Another code refactor

This project has seen its use of several framework for both UI and
the Kubernetes client controller. This time, going back to simple
informer model with no controller framework.  This approach seems
simpler and works well with the UI without the complication of full
controller kit (like controller-runtime).

This refactor also updates the way the program works by implementing
the ability to display either usage metrics (from Metrics Server) or
request/limit resource metrics from the API server. That way, the UI
is always functional regardless of how the cluster is setup.

application/app_ctrl.go

@@ -74,22 +74,22 @@ func (app *Application) GetStopChan() <-chan struct{} {
 	return app.stopCh
 }
 
-// ShowBanner displays a welcome banner
 func (app *Application) WelcomeBanner() {
 	fmt.Println(`
- _    _              
-| | _| |_ ___  _ __  
-| |/ / __/ _ \| '_ \ 
+ _    _ 
+| | _| |_ ___  _ __
+| |/ / __/ _ \| '_ \
 |   <| || (_) | |_) |
-|_|\_\\__\___/| .__/ 
+|_|\_\\__\___/| .__/
               |_|`)
 	fmt.Println("Version 0.1.0-alpha.1")
 }
 
-func (app *Application) setup() error {
+func (app *Application) setup(ctx context.Context) error {
 	// setup each page panel
 	for _, page := range app.pages {
-		if err := page.Panel.Run(); err != nil {
+		// TODO propagate context to panel run
+		if err := page.Panel.Run(ctx); err != nil {
 			return fmt.Errorf("init failed: page %s: %s", page.Title, err)
 		}
 	}
@@ -99,15 +99,15 @@ func (app *Application) setup() error {
 
 	var hdr strings.Builder
 	hdr.WriteString("%c [green]API server: [white]%s [green]namespace: [white]%s [green] metrics:")
-	if err := app.k8sClient.AssertMetricsAvailable(); err != nil {
+	if err := app.GetK8sClient().AssertMetricsAvailable(); err != nil {
 		hdr.WriteString(" [red]not connected")
 	} else {
 		hdr.WriteString(" [white]connected")
 	}
 
 	app.panel.DrawHeader(fmt.Sprintf(
 		hdr.String(),
-		ui.Icons.Rocket, app.k8sClient.Config().Host, app.k8sClient.Namespace(),
+		ui.Icons.Rocket, app.GetK8sClient().Config().Host, app.k8sClient.Namespace(),
 	))
 
 	app.panel.DrawFooter(app.getPageTitles()[app.visibleView])
@@ -147,7 +147,7 @@ func (app *Application) setup() error {
 func (app *Application) Run(ctx context.Context) error {
 
 	// setup application UI
-	if err := app.setup(); err != nil {
+	if err := app.setup(ctx); err != nil {
 		return err
 	}
 

go.mod

@@ -1,14 +1,48 @@
 module github.com/vladimirvivien/ktop
 
 require (
-	github.com/gdamore/tcell v1.1.2
-	github.com/gdamore/tcell/v2 v2.1.0
-	github.com/rivo/tview v0.0.0-20201204190810-5406288b8e4e
-	k8s.io/api v0.20.0
-	k8s.io/apimachinery v0.20.1
-	k8s.io/client-go v0.20.0
+	github.com/gdamore/tcell/v2 v2.4.1-0.20210905002822-f057f0a857a1
+	github.com/rivo/tview v0.0.0-20211202162923-2a6de950f73b
+	k8s.io/api v0.23.1
+	k8s.io/apimachinery v0.23.1
+	k8s.io/client-go v0.23.1
 	k8s.io/metrics v0.19.0
-	sigs.k8s.io/controller-runtime v0.7.0
 )
 
