separate data extraction from printing; add options and formats

go.mod

@@ -4,6 +4,7 @@ go 1.14
 
 require (
 	github.com/fatih/color v1.9.0
+	github.com/olekukonko/tablewriter v0.0.0-20170122224234-a0225b3f23b5
 	github.com/pkg/errors v0.9.1
 	github.com/sirupsen/logrus v1.4.2
 	github.com/spf13/cobra v1.0.0

go.sum

@@ -299,6 +299,7 @@ github.com/mattn/go-isatty v0.0.4/go.mod h1:M+lRXTBqGeGNdLjl/ufCoiOlB5xdOkqRJdNx
 github.com/mattn/go-isatty v0.0.8/go.mod h1:Iq45c/XA43vh69/j3iqttzPXn0bhXyGjM0Hdxcsrc5s=
 github.com/mattn/go-isatty v0.0.11 h1:FxPOTFNqGkuDUGi3H/qkUbQO4ZiBa2brKq5r0l8TGeM=
 github.com/mattn/go-isatty v0.0.11/go.mod h1:PhnuNfih5lzO57/f3n+odYbM4JtupLOxQOAqxQCu2WE=
+github.com/mattn/go-runewidth v0.0.2 h1:UnlwIPBGaTZfPQ6T1IGzPI0EkYAQmT9fAEJ/poFC63o=
 github.com/mattn/go-runewidth v0.0.2/go.mod h1:LwmH8dsx7+W8Uxz3IHJYH5QSwggIsqBzpuz5H//U1FU=
 github.com/matttproud/golang_protobuf_extensions v1.0.1/go.mod h1:D8He9yQNgCq6Z5Ld7szi9bcBfOoFv/3dc6xSMkL2PC0=
 github.com/miekg/dns v1.0.14/go.mod h1:W1PPwlIAgtquWBMBEV9nkV9Cazfe8ScdGz/Lj7v3Nrg=
@@ -325,6 +326,7 @@ github.com/mwitkow/go-conntrack v0.0.0-20161129095857-cc309e4a2223/go.mod h1:qRW
 github.com/mxk/go-flowrate v0.0.0-20140419014527-cca7078d478f/go.mod h1:ZdcZmHo+o7JKHSa8/e818NopupXU1YMK5fe1lsApnBw=
 github.com/oklog/run v1.0.0/go.mod h1:dlhp/R75TPv97u0XWUtDeV/lRKWPKSdTuV0TZvrmrQA=
 github.com/oklog/ulid v1.3.1/go.mod h1:CirwcVhetQ6Lv90oh/F+FBtV6XMibvdAFo93nm5qn4U=
+github.com/olekukonko/tablewriter v0.0.0-20170122224234-a0225b3f23b5 h1:58+kh9C6jJVXYjt8IE48G2eWl6BjwU5Gj0gqY84fy78=
 github.com/olekukonko/tablewriter v0.0.0-20170122224234-a0225b3f23b5/go.mod h1:vsDQFd/mU46D+Z4whnwzcISnGGzXWMclvtLoiIKAKIo=
 github.com/onsi/ginkgo v0.0.0-20170829012221-11459a886d9c/go.mod h1:lLunBs/Ym6LB5Z9jYTR76FiuTmxDTDusOGeTQH+WWjE=
 github.com/onsi/ginkgo v1.6.0/go.mod h1:lLunBs/Ym6LB5Z9jYTR76FiuTmxDTDusOGeTQH+WWjE=

pkg/cli/root.go

@@ -1,22 +1,18 @@
 package cli
 
 import (
+	"encoding/json"
 	"fmt"
 	"github.com/mattfenwick/krew-node-pod/pkg/plugin"
+	"github.com/pkg/errors"
 	v1 "k8s.io/api/core/v1"
-	//"os"
+	"os"
 	"sort"
+	"strings"
 
-	//"strings"
-	//"time"
-
+	"github.com/olekukonko/tablewriter"
 	log "github.com/sirupsen/logrus"
-	//"github.com/mattfenwick/krew-node-pod/pkg/logger"
-	//"github.com/mattfenwick/krew-node-pod/pkg/plugin"
-	//"github.com/pkg/errors"
 	"github.com/spf13/cobra"
-	//"github.com/spf13/viper"
-	//"github.com/tj/go-spin"
 	"k8s.io/cli-runtime/pkg/genericclioptions"
 )
 
