ctop/connector/kubernetes.go

package connector

import (
	"os"
	"path/filepath"
	"sync"

	"github.com/bcicen/ctop/connector/collector"
	"github.com/bcicen/ctop/connector/manager"
	"github.com/bcicen/ctop/container"
	api "github.com/fsouza/go-dockerclient"
	"k8s.io/api/core/v1"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/client-go/kubernetes"
	"k8s.io/client-go/tools/clientcmd"
)

func init() { enabled["kubernetes"] = NewKubernetes }

var namespace = "akozlenkov"

type Kubernetes struct {
	clientset    *kubernetes.Clientset
	containers   map[string]*container.Container
	needsRefresh chan string // container IDs requiring refresh
	lock         sync.RWMutex
}

func NewKubernetes() Connector {
	var kubeconfig string
	//if home := homeDir(); home != "" {
	//	kubeconfig = flag.String("kubeconfig", filepath.Join(home, ".kube", "config"), "(optional) absolute path to the kubeconfig file")
	//} else {
	//	kubeconfig = flag.String("kubeconfig", "", "absolute path to the kubeconfig file")
	//}
	//flag.Parse()
	kubeconfig = filepath.Join(homeDir(), ".kube", "config")

	// use the current context in kubeconfig
	config, err := clientcmd.BuildConfigFromFlags("", kubeconfig)
	if err != nil {
		log.Error(err.Error())
		return nil
	}

	// create the clientset
	clientset, err := kubernetes.NewForConfig(config)
	if err != nil {
		log.Error(err.Error())
		return nil
	}

	// init docker client
	k := &Kubernetes{
		clientset:    clientset,
		containers:   make(map[string]*container.Container),
		needsRefresh: make(chan string, 60),
		lock:         sync.RWMutex{},
	}
	go k.Loop()
	k.refreshAll()
	return k
}

func (k *Kubernetes) Loop() {
	for id := range k.needsRefresh {
		c := k.MustGet(id)
		k.refresh(c)
	}
	//log.Debug(">>>>>>1")
	//for {
	//	log.Debug(">>>>>>2")
	//	pods, err := k.clientset.CoreV1().Pods("").List(metav1.ListOptions{})
	//	if err != nil {
	//		panic(err.Error())
	//	}
	//	log.Debugf("There are %d pods in the cluster\n", len(pods.Items))

	//	// Examples for error handling:
	//	// - Use helper functions like e.g. errors.IsNotFound()
	//	// - And/or cast to StatusError and use its properties like e.g. ErrStatus.Message
	//	namespace := "akozlenkov"
	//	pod := "example-xxxxx"
	//	_, err = k.clientset.CoreV1().Pods(namespace).Get(pod, metav1.GetOptions{})
	//	if errors.IsNotFound(err) {
	//		log.Debugf("Pod %s in namespace %s not found\n", pod, namespace)
	//	} else if statusError, isStatus := err.(*errors.StatusError); isStatus {
	//		log.Debugf("Error getting pod %s in namespace %s: %v\n",
	//			pod, namespace, statusError.ErrStatus.Message)
	//	} else if err != nil {
	//		panic(err.Error())
	//	} else {
	//		log.Debugf("Found pod %s in namespace %s\n", pod, namespace)
	//	}

	//	time.Sleep(10 * time.Second)
	//}
}

// Get a single container, creating one anew if not existing
func (k *Kubernetes) MustGet(name string) *container.Container {
	c, ok := k.Get(name)
	// append container struct for new containers
	if !ok {
		// create collector
		collector := collector.NewKubernetes(k.clientset, name)
		// create manager
		manager := manager.NewKubernetes(k.clientset, name)
		// create container
		c = container.New(name, collector, manager)
		k.lock.Lock()
		k.containers[name] = c
		k.lock.Unlock()
	}
	return c
}

func (k *Kubernetes) refresh(c *container.Container) {
	insp := k.inspect(c.Id)
	// remove container if no longer exists
	if insp == nil {
		k.delByID(c.Id)
		return
	}
	c.SetMeta("name", insp.Name)
	c.SetMeta("image", "stub")
	c.SetMeta("IPs", "stub")
	c.SetMeta("ports", "stub")
	c.SetMeta("created", "stub")
	c.SetMeta("health", "stub")
	c.SetMeta("[ENV-VAR]", "stub")
	c.SetState("stub")
}

func (k *Kubernetes) inspect(id string) *v1.Pod {
	p, err := k.clientset.CoreV1().Pods(namespace).Get(id, metav1.GetOptions{})
	if err != nil {
		if _, ok := err.(*api.NoSuchContainer); !ok {
			log.Errorf(err.Error())
		}
	}
	return p
}

// Remove containers by ID
func (k *Kubernetes) delByID(name string) {
	k.lock.Lock()
	delete(k.containers, name)
	k.lock.Unlock()
	log.Infof("removed dead container: %s", name)
}

func (k *Kubernetes) Get(name string) (c *container.Container, ok bool) {
	k.lock.Lock()
	c, ok = k.containers[name]
	k.lock.Unlock()
	return
}

// Mark all container IDs for refresh
func (k *Kubernetes) refreshAll() {
	allPods, err := k.clientset.CoreV1().Pods(namespace).List(metav1.ListOptions{})
	if err != nil {
		log.Error(err.Error())
		return
	}

	for _, pod := range allPods.Items {
		c := k.MustGet(pod.Name)
		c.SetMeta("name", pod.Name)
		if pod.Initializers != nil && pod.Initializers.Result != nil {
			c.SetState(pod.Initializers.Result.Status)
		}
		k.needsRefresh <- c.Id
	}
}

func (k *Kubernetes) All() (containers container.Containers) {
	k.lock.Lock()
	for _, c := range k.containers {
		containers = append(containers, c)
	}

	containers.Sort()
	containers.Filter()
	k.lock.Unlock()
	return containers
}

func homeDir() string {
	if h := os.Getenv("HOME"); h != "" {
		return h
	}
	return os.Getenv("USERPROFILE") // windows
}