-go 1.15
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/gdamore/encoding v1.0.0 // indirect
+	github.com/go-logr/logr v1.2.0 // indirect
+	github.com/gogo/protobuf v1.3.2 // indirect
+	github.com/golang/protobuf v1.5.2 // indirect
+	github.com/google/go-cmp v0.5.5 // indirect
+	github.com/google/gofuzz v1.1.0 // indirect
+	github.com/googleapis/gnostic v0.5.5 // indirect
+	github.com/imdario/mergo v0.3.5 // indirect
+	github.com/json-iterator/go v1.1.12 // indirect
+	github.com/lucasb-eyer/go-colorful v1.2.0 // indirect
+	github.com/mattn/go-runewidth v0.0.13 // indirect
+	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
+	github.com/modern-go/reflect2 v1.0.2 // indirect
+	github.com/rivo/uniseg v0.2.0 // indirect
+	github.com/spf13/pflag v1.0.5 // indirect
+	golang.org/x/net v0.0.0-20211209124913-491a49abca63 // indirect
+	golang.org/x/oauth2 v0.0.0-20210819190943-2bc19b11175f // indirect
+	golang.org/x/sys v0.0.0-20210831042530-f4d43177bf5e // indirect
+	golang.org/x/term v0.0.0-20210615171337-6886f2dfbf5b // indirect
+	golang.org/x/text v0.3.7 // indirect
+	golang.org/x/time v0.0.0-20210723032227-1f47c861a9ac // indirect
+	google.golang.org/appengine v1.6.7 // indirect
+	google.golang.org/protobuf v1.27.1 // indirect
+	gopkg.in/inf.v0 v0.9.1 // indirect
+	gopkg.in/yaml.v2 v2.4.0 // indirect
+	gopkg.in/yaml.v3 v3.0.0-20210107192922-496545a6307b // indirect
+	k8s.io/klog/v2 v2.30.0 // indirect
+	k8s.io/kube-openapi v0.0.0-20211115234752-e816edb12b65 // indirect
+	k8s.io/utils v0.0.0-20210930125809-cb0fa318a74b // indirect
+	sigs.k8s.io/json v0.0.0-20211020170558-c049b76a60c6 // indirect
+	sigs.k8s.io/structured-merge-diff/v4 v4.1.2 // indirect
+	sigs.k8s.io/yaml v1.2.0 // indirect
+)
+
+go 1.17

hack/kind-config.yaml

@@ -1,5 +1,5 @@
 kind: Cluster
-apiVersion: kind.sigs.k8s.io/v1alpha3
+apiVersion: kind.x-k8s.io/v1alpha4 
 nodes:
 - role: control-plane
 - role: worker

hack/metrics-server.yaml

@@ -52,7 +52,7 @@ subjects:
   name: metrics-server
   namespace: kube-system
 ---
-apiVersion: apiregistration.k8s.io/v1beta1
+apiVersion: apiregistration.k8s.io/v1
 kind: APIService
 metadata:
   name: v1beta1.metrics.k8s.io
@@ -96,15 +96,18 @@ spec:
         emptyDir: {}
       containers:
       - name: metrics-server
-        image: k8s.gcr.io/metrics-server/metrics-server:v0.3.7
+        image: gcr.io/k8s-staging-metrics-server/metrics-server:master
         imagePullPolicy: IfNotPresent
         args:
           - --cert-dir=/tmp
-          - --secure-port=4443
+          - --secure-port=443
+          - --kubelet-preferred-address-types=InternalIP,ExternalIP,Hostname
+          - --kubelet-use-node-status-port
+          - --metric-resolution=15s
           - --kubelet-insecure-tls
         ports:
         - name: main-port
-          containerPort: 4443
+          containerPort: 443
           protocol: TCP
         securityContext:
           readOnlyRootFilesystem: true

hack/minikube.sh

@@ -1,7 +1,7 @@
 #!/bin/sh
 
-minikube start --memory=2192 --cpus=2 \
-  --kubernetes-version=v1.20.0 \
-  --vm-driver=docker \
+minikube start --memory=4096 --cpus=2 \
+  --kubernetes-version=v1.23.1 \
+  --vm-driver=hyperkit \
   --bootstrapper=kubeadm \
   --extra-config=apiserver.enable-admission-plugins="LimitRanger,NamespaceExists,NamespaceLifecycle,ResourceQuota,ServiceAccount,DefaultStorageClass,MutatingAdmissionWebhook"