@@ -26,20 +22,28 @@ func doOrDie(err error) {
 	}
 }
 
+func InitAndExecute() {
+	rootCmd := setupRootCmd()
+	if err := rootCmd.Execute(); err != nil {
+		log.Fatalf("%+v", err)
+	}
+}
+
 type Config struct {
-	LogLevel  string
-	KubeFlags *genericclioptions.ConfigFlags
+	LogLevel       string
+	KubeFlags      *genericclioptions.ConfigFlags
+	ShowContainers bool
+	Format         string
 }
 
 func setupRootCmd() *cobra.Command {
 	args := &Config{}
 
 	cmd := &cobra.Command{
-		Use:           "node-pod",
-		Short:         "",
-		Long:          `.`,
-		SilenceErrors: true,
-		SilenceUsage:  true,
+		Use:   "node-pod",
+		Short: "",
+		Long:  `.`,
+		Args:  cobra.ExactArgs(0),
 		RunE: func(cmd *cobra.Command, as []string) error {
 			// TODO detect whether this is running under kubectl or not, and modify help message accordingly
 			//   see https://krew.sigs.k8s.io/docs/developer-guide/develop/best-practices/#auth-plugins
@@ -51,62 +55,204 @@ func setupRootCmd() *cobra.Command {
 
 	cmd.Flags().StringVar(&args.LogLevel, "v", "info", "log level")
 
+	cmd.Flags().StringVar(&args.Format, "format", "list", "output format: one of json, list, table")
+
+	cmd.Flags().BoolVarP(&args.ShowContainers, "containers", "c", false, "if true, print containers")
+
 	args.KubeFlags = genericclioptions.NewConfigFlags(false)
 	args.KubeFlags.AddFlags(cmd.Flags())
 
 	return cmd
 }
 
-func InitAndExecute() {
-	rootCmd := setupRootCmd()
-	if err := rootCmd.Execute(); err != nil {
-		log.Fatalf("%+v", err)
-	}
-}
-
 func runRootCmd(args *Config) {
 	level, err := log.ParseLevel(args.LogLevel)
 	doOrDie(err)
 	log.SetLevel(level)
 
-	// TODO use args
-	ListPods()
-}
-
-func ListPods() {
-	client, err := plugin.NewDefaultClient()
+	client, err := plugin.NewClientWithDefaultKubeConfigFallback(*args.KubeFlags.KubeConfig)
 	doOrDie(err)
 
-	pods, err := client.ListPods(v1.NamespaceAll)
+	output, err := FetchKubeData(client, *args.KubeFlags.Namespace)
 	doOrDie(err)
 
-	nodeToPods := map[string][]v1.Pod{}
-	for _, pod := range pods.Items {
-		node := pod.Spec.NodeName
-		nodeToPods[node] = append(nodeToPods[node], pod)
+	if !args.ShowContainers {
+		output.RemoveContainers()
 	}
 
-	nodes := []string{}
-	for node := range nodeToPods {
-		nodes = append(nodes, node)
+	switch args.Format {
+	case "list":
+		fmt.Println(output.List())
+	case "json":
+		fmt.Println(output.Json())
+	case "table":
+		output.Table().Render()
+	default:
+		doOrDie(errors.Errorf("invalid format '%s'", args.Format))
 	}
+}
 
