Add version logging (#817)

* Add more logging

issue #816  add more logging for better debug and information about version auto-detection and fix typo

* Fix typo

* Add more logging

issue #816  add more logging for better debug and information about version auto-detection and fix typo

* tidy logging output

Co-authored-by: Liz Rice <liz@lizrice.com>

* tidy logging output

Co-authored-by: Liz Rice <liz@lizrice.com>

* tidy logging output

Co-authored-by: Liz Rice <liz@lizrice.com>

* tidy logging output

Co-authored-by: Liz Rice <liz@lizrice.com>

* tidy logging output

Co-authored-by: Liz Rice <liz@lizrice.com>

* tidy logging output

Co-authored-by: Liz Rice <liz@lizrice.com>

* tidy logging output

Co-authored-by: Liz Rice <liz@lizrice.com>

* Remove extra logging

Co-authored-by: Liz Rice <liz@lizrice.com>

cmd/kubernetes_version.go

@@ -33,24 +33,28 @@ func (k *KubeVersion) BaseVersion() string {
 }
 
 func getKubeVersionFromRESTAPI() (*KubeVersion, error) {
+	glog.V(2).Info("Try to get version from Rest API")
 	k8sVersionURL := getKubernetesURL()
 	serviceaccount := "/var/run/secrets/kubernetes.io/serviceaccount"
 	cacertfile := fmt.Sprintf("%s/ca.crt", serviceaccount)
 	tokenfile := fmt.Sprintf("%s/token", serviceaccount)
 
-	tlsCert, err := loadCertficate(cacertfile)
+	tlsCert, err := loadCertificate(cacertfile)
 	if err != nil {
+		glog.V(2).Infof("Failed loading certificate Error: %s", err)
 		return nil, err
 	}
 
 	tb, err := ioutil.ReadFile(tokenfile)
 	if err != nil {
+		glog.V(2).Infof("Failed reading token file Error: %s", err)
 		return nil, err
 	}
 	token := strings.TrimSpace(string(tb))
 
 	data, err := getWebDataWithRetry(k8sVersionURL, token, tlsCert)
 	if err != nil {
+		glog.V(2).Infof("Failed to get data Error: %s", err)
 		return nil, err
 	}
 
@@ -143,7 +147,7 @@ func getWebData(srvURL, token string, cacert *tls.Certificate) ([]byte, error) {
 	return ioutil.ReadAll(resp.Body)
 }
 
-func loadCertficate(certFile string) (*tls.Certificate, error) {
+func loadCertificate(certFile string) (*tls.Certificate, error) {
 	cacert, err := ioutil.ReadFile(certFile)
 	if err != nil {
 		return nil, err

cmd/kubernetes_version_test.go

@@ -11,8 +11,8 @@ import (
 	"testing"
 )
 
-func TestLoadCertficate(t *testing.T) {
-	tmp, err := ioutil.TempDir("", "TestFakeLoadCertficate")
+func TestLoadCertificate(t *testing.T) {
+	tmp, err := ioutil.TempDir("", "TestFakeLoadCertificate")
 	if err != nil {
 		t.Fatalf("unable to create temp directory: %v", err)
 	}
@@ -58,7 +58,7 @@ FAjB57z2NcIgJuVpQnGRYtr/JcH2Qdsq8bLtXaojUIWOOqoTDRLYozdMOOQ=
 
 	for id, c := range cases {
 		t.Run(strconv.Itoa(id), func(t *testing.T) {
-			tlsCert, err := loadCertficate(c.file)
+			tlsCert, err := loadCertificate(c.file)
 			if !c.fail {
 				if err != nil {
 					t.Errorf("unexpected error: %v", err)

cmd/util.go

@@ -291,12 +291,15 @@ func getKubeVersion() (*KubeVersion, error) {
 	_, err := exec.LookPath("kubectl")
 
 	if err != nil {
+		glog.V(3).Infof("Error locating kubectl: %s", err)
 		_, err = exec.LookPath("kubelet")
 		if err != nil {
+			glog.V(3).Infof("Error locating kubelet: %s", err)
 			// Search for the kubelet binary all over the filesystem and run the first match to get the kubernetes version
 			cmd := exec.Command("/bin/sh", "-c", "`find / -type f -executable -name kubelet 2>/dev/null | grep -m1 .` --version")
 			out, err := cmd.CombinedOutput()
 			if err == nil {
+				glog.V(3).Infof("Found kubelet and query kubernetes version is: %s", string(out))
 				return getVersionFromKubeletOutput(string(out)), nil
 			}
 
@@ -313,6 +316,7 @@ func getKubeVersionFromKubectl() *KubeVersion {
 	cmd := exec.Command("kubectl", "version", "-o", "json")
 	out, err := cmd.CombinedOutput()
 	if err != nil {
+		glog.V(2).Infof("Failed to query kubectl: %s", err)
 		glog.V(2).Info(err)
 	}
 
@@ -324,6 +328,7 @@ func getKubeVersionFromKubelet() *KubeVersion {
 	out, err := cmd.CombinedOutput()
 
 	if err != nil {
+		glog.V(2).Infof("Failed to query kubelet: %s", err)
 		glog.V(2).Info(err)
 	}
 
@@ -331,7 +336,7 @@ func getKubeVersionFromKubelet() *KubeVersion {
 }
 
 func getVersionFromKubectlOutput(s string) *KubeVersion {
-	glog.V(2).Info(s)
+	glog.V(2).Infof("Kubectl output: %s", s)
 	type versionResult struct {
 		ServerVersion VersionResponse
 	}
@@ -354,7 +359,7 @@ func getVersionFromKubectlOutput(s string) *KubeVersion {
 }
 
 func getVersionFromKubeletOutput(s string) *KubeVersion {
-	glog.V(2).Info(s)
+	glog.V(2).Infof("Kubelet output: %s", s)
 	serverVersionRe := regexp.MustCompile(`Kubernetes v(\d+.\d+)`)
 	subs := serverVersionRe.FindStringSubmatch(s)
 	if len(subs) < 2 {