hack/persistent-volume-local.yaml

@@ -0,0 +1,14 @@
+apiVersion: v1
+kind: PersistentVolume
+metadata:
+  name: local-pv-volume
+  labels:
+    type: local
+spec:
+  storageClassName: local-storage
+  capacity:
+    storage: 1Gi
+  accessModes:
+    - ReadWriteOnce
+  hostPath:
+    path: "/mnt/data"

k8s/client.go

@@ -3,9 +3,9 @@ package k8s
 import (
 	"context"
 	"fmt"
+	"time"
 
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
-	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/runtime/schema"
 	"k8s.io/client-go/discovery"
 	"k8s.io/client-go/dynamic"
@@ -15,22 +15,15 @@ import (
 	metricsclient "k8s.io/metrics/pkg/client/clientset/versioned"
 )
 
-var (
-	NodesResource = schema.GroupVersionResource{Group: "", Version: "v1", Resource: "nodes"}
-	PodsResource  = schema.GroupVersionResource{Group: "", Version: "v1", Resource: "pods"}
-)
-
-type ListFunc func(ctx context.Context, namespace string, list runtime.Object) error
-
 type Client struct {
 	namespace        string
 	config           *restclient.Config
 	dynaClient       dynamic.Interface
 	discoClient      *discovery.DiscoveryClient
 	metricsClient    *metricsclient.Clientset
 	metricsAvailable bool
-	nodeWatcher      *NodeWatcher
-	podWatcher       *PodWatcher
+	refreshTimeout   time.Duration
+	controller *Controller
 }
 
 func New(ctx context.Context, kubeconfig, kubectx, namespace string) (*Client, error) {
@@ -61,16 +54,7 @@ func New(ctx context.Context, kubeconfig, kubectx, namespace string) (*Client, e
 		discoClient:   disco,
 		metricsClient: metrics,
 	}
-
-	client.nodeWatcher = NewNodeWatcher(client)
-	if err := client.nodeWatcher.Start(ctx); err != nil {
-		return nil, err
-	}
-	client.podWatcher = NewPodWatcher(client)
-	if err := client.podWatcher.Start(ctx); err != nil {
-		return nil, err
-	}
-
+	client.controller = newController(client)
 	return client, nil
 }
 
@@ -138,10 +122,6 @@ func (k8s *Client) GetPodMetrics(ctx context.Context, podName string) (*metricsV
 	return metrics, nil
 }
 
-func (k8s *Client) AddNodeListFunc(f ListFunc) {
-	k8s.nodeWatcher.AddNodeListFunc(f)
-}
-
-func (k8s *Client) AddPodListFunc(f ListFunc) {
-	k8s.podWatcher.AddPodListFunc(f)
-}
+func (k8s *Client) Controller() *Controller {
+	return k8s.controller
+}

