Merge pull request #86810 from bart0sh/PR0087-kubeadm-output-images

kubeadm config images list: implement structured output

cmd/kubeadm/app/apis/output/register.go

@@ -47,6 +47,7 @@ func Resource(resource string) schema.GroupResource {
 func addKnownTypes(scheme *runtime.Scheme) error {
 	scheme.AddKnownTypes(SchemeGroupVersion,
 		&BootstrapToken{},
+		&Images{},
 	)
 	return nil
 }

cmd/kubeadm/app/apis/output/types.go

@@ -31,3 +31,12 @@ type BootstrapToken struct {
 
 	kubeadmapiv1beta2.BootstrapToken
 }
+
+// +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object
+
+// Images represents information for the output produced by 'kubeadm config images list'
+type Images struct {
+	metav1.TypeMeta
+
+	Images []string
+}

cmd/kubeadm/app/apis/output/v1alpha1/register.go

@@ -59,6 +59,7 @@ func Resource(resource string) schema.GroupResource {
 func addKnownTypes(scheme *runtime.Scheme) error {
 	scheme.AddKnownTypes(SchemeGroupVersion,
 		&BootstrapToken{},
+		&Images{},
 	)
 	metav1.AddToGroupVersion(scheme, SchemeGroupVersion)
 	return nil

cmd/kubeadm/app/apis/output/v1alpha1/types.go

@@ -31,3 +31,12 @@ type BootstrapToken struct {
 
 	kubeadmapiv1beta2.BootstrapToken
 }
+
+// +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object
+
+// Images represents information for the output produced by 'kubeadm config images list'
+type Images struct {
+	metav1.TypeMeta `json:",inline"`
+
+	Images []string `json:"images"`
+}

cmd/kubeadm/app/apis/output/v1alpha1/zz_generated.conversion.go

@@ -21,6 +21,8 @@ limitations under the License.
 package v1alpha1
 
 import (
+	unsafe "unsafe"
+
 	conversion "k8s.io/apimachinery/pkg/conversion"
 	runtime "k8s.io/apimachinery/pkg/runtime"
 	output "k8s.io/kubernetes/cmd/kubeadm/app/apis/output"
@@ -43,6 +45,16 @@ func RegisterConversions(s *runtime.Scheme) error {
 	}); err != nil {
 		return err
 	}
+	if err := s.AddGeneratedConversionFunc((*Images)(nil), (*output.Images)(nil), func(a, b interface{}, scope conversion.Scope) error {
+		return Convert_v1alpha1_Images_To_output_Images(a.(*Images), b.(*output.Images), scope)
+	}); err != nil {
+		return err
+	}
+	if err := s.AddGeneratedConversionFunc((*output.Images)(nil), (*Images)(nil), func(a, b interface{}, scope conversion.Scope) error {
+		return Convert_output_Images_To_v1alpha1_Images(a.(*output.Images), b.(*Images), scope)
+	}); err != nil {
+		return err
+	}
 	return nil
 }
 
@@ -65,3 +77,23 @@ func autoConvert_output_BootstrapToken_To_v1alpha1_BootstrapToken(in *output.Boo
 func Convert_output_BootstrapToken_To_v1alpha1_BootstrapToken(in *output.BootstrapToken, out *BootstrapToken, s conversion.Scope) error {
 	return autoConvert_output_BootstrapToken_To_v1alpha1_BootstrapToken(in, out, s)
 }
+
+func autoConvert_v1alpha1_Images_To_output_Images(in *Images, out *output.Images, s conversion.Scope) error {
+	out.Images = *(*[]string)(unsafe.Pointer(&in.Images))
+	return nil
+}
+
+// Convert_v1alpha1_Images_To_output_Images is an autogenerated conversion function.
+func Convert_v1alpha1_Images_To_output_Images(in *Images, out *output.Images, s conversion.Scope) error {
+	return autoConvert_v1alpha1_Images_To_output_Images(in, out, s)
+}
+
+func autoConvert_output_Images_To_v1alpha1_Images(in *output.Images, out *Images, s conversion.Scope) error {
+	out.Images = *(*[]string)(unsafe.Pointer(&in.Images))
+	return nil
+}
+
+// Convert_output_Images_To_v1alpha1_Images is an autogenerated conversion function.
+func Convert_output_Images_To_v1alpha1_Images(in *output.Images, out *Images, s conversion.Scope) error {
+	return autoConvert_output_Images_To_v1alpha1_Images(in, out, s)
+}

