 			NamespaceParam(cmdNamespace).DefaultNamespace().AllNamespaces(allNamespaces).
+			FilenameParam(enforceNamespace, filenames...).
 			SelectorParam(selector).
 			ResourceTypeOrNameArgs(true, args...).
 			SingleResourceType().
+			Latest().
 			Do()
 		if err != nil {
 			return err
 		}
-
+		infos, err := r.Infos()
-		mapping, err := r.ResourceMapping()
 		if err != nil {
 			return err
 		}
-
+		if len(infos) != 1 {
+			return fmt.Errorf("watch is only supported on a single resource - %d resources were found", len(infos))
+		}
+		info := infos[0]
+		mapping := info.ResourceMapping()
 		printer, err := f.PrinterForMapping(cmd, mapping, allNamespaces)
 		if err != nil {
 			return err
@@ -132,7 +143,6 @@ func RunGet(f *cmdutil.Factory, out io.Writer, cmd *cobra.Command, args []string
 		if err != nil {
 			return err
 		}
-
 		rv, err := mapping.MetadataAccessor.ResourceVersion(obj)
 		if err != nil {
 			return err
@@ -159,6 +169,7 @@ func RunGet(f *cmdutil.Factory, out io.Writer, cmd *cobra.Command, args []string
 
 	b := resource.NewBuilder(mapper, typer, f.ClientMapperForCommand()).
 		NamespaceParam(cmdNamespace).DefaultNamespace().AllNamespaces(allNamespaces).
+		FilenameParam(enforceNamespace, filenames...).
 		SelectorParam(selector).
 		ResourceTypeOrNameArgs(true, args...).
 		ContinueOnError().

pkg/kubectl/cmd/get_test.go

@@ -275,6 +275,33 @@ func TestGetObjects(t *testing.T) {
 	}
 }
 
+func TestGetObjectsIdentifiedByFile(t *testing.T) {
+	pods, _, _ := testData()
+
+	f, tf, codec := NewAPIFactory()
+	tf.Printer = &testPrinter{}
+	tf.Client = &client.FakeRESTClient{
+		Codec: codec,
+		Resp:  &http.Response{StatusCode: 200, Body: objBody(codec, &pods.Items[0])},
+	}
+	tf.Namespace = "test"
+	buf := bytes.NewBuffer([]byte{})
+
+	cmd := NewCmdGet(f, buf)
+	cmd.SetOutput(buf)
+	cmd.Flags().Set("filename", "../../../examples/cassandra/cassandra.yaml")
+	cmd.Run(cmd, []string{})
+
+	expected := []runtime.Object{&pods.Items[0]}
+	actual := tf.Printer.(*testPrinter).Objects
+	if !reflect.DeepEqual(expected, actual) {
+		t.Errorf("unexpected object: %#v", actual)
+	}
+	if len(buf.String()) == 0 {
+		t.Errorf("unexpected empty output")
+	}
+}
+
 func TestGetListObjects(t *testing.T) {
 	pods, _, _ := testData()
 
@@ -635,6 +662,45 @@ func TestWatchResource(t *testing.T) {
 	}
 }
 
+func TestWatchResourceIdentifiedByFile(t *testing.T) {
+	pods, events := watchTestData()
+
+	f, tf, codec := NewAPIFactory()
+	tf.Printer = &testPrinter{}
+	tf.Client = &client.FakeRESTClient{
+		Codec: codec,
+		Client: client.HTTPClientFunc(func(req *http.Request) (*http.Response, error) {
+			switch req.URL.Path {
+			case "/namespaces/test/pods/cassandra":
+				return &http.Response{StatusCode: 200, Body: objBody(codec, &pods[0])}, nil
+			case "/watch/namespaces/test/pods/cassandra":
+				return &http.Response{StatusCode: 200, Body: watchBody(codec, events)}, nil
+			default:
+				t.Fatalf("unexpected request: %#v\n%#v", req.URL, req)
+				return nil, nil
+			}
+		}),
+	}
+	tf.Namespace = "test"
+	buf := bytes.NewBuffer([]byte{})
+	cmd := NewCmdGet(f, buf)
+	cmd.SetOutput(buf)
+
+	cmd.Flags().Set("watch", "true")
+	cmd.Flags().Set("filename", "../../../examples/cassandra/cassandra.yaml")
+	cmd.Run(cmd, []string{})
+
+	expected := []runtime.Object{&pods[0], events[0].Object, events[1].Object}
+	actual := tf.Printer.(*testPrinter).Objects
+	if !reflect.DeepEqual(expected, actual) {
+		t.Errorf("expected object: %#v unexpected object: %#v", expected, actual)
+	}
+
+	if len(buf.String()) == 0 {
+		t.Errorf("unexpected empty output")
+	}
+}
+
 func TestWatchOnlyResource(t *testing.T) {
 	pods, events := watchTestData()