+type Output struct {
+	Nodes []*Node
+}
+
+func NewOutput(nodeMap map[string]*Node) *Output {
+	var nodes []*Node
+	for _, node := range nodeMap {
+		nodes = append(nodes, node)
+	}
 	sort.Slice(nodes, func(i, j int) bool {
-		return nodes[i] < nodes[j]
+		return nodes[i].Name < nodes[j].Name
 	})
-
 	for _, node := range nodes {
-		pods := nodeToPods[node]
+		pods := node.Pods
 		sort.Slice(pods, func(i, j int) bool {
 			if pods[i].Namespace != pods[j].Namespace {
 				return pods[i].Namespace < pods[j].Namespace
 			}
 			return pods[i].Name < pods[j].Name
 		})
-		fmt.Printf("%s:\n", node)
+		node.Pods = pods
 		for _, pod := range pods {
-			fmt.Printf(" - %s/%s\n", pod.Namespace, pod.Name)
+			containers := pod.Containers
+			sort.Slice(containers, func(i, j int) bool {
+				return containers[i].Name < containers[j].Name
+			})
+			pod.Containers = containers
+		}
+	}
+	return &Output{Nodes: nodes}
+}
+
+func (o *Output) RemoveContainers() {
+	for _, node := range o.Nodes {
+		for _, pod := range node.Pods {
+			pod.Containers = nil
+		}
+	}
+}
+
+func (o *Output) Json() string {
+	bytes, err := json.MarshalIndent(o, "", "  ")
+	doOrDie(err)
+	return string(bytes)
+}
+
+func (o *Output) Table() *tablewriter.Table {
+	table := tablewriter.NewWriter(os.Stdout)
+	table.SetHeader([]string{"Node", "Namespace", "Pod Name", "Container", "Status"})
+
+	for _, node := range o.Nodes {
+		table.Append([]string{node.Name, "", "", "", node.Status})
+
+		for _, pod := range node.Pods {
+			table.Append([]string{"", pod.Namespace, pod.Name, "", pod.Status})
+
+			for _, container := range pod.Containers {
+				table.Append([]string{"", "", "", container.Name, container.Status})
+			}
+		}
+	}
+
+	return table
+}
+
+func (o *Output) List() string {
+	var lines []string
+	for _, node := range o.Nodes {
+		lines = append(lines, fmt.Sprintf("%s: %s", node.Name, node.Status))
+		for _, pod := range node.Pods {
+			lines = append(lines, fmt.Sprintf(" - %s/%s: %s", pod.Namespace, pod.Name, pod.Status))
+			for _, container := range pod.Containers {
+				lines = append(lines, fmt.Sprintf("   - %s: %s", container.Name, container.Status))
+			}
+		}
+		lines = append(lines, "")
+	}
+	return strings.Join(lines, "\n")
+}
+
+type Node struct {
+	Name   string
+	Pods   []*Pod
+	Status string
+}
+
+type Pod struct {
+	Name       string
+	Namespace  string
+	Containers []*Container
+	Status     string
+}
+
+type Container struct {
+	Name   string
+	Status string
+}
+
+func FetchKubeData(client *plugin.Client, namespace string) (*Output, error) {
+	kubePods, err := client.ListPods(namespace)
+	if err != nil {
+		return nil, err
+	}
+
+	kubeNodes, err := client.ListNodes()
+	if err != nil {
+		return nil, err
+	}
+
+	// get the nodes
+	nodes := map[string]*Node{}
+	for _, kubeNode := range kubeNodes.Items {
+		var status = "unknown"
+		if len(kubeNode.Status.Conditions) > 0 {
+			status = string(kubeNode.Status.Conditions[len(kubeNode.Status.Conditions)-1].Type)
+		}
+		nodes[kubeNode.Name] = &Node{
+			Name:   kubeNode.Name,
+			Pods:   nil,
+			Status: status,
+		}
+	}
+
+	// add the pods into the nodes
+	for _, kubePod := range kubePods.Items {
+		nodeName := kubePod.Spec.NodeName
+		node, ok := nodes[nodeName]
+		if !ok {
+			return nil, errors.Errorf("pod %s/%s assigned to node %s -- but node not found in kube", kubePod.Namespace, kubePod.Name, nodeName)
 		}
-		fmt.Println()
+		// TODO methodize this
+		node.Pods = append(node.Pods, extractPod(&kubePod))
+	}
+
+	return NewOutput(nodes), err
+}
+
+func extractPod(kubePod *v1.Pod) *Pod {
+	var containers []*Container
+	for _, cont := range kubePod.Status.ContainerStatuses {
+		containers = append(containers, extractContainer(&cont))
+	}
+	return &Pod{
+		Name:       kubePod.Name,
+		Namespace:  kubePod.Namespace,
+		Containers: containers,
+		Status:     string(kubePod.Status.Phase),
+	}
+}
+
+func extractContainer(kubeContainer *v1.ContainerStatus) *Container {
+	state := "unknown"
+	if kubeContainer.State.Running != nil {
+		state = "running"
+	} else if kubeContainer.State.Terminated != nil {
+		state = "terminated"
+	} else if kubeContainer.State.Waiting != nil {
+		state = "waiting"
+	}
+	return &Container{
+		Name:   kubeContainer.Name,
+		Status: state,
 	}
 }

pkg/plugin/kubeclient.go

@@ -9,7 +9,8 @@ import (
 	log "github.com/sirupsen/logrus"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/client-go/kubernetes"
-	_ "k8s.io/client-go/plugin/pkg/client/auth" // required for auth, see: https://github.com/kubernetes/client-go/tree/v0.17.3/plugin/pkg/client/auth
+	// required for auth, see: https://github.com/kubernetes/client-go/tree/v0.17.3/plugin/pkg/client/auth
+	_ "k8s.io/client-go/plugin/pkg/client/auth"
 	"k8s.io/client-go/tools/clientcmd"
 )
 
@@ -33,6 +34,13 @@ func NewDefaultClient() (*Client, error) {
 	return NewClient(kubeConfigPath)
 }
 
+func NewClientWithDefaultKubeConfigFallback(kubeConfigPath string) (*Client, error) {
+	if kubeConfigPath == "" {
+		return NewDefaultClient()
+	}
+	return NewClient(kubeConfigPath)
+}
+
 func NewClient(kubeConfigPath string) (*Client, error) {
 	log.Debugf("instantiating k8s client from config path: '%s'", kubeConfigPath)
 	kubeConfig, err := clientcmd.BuildConfigFromFlags("", kubeConfigPath)
@@ -53,3 +61,8 @@ func (kc *Client) ListPods(namespace string) (*v1.PodList, error) {
 	pods, err := kc.client.CoreV1().Pods(namespace).List(metav1.ListOptions{})
 	return pods, errors.Wrapf(err, "unable to list pods in ns '%s'", namespace)
 }
+
+func (kc *Client) ListNodes() (*v1.NodeList, error) {
+	nodes, err := kc.client.CoreV1().Nodes().List(metav1.ListOptions{})
+	return nodes, errors.Wrapf(err, "unable to list nodes")
+}