cmd/kubeadm/app/apis/output/v1alpha1/zz_generated.deepcopy.go

@@ -49,3 +49,33 @@ func (in *BootstrapToken) DeepCopyObject() runtime.Object {
 	}
 	return nil
 }
+
+// DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
+func (in *Images) DeepCopyInto(out *Images) {
+	*out = *in
+	out.TypeMeta = in.TypeMeta
+	if in.Images != nil {
+		in, out := &in.Images, &out.Images
+		*out = make([]string, len(*in))
+		copy(*out, *in)
+	}
+	return
+}
+
+// DeepCopy is an autogenerated deepcopy function, copying the receiver, creating a new Images.
+func (in *Images) DeepCopy() *Images {
+	if in == nil {
+		return nil
+	}
+	out := new(Images)
+	in.DeepCopyInto(out)
+	return out
+}
+
+// DeepCopyObject is an autogenerated deepcopy function, copying the receiver, creating a new runtime.Object.
+func (in *Images) DeepCopyObject() runtime.Object {
+	if c := in.DeepCopy(); c != nil {
+		return c
+	}
+	return nil
+}

cmd/kubeadm/app/apis/output/zz_generated.deepcopy.go

@@ -49,3 +49,33 @@ func (in *BootstrapToken) DeepCopyObject() runtime.Object {
 	}
 	return nil
 }
+
+// DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
+func (in *Images) DeepCopyInto(out *Images) {
+	*out = *in
+	out.TypeMeta = in.TypeMeta
+	if in.Images != nil {
+		in, out := &in.Images, &out.Images
+		*out = make([]string, len(*in))
+		copy(*out, *in)
+	}
+	return
+}
+
+// DeepCopy is an autogenerated deepcopy function, copying the receiver, creating a new Images.
+func (in *Images) DeepCopy() *Images {
+	if in == nil {
+		return nil
+	}
+	out := new(Images)
+	in.DeepCopyInto(out)
+	return out
+}
+
+// DeepCopyObject is an autogenerated deepcopy function, copying the receiver, creating a new runtime.Object.
+func (in *Images) DeepCopyObject() runtime.Object {
+	if c := in.DeepCopy(); c != nil {
+		return c
+	}
+	return nil
+}

cmd/kubeadm/app/cmd/config.go

@@ -23,6 +23,7 @@ import (
 	"io"
 	"io/ioutil"
 	"sort"
+	"strings"
 
 	"github.com/lithammer/dedent"
 	"github.com/pkg/errors"
@@ -31,10 +32,14 @@ import (
 	"k8s.io/klog"
 
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/cli-runtime/pkg/genericclioptions"
 	clientset "k8s.io/client-go/kubernetes"
 	kubeadmapi "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
 	kubeadmscheme "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/scheme"
 	kubeadmapiv1beta2 "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/v1beta2"
+	outputapischeme "k8s.io/kubernetes/cmd/kubeadm/app/apis/output/scheme"
+	outputapiv1alpha1 "k8s.io/kubernetes/cmd/kubeadm/app/apis/output/v1alpha1"
 	"k8s.io/kubernetes/cmd/kubeadm/app/cmd/options"
 	phaseutil "k8s.io/kubernetes/cmd/kubeadm/app/cmd/phases"
 	cmdutil "k8s.io/kubernetes/cmd/kubeadm/app/cmd/util"
@@ -45,6 +50,7 @@ import (
 	"k8s.io/kubernetes/cmd/kubeadm/app/phases/uploadconfig"
 	configutil "k8s.io/kubernetes/cmd/kubeadm/app/util/config"
 	kubeconfigutil "k8s.io/kubernetes/cmd/kubeadm/app/util/kubeconfig"
+	"k8s.io/kubernetes/cmd/kubeadm/app/util/output"
 	utilruntime "k8s.io/kubernetes/cmd/kubeadm/app/util/runtime"
 	utilsexec "k8s.io/utils/exec"
 )
@@ -527,6 +533,8 @@ func NewCmdConfigImagesList(out io.Writer, mockK8sVersion *string) *cobra.Comman
 		externalcfg.KubernetesVersion = *mockK8sVersion
 	}
 
