Add rudimentary implementation

cmd/cmd.go

@@ -0,0 +1,120 @@
+package cmd
+
+import (
+	"context"
+	"fmt"
+	"os"
+
+	"github.com/spf13/cobra"
+	corev1 "k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/cli-runtime/pkg/genericclioptions"
+	"k8s.io/cli-runtime/pkg/printers"
+	"k8s.io/client-go/kubernetes"
+)
+
+func NewUnreadyCmd(ctx context.Context) *cobra.Command {
+	var kubernetesConfigFlags *genericclioptions.ConfigFlags
+	var allNamespacesFlag bool
+
+	cmd := &cobra.Command{
+		Use:          "unready",
+		SilenceUsage: true,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			if kubernetesConfigFlags.Namespace == nil || *kubernetesConfigFlags.Namespace == "" {
+				kubernetesConfigFlags.Namespace = new("default")
+			}
+			return run(ctx, kubernetesConfigFlags, allNamespacesFlag)
+		},
+	}
+
+	kubernetesConfigFlags = genericclioptions.NewConfigFlags(false)
+	kubernetesConfigFlags.AddFlags(cmd.Flags())
+
+	cmd.Flags().BoolVarP(&allNamespacesFlag, "all-namespaces", "A", false, "If present, list unready pods across all namespaces.")
+
+	return cmd
+}
+
+func run(ctx context.Context, configFlags *genericclioptions.ConfigFlags, allNamespaces bool) error {
+	config, err := configFlags.ToRESTConfig()
+	if err != nil {
+		return fmt.Errorf("failed to read kubeconfig: %w", err)
+	}
+
+	clientset, err := kubernetes.NewForConfig(config)
+	if err != nil {
+		return fmt.Errorf("failed to create clientset: %w", err)
+	}
+
+	namespace := *configFlags.Namespace
+	if allNamespaces {
+		namespace = ""
+	}
+
+	pods, err := clientset.CoreV1().Pods(namespace).List(ctx, metav1.ListOptions{})
+	if err != nil {
+		return fmt.Errorf("failed listing Pods: %w", err)
+	}
+
+	filtered := make([]corev1.Pod, 0)
+
+	for _, pod := range pods.Items {
+		if isNotReady(pod) {
+			filtered = append(filtered, pod)
+		}
+	}
+
+	return print(filtered)
+}
+
+func print(pods []corev1.Pod) error {
+	table := metav1.Table{
+		ColumnDefinitions: []metav1.TableColumnDefinition{
+			{Name: "Namespace"},
+			{Name: "Name"},
+			{Name: "Ready"},
+			{Name: "Status"},
+		},
+	}
+	for _, pod := range pods {
+		table.Rows = append(table.Rows, metav1.TableRow{
+			Cells: []any{
+				pod.Namespace,
+				pod.Name,
+				containerStatuses(pod),
+				pod.Status.Phase,
+			},
+		})
+	}
+
+	printer := printers.NewTablePrinter(printers.PrintOptions{})
+	return printer.PrintObj(&table, os.Stdout)
+}
+
+func containerStatuses(pod corev1.Pod) string {
+	ready := 0
+	unready := 0
+	for _, status := range pod.Status.ContainerStatuses {
+		if status.Ready {
+			ready++
+		} else {
+			unready++
+		}
+	}
+
+	return fmt.Sprintf("%d/%d", ready, ready+unready)
+}
+
+func isNotReady(pod corev1.Pod) bool {
+	return hasUnreadyContainers(pod) && pod.Status.Phase != corev1.PodSucceeded
+}
+
+func hasUnreadyContainers(pod corev1.Pod) bool {
+	for _, ctr := range pod.Status.ContainerStatuses {
+		if !ctr.Ready {
+			return true
+		}
+	}
+	return false
+}