k8s/client_controller.go

@@ -0,0 +1,103 @@
+package k8s
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"time"
+
+	"github.com/vladimirvivien/ktop/views/model"
+	appsV1 "k8s.io/api/apps/v1"
+	batchV1 "k8s.io/api/batch/v1"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/client-go/dynamic/dynamicinformer"
+	"k8s.io/client-go/informers"
+)
+
+var (
+	GVRs = map[string]schema.GroupVersionResource{
+		"nodes":                  {Group: "", Version: "v1", Resource: "nodes"},
+		"namespaces":             {Group: "", Version: "v1", Resource: "namespaces"},
+		"pods":                   {Group: "", Version: "v1", Resource: "pods"},
+		"persistentvolumeclaims": {Group: "", Version: "v1", Resource: "persistentvolumeclaims"},
+		"deployments":            {Group: appsV1.GroupName, Version: "v1", Resource: "deployments"},
+		"daemonsets":             {Group: appsV1.GroupName, Version: "v1", Resource: "daemonsets"},
+		"replicasets":            {Group: appsV1.GroupName, Version: "v1", Resource: "replicasets"},
+		"statefulsets":           {Group: appsV1.GroupName, Version: "v1", Resource: "statefulsets"},
+		"jobs":                   {Group: batchV1.GroupName, Version: "v1", Resource: "jobs"},
+		"cronjobs":               {Group: batchV1.GroupName, Version: "v1", Resource: "cronjobs"},
+	}
+)
+
+type RefreshNodesFunc func(ctx context.Context, items []model.NodeModel) error
+type RefreshPodsFunc func(ctx context.Context, items []model.PodModel) error
+type RefreshSummaryFunc func(ctx context.Context, items model.ClusterSummary) error
+
+type Controller struct {
+	client            *Client
+	namespaceInformer informers.GenericInformer
+	nodeInformer      informers.GenericInformer
+	nodeRefreshFunc   RefreshNodesFunc
+	podInformer       informers.GenericInformer
+	podRefreshFunc    RefreshPodsFunc
+
+	deploymentInformer  informers.GenericInformer
+	daemonSetInformer   informers.GenericInformer
+	replicaSetInformer  informers.GenericInformer
+	statefulSetInformer informers.GenericInformer
+
+	jobInformer     informers.GenericInformer
+	cronJobInformer informers.GenericInformer
+
+	pvcInformer        informers.GenericInformer
+	summaryRefreshFunc RefreshSummaryFunc
+}
+
+func newController(client *Client) *Controller {
+	ctrl := &Controller{client: client}
+	return ctrl
+}
+
+func (c *Controller) SetNodeRefreshFunc(fn RefreshNodesFunc) *Controller {
+	c.nodeRefreshFunc = fn
+	return c
+}
+func (c *Controller) SetPodRefreshFunc(fn RefreshPodsFunc) *Controller {
+	c.podRefreshFunc = fn
+	return c
+}
+
+func (c *Controller) SetClusterSummaryRefreshFunc(fn RefreshSummaryFunc) *Controller {
+	c.summaryRefreshFunc = fn
+	return c
+}
+
+func (c *Controller) Start(ctx context.Context, resync time.Duration) error {
+	if ctx == nil {
+		return errors.New("context cannot be nil")
+	}
+	factory := dynamicinformer.NewDynamicSharedInformerFactory(c.client.dynaClient, resync)
+	c.namespaceInformer = factory.ForResource(GVRs["namespaces"])
+	c.nodeInformer = factory.ForResource(GVRs["nodes"])
+	c.podInformer = factory.ForResource(GVRs["pods"])
+	c.deploymentInformer = factory.ForResource(GVRs["deployments"])
+	c.daemonSetInformer = factory.ForResource(GVRs["daemonsets"])
+	c.replicaSetInformer = factory.ForResource(GVRs["replicasets"])
+	c.statefulSetInformer = factory.ForResource(GVRs["statefulsets"])
+	c.jobInformer = factory.ForResource(GVRs["jobs"])
+	c.cronJobInformer = factory.ForResource(GVRs["cronjobs"])
+	c.pvcInformer = factory.ForResource(GVRs["persistentvolumeclaims"])
+	//c.installHandler(ctx, c.pvcInformer, c.pvcRefreshFunc)
+
+	factory.Start(ctx.Done())
+	for name, gvr := range GVRs {
+		if synced := factory.WaitForCacheSync(ctx.Done()); !synced[gvr] {
+			return fmt.Errorf("resource not synced: %s", name)
+		}
+	}
+	c.setupSummaryHandler(ctx, c.summaryRefreshFunc)
+	c.setupNodeHandler(ctx, c.nodeRefreshFunc)
+	c.installPodsHandler(ctx, c.podRefreshFunc)
+
+	return nil
+}