+	outputFlags := output.NewOutputFlags(&imageTextPrintFlags{}).WithTypeSetter(outputapischeme.Scheme).WithDefaultOutput(output.TextOutput)
+
 	cmd := &cobra.Command{
 		Use:   "list",
 		Short: "Print a list of images kubeadm will use. The configuration file is used in case any images or image repositories are customized",
@@ -536,14 +544,20 @@ func NewCmdConfigImagesList(out io.Writer, mockK8sVersion *string) *cobra.Comman
 				return err
 			}
 
+			printer, err := outputFlags.ToPrinter()
+			if err != nil {
+				return err
+			}
+
 			imagesList, err := NewImagesList(cfgPath, externalcfg)
 			if err != nil {
 				return err
 			}
 
-			return imagesList.Run(out)
+			return imagesList.Run(out, printer)
 		},
 	}
+	outputFlags.AddFlags(cmd)
 	AddImagesCommonConfigFlags(cmd.PersistentFlags(), externalcfg, &cfgPath, &featureGatesString)
 	return cmd
 }
@@ -572,11 +586,39 @@ type ImagesList struct {
 	cfg *kubeadmapi.InitConfiguration
 }
 
+// imageTextPrinter prints image info in a text form
+type imageTextPrinter struct {
+	output.TextPrinter
+}
+
+// PrintObj is an implementation of ResourcePrinter.PrintObj for plain text output
+func (itp *imageTextPrinter) PrintObj(obj runtime.Object, writer io.Writer) error {
+	var err error
+	if imgs, ok := obj.(*outputapiv1alpha1.Images); ok {
+		_, err = fmt.Fprintln(writer, strings.Join(imgs.Images, "\n"))
+	} else {
+		err = errors.New("unexpected object type")
+	}
+	return err
+}
+
+// imageTextPrintFlags provides flags necessary for printing image in a text form.
+type imageTextPrintFlags struct{}
+
+// ToPrinter returns kubeadm printer for the text output format
+func (ipf *imageTextPrintFlags) ToPrinter(outputFormat string) (output.Printer, error) {
+	if outputFormat == output.TextOutput {
+		return &imageTextPrinter{}, nil
+	}
+	return nil, genericclioptions.NoCompatiblePrinterError{OutputFormat: &outputFormat, AllowedFormats: []string{output.TextOutput}}
+}
+
 // Run runs the images command and writes the result to the io.Writer passed in
-func (i *ImagesList) Run(out io.Writer) error {
+func (i *ImagesList) Run(out io.Writer, printer output.Printer) error {
 	imgs := images.GetControlPlaneImages(&i.cfg.ClusterConfiguration)
-	for _, img := range imgs {
-		fmt.Fprintln(out, img)
+
+	if err := printer.PrintObj(&outputapiv1alpha1.Images{Images: imgs}, out); err != nil {
+		return errors.Wrap(err, "unable to print images")
 	}
 
 	return nil

cmd/kubeadm/app/cmd/config_test.go

@@ -31,9 +31,11 @@ import (
 	"github.com/lithammer/dedent"
 	"github.com/spf13/cobra"
 	kubeadmapiv1beta2 "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/v1beta2"
+	outputapischeme "k8s.io/kubernetes/cmd/kubeadm/app/apis/output/scheme"
 	"k8s.io/kubernetes/cmd/kubeadm/app/constants"
 	kubeadmutil "k8s.io/kubernetes/cmd/kubeadm/app/util"
 	configutil "k8s.io/kubernetes/cmd/kubeadm/app/util/config"
+	"k8s.io/kubernetes/cmd/kubeadm/app/util/output"
 	utilruntime "k8s.io/kubernetes/cmd/kubeadm/app/util/runtime"
 	"k8s.io/utils/exec"
 	fakeexec "k8s.io/utils/exec/testing"
@@ -94,6 +96,12 @@ func TestImagesListRunWithCustomConfigPath(t *testing.T) {
 		},
 	}
 
