Start using klog for logging

Signed-off-by: Ahmet Alp Balkan <[email protected]>

Author: ahmetb

cmd/kubectl-tree/apis.go

@@ -5,7 +5,9 @@ import (
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime/schema"
 	"k8s.io/client-go/discovery"
+	"k8s.io/klog"
 	"strings"
+	"time"
 )
 
 type apiResource struct {
@@ -39,31 +41,39 @@ func fullAPIName(a apiResource) string {
 	return strings.Join([]string{sgv.Resource, sgv.Version, sgv.Group}, ".")
 }
 
-func buildAPILookup(client discovery.DiscoveryInterface) (*resourceMap, error) {
+func findAPIs(client discovery.DiscoveryInterface) (*resourceMap, error) {
+	start := time.Now()
 	resList, err := client.ServerPreferredResources()
 	if err != nil {
 		return nil, fmt.Errorf("failed to fetch api groups from kubernetes: %w", err)
 	}
+	klog.V(2).Infof("queried api discovery in %v", time.Since(start))
+	klog.V(3).Infof("found %d items (groups) in server-preferred APIResourceList", len(resList))
 
 	rm := &resourceMap{
 		m: make(resourceNameLookup),
 	}
 	for _, group := range resList {
+		klog.V(5).Infof("iterating over group %s/%s (%d apis)", group.GroupVersion, group.APIVersion, len(group.APIResources))
 		gv, err := schema.ParseGroupVersion(group.GroupVersion)
 		if err != nil {
 			return nil, fmt.Errorf("%q cannot be parsed into groupversion: %w", group.GroupVersion, err)
 		}
 
 		for _, apiRes := range group.APIResources {
+			klog.V(5).Infof("  api=%s namespaced=%v", apiRes.Name, apiRes.Namespaced)
 			if !contains(apiRes.Verbs, "list") {
+				klog.V(4).Infof("    api (%s) doesn't have required verb, skipping: %v", apiRes.Name, apiRes.Verbs)
 				continue
 			}
 
 			v := apiResource{
 				gv: gv,
 				r:  apiRes,
 			}
-			for _, name := range apiNames(apiRes, gv) {
+			names := apiNames(apiRes, gv)
+			klog.V(6).Infof("names: %s", strings.Join(names, ", "))
+			for _, name := range names {
 				rm.m[name] = append(rm.m[name], v)
 			}
 			rm.list = append(rm.list, v)

cmd/kubectl-tree/query.go

@@ -5,7 +5,9 @@ import (
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
 	"k8s.io/client-go/dynamic"
+	"k8s.io/klog"
 	"sync"
+	"time"
 )
 
 // getAllResources finds all API objects in specified API resources in all namespaces (or non-namespaced).
@@ -14,22 +16,32 @@ func getAllResources(client dynamic.Interface, apis []apiResource) ([]unstructur
 	var wg sync.WaitGroup
 	var out []unstructured.Unstructured
 
+	start := time.Now()
+	klog.V(2).Infof("starting to query %d APIs in concurrently", len(apis))
+
 	var errResult error
 	for _, api := range apis {
 		wg.Add(1)
 		go func(a apiResource) {
 			defer wg.Done()
+			klog.V(4).Infof("[query api] start: %s", a.GroupVersionResource())
 			v, err := queryAPI(client, a)
 			if err != nil {
+				klog.V(4).Infof("[query api] error querying: %s, error=%v", a.GroupVersionResource(), err)
 				errResult = err
 				return
 			}
 			mu.Lock()
 			out = append(out, v...)
 			mu.Unlock()
+			klog.V(4).Infof("[query api]  done: %s, found %d apis", a.GroupVersionResource(), len(v))
 		}(api)
 	}
+
+	klog.V(2).Infof("fired up all goroutines to query APIs")
 	wg.Wait()
+	klog.V(2).Infof("all goroutines have returned in %v", time.Since(start))
+	klog.V(2).Infof("query result: error=%v, objects=%d", errResult, len(out))
 	return out, errResult
 }
 

cmd/kubectl-tree/rootcmd.go

@@ -16,11 +16,14 @@ limitations under the License.
 package main
 
 import (
+	"flag"
 	"fmt"
 	"github.com/spf13/cobra"
+	"github.com/spf13/pflag"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/cli-runtime/pkg/genericclioptions"
 	"k8s.io/client-go/dynamic"
+	"k8s.io/klog"
 	"os"
 	"strings"
 
