Implement gwctl get namespace

gwctl/cmd/get.go

@@ -35,7 +35,7 @@ func NewGetCommand() *cobra.Command {
 	var allNamespacesFlag bool
 
 	cmd := &cobra.Command{
-		Use:   "get {gateways|gatewayclasses|policies|policycrds|httproutes}",
+		Use:   "get {namespaces|gateways|gatewayclasses|policies|policycrds|httproutes}",
 		Short: "Display one or many resources",
 		Args:  cobra.ExactArgs(1),
 		Run: func(cmd *cobra.Command, args []string) {
@@ -72,12 +72,21 @@ func runGet(cmd *cobra.Command, args []string, params *utils.CmdParams) {
 		PolicyManager: params.PolicyManager,
 	}
 	realClock := clock.RealClock{}
+	nsPrinter := &printer.NamespacesPrinter{Out: params.Out, Clock: realClock}
 	gwPrinter := &printer.GatewaysPrinter{Out: params.Out, Clock: realClock}
 	gwcPrinter := &printer.GatewayClassesPrinter{Out: params.Out, Clock: realClock}
 	policiesPrinter := &printer.PoliciesPrinter{Out: params.Out, Clock: realClock}
 	httpRoutesPrinter := &printer.HTTPRoutesPrinter{Out: params.Out, Clock: realClock}
 
 	switch kind {
+	case "namespace", "namespaces":
+		resourceModel, err := discoverer.DiscoverResourcesForNamespace(resourcediscovery.Filter{})
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "failed to discover Namespace resources: %v\n", err)
+			os.Exit(1)
+		}
+		nsPrinter.Print(resourceModel)
+
 	case "gateway", "gateways":
 		filter := resourcediscovery.Filter{Namespace: ns}
 		if len(args) > 1 {

gwctl/pkg/printer/namespace.go

@@ -21,14 +21,20 @@ import (
 	"io"
 	"os"
 	"sort"
+	"strings"
+	"text/tabwriter"
+
+	"k8s.io/apimachinery/pkg/util/duration"
+	"k8s.io/utils/clock"
 
 	"sigs.k8s.io/gateway-api/gwctl/pkg/policymanager"
 	"sigs.k8s.io/gateway-api/gwctl/pkg/resourcediscovery"
 	"sigs.k8s.io/yaml"
 )
 
 type NamespacesPrinter struct {
-	Out io.Writer
+	Out   io.Writer
+	Clock clock.Clock
 }
 
 type namespaceDescribeView struct {
@@ -39,6 +45,32 @@ type namespaceDescribeView struct {
 	DirectlyAttachedPolicies []policymanager.ObjRef `json:",omitempty"`
 }
 
+func (nsp *NamespacesPrinter) Print(resourceModel *resourcediscovery.ResourceModel) {
+	tw := tabwriter.NewWriter(nsp.Out, 0, 0, 2, ' ', 0)
+	row := []string{"NAME", "STATUS", "AGE"}
+	tw.Write([]byte(strings.Join(row, "\t") + "\n"))
+
+	namespaceNodes := make([]*resourcediscovery.NamespaceNode, 0, len(resourceModel.Namespaces))
+	for _, namespaceNode := range resourceModel.Namespaces {
+		namespaceNodes = append(namespaceNodes, namespaceNode)
+	}
+
+	sort.Slice(namespaceNodes, func(i, j int) bool {
+		return namespaceNodes[i].Namespace.Name < namespaceNodes[j].Namespace.Name
+	})
+
+	for _, namespaceNode := range namespaceNodes {
+		age := duration.HumanDuration(nsp.Clock.Since(namespaceNode.Namespace.CreationTimestamp.Time))
+		row := []string{
+			namespaceNode.Namespace.Name,
+			string(namespaceNode.Namespace.Status.Phase),
+			age,
+		}
+		tw.Write([]byte(strings.Join(row, "\t") + "\n"))
+	}
+	tw.Flush()
+}
+
 func (nsp *NamespacesPrinter) PrintDescribeView(resourceModel *resourcediscovery.ResourceModel) {
 	namespaceNodes := make([]*resourcediscovery.NamespaceNode, 0, len(resourceModel.Namespaces))
 

gwctl/pkg/printer/namespace_test.go

@@ -19,20 +19,92 @@ package printer
 import (
 	"bytes"
 	"testing"
+	"time"
 