+	outputFlags := output.NewOutputFlags(&imageTextPrintFlags{}).WithTypeSetter(outputapischeme.Scheme).WithDefaultOutput(output.TextOutput)
+	printer, err := outputFlags.ToPrinter()
+	if err != nil {
+		t.Fatalf("can't create printer for the output format %s: %+v", output.TextOutput, err)
+	}
+
 	for _, tc := range testcases {
 		t.Run(tc.name, func(t *testing.T) {
 			tmpDir, err := ioutil.TempDir("", "kubeadm-images-test")
@@ -114,7 +122,7 @@ func TestImagesListRunWithCustomConfigPath(t *testing.T) {
 				t.Fatalf("Failed getting the kubeadm images command: %v", err)
 			}
 			var output bytes.Buffer
-			if i.Run(&output) != nil {
+			if err = i.Run(&output, printer); err != nil {
 				t.Fatalf("Error from running the images command: %v", err)
 			}
 			actual := strings.Split(output.String(), "\n")
@@ -175,6 +183,11 @@ func TestConfigImagesListRunWithoutPath(t *testing.T) {
 		},
 	}
 
+	outputFlags := output.NewOutputFlags(&imageTextPrintFlags{}).WithTypeSetter(outputapischeme.Scheme).WithDefaultOutput(output.TextOutput)
+	printer, err := outputFlags.ToPrinter()
+	if err != nil {
+		t.Fatalf("can't create printer for the output format %s: %+v", output.TextOutput, err)
+	}
 	for _, tc := range testcases {
 		t.Run(tc.name, func(t *testing.T) {
 			i, err := NewImagesList("", &tc.cfg)
@@ -183,7 +196,8 @@ func TestConfigImagesListRunWithoutPath(t *testing.T) {
 			}
 
 			var output bytes.Buffer
-			if i.Run(&output) != nil {
+
+			if err = i.Run(&output, printer); err != nil {
 				t.Fatalf("did not expect an error running the Images command: %v", err)
 			}
 
@@ -195,6 +209,119 @@ func TestConfigImagesListRunWithoutPath(t *testing.T) {
 	}
 }
 