@@ -55,13 +58,17 @@ func run(_ *cobra.Command, args []string) error {
 	if err != nil {
 		return err
 	}
-	apis, err := buildAPILookup(dc)
+
+	apis, err := findAPIs(dc)
 	if err != nil {
 		return err
 	}
+	klog.V(3).Info("completed querying APIs list")
 
 	kind, name := args[0], args[1]
+	klog.V(3).Infof("parsed kind=%v name=%v", kind, name)
 	apiRes := apis.lookup(kind)
+	klog.V(5).Infof("kind matches=%v", apiRes)
 	if len(apiRes) == 0 {
 		return fmt.Errorf("could not find api kind %q", kind)
 	} else if len(apiRes) > 1 {
@@ -82,25 +89,47 @@ func run(_ *cobra.Command, args []string) error {
 		return fmt.Errorf("failed to get %s/%s: %w", kind, name, err)
 	}
 
+	klog.V(5).Infof("target parent object: %#v", obj)
+
+	klog.V(2).Infof("querying all api objects")
 	apiObjects, err := getAllResources(dyn, apis.resources())
 	if err != nil {
 		return fmt.Errorf("error while querying api objects: %w", err)
 	}
+	klog.V(2).Infof("found total %d api objects", len(apiObjects))
 
 	objs := newObjectDirectory(apiObjects)
 	if len(objs.ownership[obj.GetUID()]) == 0 {
 		fmt.Println("No resources are owned by the specified object through ownerReferences.")
 		return nil
 	}
 	treeView(os.Stderr, objs, *obj)
+	klog.V(2).Infof("done printing tree view")
 	return nil
 }
 
-func main() {
+func init() {
+	klog.InitFlags(nil)
+	pflag.CommandLine.AddGoFlagSet(flag.CommandLine)
+
+	// hide all glog flags except for -v
+	flag.CommandLine.VisitAll(func(f *flag.Flag) {
+		if f.Name != "v" {
+			pflag.Lookup(f.Name).Hidden = true
+		}
+	})
+
 	cf = genericclioptions.NewConfigFlags(true)
 	cf.AddFlags(rootCmd.Flags())
-	if err := rootCmd.Execute(); err != nil {
+	if err := flag.Set("logtostderr", "true"); err != nil {
+		fmt.Fprintf(os.Stderr, "failed to set logtostderr flag: %v\n", err)
 		os.Exit(1)
 	}
 }
 
+func main() {
+	defer klog.Flush()
+	if err := rootCmd.Execute(); err != nil {
+		os.Exit(1)
+	}
+}

cmd/kubectl-tree/status.go

@@ -1,13 +1,17 @@
 package main
 
 import (
+	"encoding/json"
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+	"k8s.io/klog"
 )
 
 type ReadyStatus string // True False Unknown or ""
 type Reason string
 
 func extractStatus(obj unstructured.Unstructured) (ReadyStatus, Reason) {
+	jsonVal, _ := json.Marshal(obj.Object["status"])
+	klog.V(6).Infof("status for object=%s/%s: %s", obj.GetKind(), obj.GetName(), string(jsonVal))
 	statusF, ok := obj.Object["status"]
 	if !ok {
 		return "", ""

go.mod

@@ -15,6 +15,7 @@ require (
 	github.com/mattn/go-isatty v0.0.11 // indirect
 	github.com/mattn/go-runewidth v0.0.7 // indirect
 	github.com/spf13/cobra v0.0.5
+	github.com/spf13/pflag v1.0.5
 	golang.org/x/crypto v0.0.0-20191206172530-e9b2fee46413 // indirect
 	golang.org/x/net v0.0.0-20191209160850-c0dbc17a3553 // indirect
 	golang.org/x/oauth2 v0.0.0-20191202225959-858c2ad4c8b6 // indirect
@@ -25,5 +26,6 @@ require (
 	k8s.io/apimachinery v0.17.0
 	k8s.io/cli-runtime v0.17.0
 	k8s.io/client-go v0.17.0
+	k8s.io/klog v1.0.0
 	k8s.io/utils v0.0.0-20191218082557-f07c713de883 // indirect
 )