feat(show/nodes): display running pods count(deployment,statefulsets)…

… on nodes

main.go

@@ -14,10 +14,12 @@ func main() {
 	rootCmd, cfg := cmd.NewRootCmd()
 	restartCmd := cmd.NewRestartCmd(cfg)
 	drainCmd := cmd.NewDrainCmd(cfg)
+	showCmd := cmd.NewShowCmd(cfg)
 
 	rootCmd.Subcommands = []*ffcli.Command{
 		restartCmd,
 		drainCmd,
+		showCmd,
 	}
 
 	if err := rootCmd.Parse(os.Args[1:]); err != nil {

pkg/cmd/show.go

@@ -0,0 +1,25 @@
+package cmd
+
+import (
+	"context"
+	"flag"
+
+	"github.com/peterbourgon/ff/v3/ffcli"
+)
+
+func NewShowCmd(rootCfg *RootConfig) *ffcli.Command {
+	showNodesCmd := NewShowNodesCmd(rootCfg)
+
+	c := &ffcli.Command{
+		Name:       "show",
+		ShortUsage: "show details of nodes or resources",
+		ShortHelp:  "show details of nodes or resources",
+		Exec: func(context.Context, []string) error {
+			return flag.ErrHelp
+		},
+	}
+	c.Subcommands = []*ffcli.Command{
+		showNodesCmd,
+	}
+	return c
+}

pkg/cmd/show_nodes.go

@@ -0,0 +1,133 @@
+package cmd
+
+import (
+	"context"
+	"flag"
+
+	"github.com/fatih/color"
+	"github.com/peterbourgon/ff/v3"
+	"github.com/peterbourgon/ff/v3/ffcli"
+	"github.com/rodaine/table"
+
+	v1 "k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/fields"
+)
+
+type NodeInfo struct {
+	Node          v1.Node
+	Deployments   []v1.Pod
+	Statusfulsets []v1.Pod
+}
+
+type ShowNodesConfig struct {
+	rootCfg       *RootConfig
+	labelSelector string
+}
+
+func NewShowNodesCmd(rootCfg *RootConfig) *ffcli.Command {
+	cfg := &ShowNodesConfig{
+		rootCfg: rootCfg,
+	}
+
+	fs := flag.NewFlagSet("kroller show nodes", flag.ExitOnError)
+	fs.String("config", "", "config file (optional)")
+	fs.StringVar(&cfg.labelSelector, "l", "", "selector (label query) to filter on, supports '=', '==', and '!='.(e.g. -l key1=value1,key2=value2)")
+
+	rootCfg.RegisterFlags(fs)
+
+	c := &ffcli.Command{
+		Name:       "nodes",
+		ShortUsage: "show details of nodes",
+		ShortHelp:  "show details of nodes",
+		FlagSet:    fs,
+		Options: []ff.Option{
+			ff.WithEnvVarNoPrefix(),
+			ff.WithConfigFileFlag("config"),
+			ff.WithConfigFileParser(ff.PlainParser),
+		},
+		Exec: cfg.Exec,
+	}
+
+	return c
+}
+
+func (c *ShowNodesConfig) Exec(ctx context.Context, args []string) error {
+	//verbose := c.rootCfg.Verbose
+	kubeCli := c.rootCfg.KubeClient
+
+	selector, err := fields.ParseSelector(c.labelSelector)
+	if err != nil {
+		return err
+	}
+
+	nodes, err := kubeCli.Nodes(ctx, selector)
+	if err != nil {
+		return err
+	}
+
+	var nodeInfos []*NodeInfo
+	for _, n := range nodes.Items {
+		pods, err := kubeCli.PodsOnNode(ctx, n.Name)
+		if err != nil {
+			return err
+		}
+
+		var (
+			deploys []v1.Pod
+			sts     []v1.Pod
+		)
+		for _, p := range pods.Items {
+			if isDeploymentPod(&p) {
+				deploys = append(deploys, p)
+				continue
+			}
+			if isStatefulSetPod(&p) {
+				sts = append(sts, p)
+			}
+		}
+
+		ni := &NodeInfo{
+			Node:          n,
+			Deployments:   deploys,
+			Statusfulsets: sts,
+		}
+		nodeInfos = append(nodeInfos, ni)
+	}
+
+	tbl := table.New("Node", "Deployment", "Statusfulsets")
+	headerFmt := color.New(color.FgGreen, color.Underline).SprintfFunc()
+	columnFmt := color.New(color.FgYellow).SprintfFunc()
+	tbl.WithHeaderFormatter(headerFmt).WithFirstColumnFormatter(columnFmt)
+
+	for _, n := range nodeInfos {
+		tbl.AddRow(n.Node.Name, len(n.Deployments), len(n.Statusfulsets))
+	}
+
+	tbl.Print()
+
+	return nil
+}
+
+func isDeploymentPod(p *v1.Pod) bool {
+	controllerRef := metav1.GetControllerOf(p)
+	if controllerRef == nil {
+		return false
+	}
+	if controllerRef.Kind == "ReplicaSet" {
+		return true
+	}
+
+	return false
+}
+
+func isStatefulSetPod(p *v1.Pod) bool {
+	controllerRef := metav1.GetControllerOf(p)
+	if controllerRef == nil {
+		return false
+	}
+	if controllerRef.Kind == "StatefulSet" {
+		return true
+	}
+	return false
+}

pkg/kubernetes/node.go

@@ -10,6 +10,17 @@ import (
 	"k8s.io/apimachinery/pkg/fields"
 )
 
+func (c *Client) Nodes(ctx context.Context, labelSelector fields.Selector) (*v1.NodeList, error) {
+	nodes, err := c.clientset.CoreV1().Nodes().List(ctx, metav1.ListOptions{
+		LabelSelector: labelSelector.String(),
+	})
+	if err != nil {
+		return nil, errors.Wrap(err, "failed to find nodes")
+	}
+
+	return nodes, nil
+}
+
 func (c *Client) Node(ctx context.Context, nodeName string) (*v1.Node, error) {
 	node, err := c.clientset.CoreV1().Nodes().Get(ctx, nodeName, metav1.GetOptions{})
 	if err != nil {