 	"github.com/google/go-cmp/cmp"
+
 	corev1 "k8s.io/api/core/v1"
 	apiextensionsv1 "k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
 	"k8s.io/apimachinery/pkg/runtime"
+	testingclock "k8s.io/utils/clock/testing"
+
 	gatewayv1alpha2 "sigs.k8s.io/gateway-api/apis/v1alpha2"
-	"sigs.k8s.io/gateway-api/gwctl/pkg/utils"
 	"sigs.k8s.io/gateway-api/gwctl/pkg/common"
 	"sigs.k8s.io/gateway-api/gwctl/pkg/resourcediscovery"
+	"sigs.k8s.io/gateway-api/gwctl/pkg/utils"
 )
 
+func TestNamespacePrinter_Print(t *testing.T) {
+	fakeClock := testingclock.NewFakeClock(time.Now())
+	objects := []runtime.Object{
+		&corev1.Namespace{
+			ObjectMeta: metav1.ObjectMeta{
+				Name: "default",
+				CreationTimestamp: metav1.Time{
+					Time: fakeClock.Now().Add(-46 * 24 * time.Hour),
+				},
+			},
+			Status: corev1.NamespaceStatus{
+				Phase: corev1.NamespaceActive,
+			},
+		},
+		&corev1.Namespace{
+			ObjectMeta: metav1.ObjectMeta{
+				Name: "kube-system",
+				CreationTimestamp: metav1.Time{
+					Time: fakeClock.Now().Add(-46 * 24 * time.Hour),
+				},
+			},
+			Status: corev1.NamespaceStatus{
+				Phase: corev1.NamespaceActive,
+			},
+		},
+		&corev1.Namespace{
+			ObjectMeta: metav1.ObjectMeta{
+				Name: "ns1",
+				CreationTimestamp: metav1.Time{
+					Time: fakeClock.Now().Add(-10 * time.Minute),
+				},
+			},
+			Status: corev1.NamespaceStatus{
+				Phase: corev1.NamespaceTerminating,
+			},
+		},
+	}
+
+	params := utils.MustParamsForTest(t, common.MustClientsForTest(t, objects...))
+	discoverer := resourcediscovery.Discoverer{
+		K8sClients:    params.K8sClients,
+		PolicyManager: params.PolicyManager,
+	}
+	resourceModel, err := discoverer.DiscoverResourcesForNamespace(resourcediscovery.Filter{})
+	if err != nil {
+		t.Fatalf("Failed to construct resourceModel: %v", resourceModel)
+	}
+
+	nsp := &NamespacesPrinter{
+		Out:   params.Out,
+		Clock: fakeClock,
+	}
+	nsp.Print(resourceModel)
+
+	got := params.Out.(*bytes.Buffer).String()
+	want := `
+NAME         STATUS       AGE
+default      Active       46d
+kube-system  Active       46d
+ns1          Terminating  10m
+`
+
+	if diff := cmp.Diff(common.YamlString(want), common.YamlString(got), common.YamlStringTransformer); diff != "" {
+		t.Errorf("Unexpected diff\ngot=\n%v\nwant=\n%v\ndiff (-want +got)=\n%v", got, want, diff)
+	}
+}
+
 func TestNamespacePrinter_PrintDescribeView(t *testing.T) {
+	fakeClock := testingclock.NewFakeClock(time.Now())
 	objects := []runtime.Object{
 		// Defining a Namespace called development
 		&corev1.Namespace{
@@ -153,7 +225,8 @@ func TestNamespacePrinter_PrintDescribeView(t *testing.T) {
 	}
 
 	nsp := &NamespacesPrinter{
-		Out: params.Out,
+		Out:   params.Out,
+		Clock: fakeClock,
 	}
 	nsp.PrintDescribeView(resourceModel)