Kubelet-rkt: Add useful informations for Ops on the Kubelet Host

Create a Systemd SyslogIdentifier inside the [Service]
Create a Systemd Description inside the [Unit]

pkg/kubelet/rkt/rkt.go

@@ -1108,6 +1108,18 @@ func (r *Runtime) getSelinuxContext(opt *v1.SELinuxOptions) (string, error) {
 	return strings.Join(ctx, ":"), nil
 }
 
+// From the generateName or the podName return a basename for improve the logging with the Journal
+// journalctl -t podBaseName
+func constructSyslogIdentifier(generateName string, podName string) string {
+	if (len(generateName) > 1 && generateName[len(generateName) - 1] == '-') {
+		return generateName[0:len(generateName) - 1]
+	} else if (len(generateName) > 0) {
+		return generateName
+	} else {
+		return podName
+	}
+}
+
 // preparePod will:
 //
 // 1. Invoke 'rkt prepare' to prepare the pod, and get the rkt pod uuid.
@@ -1174,6 +1186,9 @@ func (r *Runtime) preparePod(pod *v1.Pod, podIP string, pullSecrets []v1.Secret,
 		// This enables graceful stop.
 		newUnitOption("Service", "KillMode", "mixed"),
 		newUnitOption("Service", "TimeoutStopSec", fmt.Sprintf("%ds", getPodTerminationGracePeriodInSecond(pod))),
+		// Ops helpers
+		newUnitOption("Unit", "Description", pod.Name),
+		newUnitOption("Service", "SyslogIdentifier", constructSyslogIdentifier(pod.GenerateName, pod.Name)),
 		// Track pod info for garbage collection
 		newUnitOption(unitKubernetesSection, unitPodUID, string(pod.UID)),
 		newUnitOption(unitKubernetesSection, unitPodName, pod.Name),

pkg/kubelet/rkt/rkt_test.go

@@ -1952,3 +1952,31 @@ func TestPreparePodArgs(t *testing.T) {
 		assert.Equal(t, testCase.cmd, cmd, fmt.Sprintf("Test case #%d", i))
 	}
 }
+
+func TestConstructSyslogIdentifier(t *testing.T) {
+	testCases := []struct {
+		podName     		string
+		podGenerateName 	string
+		identifier          	string
+	}{
+		{
+			"prometheus-node-exporter-rv90m",
+			"prometheus-node-exporter-",
+			"prometheus-node-exporter",
+		},
+		{
+			"simplepod",
+			"",
+			"simplepod",
+		},
+		{
+			"p",
+			"",
+			"p",
+		},
+	}
+	for i, testCase := range testCases {
+		identifier := constructSyslogIdentifier(testCase.podGenerateName, testCase.podName)
+		assert.Equal(t, testCase.identifier, identifier, fmt.Sprintf("Test case #%d", i))
+	}
+}