Add output format options to 'get'

Signed-off-by: Phil Dibowitz <[email protected]>

README.md

@@ -42,8 +42,6 @@ of asking systemd to list all services on a node. :)
 kubectl d get -N <nodename>
 ```
 
-NOTE: `-o` is not yet implemented for `get`.
-
 Or you can delete the pod from a daemonset on a specific node
 
 ```bash

cmd/get.go

@@ -1,20 +1,26 @@
 package cmd
 
 import (
+    "encoding/json"
+    "gopkg.in/yaml.v3"
     "fmt"
     "github.com/spf13/cobra"
     "io"
     "os"
+    "strings"
+    "time"
 
     metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
     "k8s.io/cli-runtime/pkg/printers"
-
+    v1 "k8s.io/api/core/v1"
 )
 
 
 func newDshGetCommand(
     out io.Writer, namespace *string, nodeName *string,
 ) *cobra.Command {
+    var output string
+
     dshGet := &dshCmd{
         out: out,
     }
@@ -28,15 +34,19 @@ func newDshGetCommand(
             if len(args) == 1 {
                 ds = args[0]
             }
-            return dshGet.getPods(*namespace, ds, *nodeName)
+            return dshGet.getPods(*namespace, ds, *nodeName, output)
         },
     }
 
+    cmd.Flags().StringVarP(
+        &output, "output", "o", "", "Output format. One of wide, json, yaml.",
+    )
+
     return cmd
 }
 
 func (sv *dshCmd) getPods(
-    namespace string, ds string, nodeName string,
+    namespace string, ds string, nodeName string, output string,
 ) error {
     clientset, err := getClientSet()
     if err != nil {
@@ -53,32 +63,112 @@ func (sv *dshCmd) getPods(
         return nil
     }
 
-    printer := printers.NewTablePrinter(printers.PrintOptions{})
-    table := metav1.Table{
-        ColumnDefinitions: []metav1.TableColumnDefinition{
-            {Name: "NAME"},
-            {Name: "READY"},
-            {Name: "STATUS"},
-            {Name: "RESTARTS"},
-            {Name: "AGE"},
-        },
+    var table metav1.Table
+    var printer printers.ResourcePrinter
+    if output == "" || output == "wide" {
+        printer = printers.NewTablePrinter(printers.PrintOptions{})
+        if output == "" {
+            table = metav1.Table{
+                ColumnDefinitions: []metav1.TableColumnDefinition{
+                    {Name: "NAME"},
+                    {Name: "READY"},
+                    {Name: "STATUS"},
+                    {Name: "RESTARTS"},
+                    {Name: "AGE"},
+                },
+            }
+        } else if output == "wide" {
+            // when I append(table.ColumnDefinitions, ...) I get
+            // syntax errors. No idea why.
+            table = metav1.Table{
+                ColumnDefinitions: []metav1.TableColumnDefinition{
+                    {Name: "NAME"},
+                    {Name: "READY"},
+                    {Name: "STATUS"},
+                    {Name: "RESTARTS"},
+                    {Name: "AGE"},
+                    {Name: "IP"},
+                    {Name: "NODE"},
+                    {Name: "NOMINATED NODE"},
+                    {Name: "READINESS GATES"},
+                },
+            }
+        }
     }
 
     for _, pod := range pods {
-        readyCount, totalCount :=
-            countReadyContainers(pod.Status.ContainerStatuses)
-        row := metav1.TableRow{
-            Cells: []interface{}{
-                pod.Name,
-                fmt.Sprintf("%d/%d", readyCount, totalCount),
-                string(pod.Status.Phase),
-                fmt.Sprintf("%d", pod.Status.ContainerStatuses[0].RestartCount),
-                pod.ObjectMeta.CreationTimestamp.Time.String(),
-            },
+        switch output {
+        case "json":
+            jsonData, err := json.MarshalIndent(pod, "", "    ")
+            if err != nil {
+                return err
+            }
+            fmt.Println(string(jsonData))
+        case "yaml":
+            yamlData, err := yaml.Marshal(pod)
+            if err != nil {
+                return err
+            }
+            fmt.Println(string(yamlData))
+        case "", "wide":
+            readyCount, totalCount :=
+                countReadyContainers(pod.Status.ContainerStatuses)
+            age := time.Since(pod.ObjectMeta.CreationTimestamp.Time).Round(
+                time.Second,
+            )
+            row := metav1.TableRow{
+                Cells: []interface{}{
+                    pod.Name,
+                    fmt.Sprintf("%d/%d", readyCount, totalCount),
+                    string(pod.Status.Phase),
+                    fmt.Sprintf(
+                        "%d",
+                        pod.Status.ContainerStatuses[0].RestartCount,
+                    ),
+                    age,
+                },
+            }
+            if (output == "wide") {
+                nominatedNode := "<none>"
+                if pod.Status.NominatedNodeName != "" {
+                    nominatedNode = pod.Status.NominatedNodeName
+                }
+                var readinessGates []string
+                ready := false
+                for _, condition := range pod.Status.Conditions {
+                    if condition.Type == v1.PodReady &&
+                            condition.Status == v1.ConditionTrue {
+                        ready = true
+                        break
+                    }
+                    readinessGates = append(
+                        readinessGates,
+                        string(condition.Type),
+                    )
+                }
+                var readinessGatesStr string
+                if ready || len(readinessGates) == 0 {
+                    readinessGatesStr = "<none>"
+                } else {
+                    readinessGatesStr = strings.Join(readinessGates, ", ")
+                }
+
+                row.Cells = append(
+                    row.Cells,
+                    pod.Status.PodIP,
+                    pod.Spec.NodeName,
+                    nominatedNode,
+                    readinessGatesStr,
+                )
+            }
+
+            table.Rows = append(table.Rows, row)
         }
-        table.Rows = append(table.Rows, row)
     }
 
-    err = printer.PrintObj(&table, os.Stdout)
-    return err
+    if output == "" || output == "wide" {
+        err = printer.PrintObj(&table, os.Stdout)
+        return err
+    }
+    return nil
 }

go.mod

@@ -5,6 +5,7 @@ go 1.21.4
 require (
 	github.com/spf13/cobra v1.8.0
 	golang.org/x/text v0.14.0
+	gopkg.in/yaml.v3 v3.0.1
 	k8s.io/api v0.29.2
 	k8s.io/apimachinery v0.29.2
 	k8s.io/cli-runtime v0.29.2
@@ -55,7 +56,6 @@ require (
 	google.golang.org/protobuf v1.31.0 // indirect
 	gopkg.in/inf.v0 v0.9.1 // indirect
 	gopkg.in/yaml.v2 v2.4.0 // indirect
-	gopkg.in/yaml.v3 v3.0.1 // indirect
 	k8s.io/klog/v2 v2.110.1 // indirect
 	k8s.io/kube-openapi v0.0.0-20231010175941-2dd684a91f00 // indirect
 	k8s.io/utils v0.0.0-20230726121419-3b25d923346b // indirect