+func TestConfigImagesListOutput(t *testing.T) {
+	testcases := []struct {
+		name           string
+		cfg            kubeadmapiv1beta2.ClusterConfiguration
+		outputFormat   string
+		expectedOutput string
+	}{
+		{
+			name: "text output",
+			cfg: kubeadmapiv1beta2.ClusterConfiguration{
+				KubernetesVersion: dummyKubernetesVersion,
+			},
+			outputFormat: "text",
+			expectedOutput: `k8s.gcr.io/kube-apiserver:v1.16.0
+k8s.gcr.io/kube-controller-manager:v1.16.0
+k8s.gcr.io/kube-scheduler:v1.16.0
+k8s.gcr.io/kube-proxy:v1.16.0
+k8s.gcr.io/pause:3.2
+k8s.gcr.io/etcd:3.3.17-0
+k8s.gcr.io/coredns:1.6.5
+`,
+		},
+		{
+			name: "JSON output",
+			cfg: kubeadmapiv1beta2.ClusterConfiguration{
+				KubernetesVersion: dummyKubernetesVersion,
+			},
+			outputFormat: "json",
+			expectedOutput: `{
+    "kind": "Images",
+    "apiVersion": "output.kubeadm.k8s.io/v1alpha1",
+    "images": [
+        "k8s.gcr.io/kube-apiserver:v1.16.0",
+        "k8s.gcr.io/kube-controller-manager:v1.16.0",
+        "k8s.gcr.io/kube-scheduler:v1.16.0",
+        "k8s.gcr.io/kube-proxy:v1.16.0",
+        "k8s.gcr.io/pause:3.2",
+        "k8s.gcr.io/etcd:3.3.17-0",
+        "k8s.gcr.io/coredns:1.6.5"
+    ]
+}
+`,
+		},
+		{
+			name: "YAML output",
+			cfg: kubeadmapiv1beta2.ClusterConfiguration{
+				KubernetesVersion: dummyKubernetesVersion,
+			},
+			outputFormat: "yaml",
+			expectedOutput: `apiVersion: output.kubeadm.k8s.io/v1alpha1
+images:
+- k8s.gcr.io/kube-apiserver:v1.16.0
+- k8s.gcr.io/kube-controller-manager:v1.16.0
+- k8s.gcr.io/kube-scheduler:v1.16.0
+- k8s.gcr.io/kube-proxy:v1.16.0
+- k8s.gcr.io/pause:3.2
+- k8s.gcr.io/etcd:3.3.17-0
+- k8s.gcr.io/coredns:1.6.5
+kind: Images
+`,
+		},
+		{
+			name: "go-template output",
+			cfg: kubeadmapiv1beta2.ClusterConfiguration{
+				KubernetesVersion: dummyKubernetesVersion,
+			},
+			outputFormat: `go-template={{range .images}}{{.}}{{"\n"}}{{end}}`,
+			expectedOutput: `k8s.gcr.io/kube-apiserver:v1.16.0
+k8s.gcr.io/kube-controller-manager:v1.16.0
+k8s.gcr.io/kube-scheduler:v1.16.0
+k8s.gcr.io/kube-proxy:v1.16.0
+k8s.gcr.io/pause:3.2
+k8s.gcr.io/etcd:3.3.17-0
+k8s.gcr.io/coredns:1.6.5
+`,
+		},
+		{
+			name: "JSONPATH output",
+			cfg: kubeadmapiv1beta2.ClusterConfiguration{
+				KubernetesVersion: dummyKubernetesVersion,
+			},
+			outputFormat: `jsonpath={range.images[*]}{@} {end}`,
+			expectedOutput: "k8s.gcr.io/kube-apiserver:v1.16.0 k8s.gcr.io/kube-controller-manager:v1.16.0 k8s.gcr.io/kube-scheduler:v1.16.0 " +
+				"k8s.gcr.io/kube-proxy:v1.16.0 k8s.gcr.io/pause:3.2 k8s.gcr.io/etcd:3.3.17-0 k8s.gcr.io/coredns:1.6.5 ",
+		},
+	}
+
+	for _, tc := range testcases {
+		outputFlags := output.NewOutputFlags(&imageTextPrintFlags{}).WithTypeSetter(outputapischeme.Scheme).WithDefaultOutput(tc.outputFormat)
+		printer, err := outputFlags.ToPrinter()
+		if err != nil {
+			t.Fatalf("can't create printer for the output format %s: %+v", tc.outputFormat, err)
+		}
+
+		t.Run(tc.name, func(t *testing.T) {
+			i, err := NewImagesList("", &tc.cfg)
+			if err != nil {
+				t.Fatalf("did not expect an error while creating the Images command: %v", err)
+			}
+
+			var output bytes.Buffer
+
+			if err = i.Run(&output, printer); err != nil {
+				t.Fatalf("did not expect an error running the Images command: %v", err)
+			}
+
+			if output.String() != tc.expectedOutput {
+				t.Fatalf("unexpected output:\n|%s|\nexpected:\n|%s|\n", output.String(), tc.expectedOutput)
+			}
+		})
+	}
+}
+
 func TestImagesPull(t *testing.T) {
 	fcmd := fakeexec.FakeCmd{
 		CombinedOutputScript: []fakeexec.FakeAction{