kubectl: show node label if defined

We are moving towards marking master nodes as tainted, and not necessarily unschedulable. Further now we encourage users to taint nodes, marking them unschedulable. Thus the reliance on "Unschedulable" is not really a great indicator for the master. Instead, recognize the existing node 'role' markers, and surface them where Unschedulable is (in the status). We recognize: * a kubernetes.io/role label * a kubeadm.alpha.kubernetes.io/role label * a taint with Key 'dedicated' Fix kubernetes#33533
justinsb · Oct 31, 2016 · fbd0cbe · fbd0cbe
1 parent 8ca348a
commit fbd0cbe
Show file tree

Hide file tree

Showing 2 changed files with 91 additions and 0 deletions.
diff --git a/pkg/kubectl/resource_printer.go b/pkg/kubectl/resource_printer.go
@@ -1476,6 +1476,9 @@ func printNode(node *api.Node, w io.Writer, options PrintOptions) error {
 	if node.Spec.Unschedulable {
 		status = append(status, "SchedulingDisabled")
 	}
+	if role := findNodeRole(node); role != "" {
+		status = append(status, role)
+	}
 
 	if _, err := fmt.Fprintf(w, "%s\t%s\t%s", name, strings.Join(status, ","), translateTimestamp(node.CreationTimestamp)); err != nil {
 		return err
@@ -1505,6 +1508,34 @@ func getNodeExternalIP(node *api.Node) string {
 	return "<none>"
 }
 
+// findNodeRole returns the role of a given node, or "" if none found.
+// The role is determined by looking in order for:
+// * a kubernetes.io/role label
+// * a kubeadm.alpha.kubernetes.io/role label
+// * a taint with Key 'dedicated'
+// If no role is found, ("") is returned
+func findNodeRole(node *api.Node) string {
+	if role := node.Labels["kubernetes.io/role"]; role != "" {
+		return role
+	}
+	if role := node.Labels["kubeadm.alpha.kubernetes.io/role"]; role != "" {
+		return role
+	}
+
+	taints, err := api.GetTaintsFromNodeAnnotations(node.Annotations)
+	if err != nil {
+		glog.Warningf("error parsing node taints for node %q: %v", node.Name, err)
+	} else {
+		for _, taint := range taints {
+			if taint.Key == "dedicated" {
+				return taint.Value
+			}
+		}
+	}
+	// No role found
+	return ""
+}
+
 func printNodeList(list *api.NodeList, w io.Writer, options PrintOptions) error {
 	for _, node := range list.Items {
 		if err := printNode(&node, w, options); err != nil {

diff --git a/pkg/kubectl/resource_printer_test.go b/pkg/kubectl/resource_printer_test.go
@@ -678,6 +678,66 @@ func TestPrintNodeStatus(t *testing.T) {
 			},
 			status: "Unknown,SchedulingDisabled",
 		},
+		{
+			node: api.Node{
+				ObjectMeta: api.ObjectMeta{
+					Name:   "foo10",
+					Labels: map[string]string{"kubernetes.io/role": "master"},
+				},
+				Status: api.NodeStatus{Conditions: []api.NodeCondition{{Type: api.NodeReady, Status: api.ConditionTrue}}},
+			},
+			status: "Ready,master",
+		},
+		{
+			node: api.Node{
+				ObjectMeta: api.ObjectMeta{
+					Name:   "foo11",
+					Labels: map[string]string{"kubernetes.io/role": "node"},
+				},
+				Status: api.NodeStatus{Conditions: []api.NodeCondition{{Type: api.NodeReady, Status: api.ConditionTrue}}},
+			},
+			status: "Ready,node",
+		},
+		{
+			node: api.Node{
+				ObjectMeta: api.ObjectMeta{
+					Name:   "foo12",
+					Labels: map[string]string{"kubeadm.alpha.kubernetes.io/role": "node"},
+				},
+				Status: api.NodeStatus{Conditions: []api.NodeCondition{{Type: api.NodeReady, Status: api.ConditionTrue}}},
+			},
+			status: "Ready,node",
+		},
+		{
+			node: api.Node{
+				ObjectMeta: api.ObjectMeta{
+					Name:        "foo13",
+					Annotations: map[string]string{"scheduler.alpha.kubernetes.io/taints": "[{\"key\":\"dedicated\",\"value\":\"master\",\"effect\":\"NoSchedule\"}]"},
+				},
+				Status: api.NodeStatus{Conditions: []api.NodeCondition{{Type: api.NodeReady, Status: api.ConditionTrue}}},
+			},
+			status: "Ready,master",
+		},
+		{
+			node: api.Node{
+				ObjectMeta: api.ObjectMeta{
+					Name:        "foo14",
+					Annotations: map[string]string{"scheduler.alpha.kubernetes.io/taints": "[{\"key\":\"somethingelse\",\"value\":\"master\",\"effect\":\"NoSchedule\"}]"},
+				},
+				Status: api.NodeStatus{Conditions: []api.NodeCondition{{Type: api.NodeReady, Status: api.ConditionTrue}}},
+			},
+			status: "Ready",
+		},
+		{
+			node: api.Node{
+				ObjectMeta: api.ObjectMeta{
+					Name:        "foo15",
+					Annotations: map[string]string{"scheduler.alpha.kubernetes.io/taints": "unparseable"},
+				},
+				Status: api.NodeStatus{Conditions: []api.NodeCondition{{Type: api.NodeReady, Status: api.ConditionTrue}}},
+			},
+			status: "Ready",
+		},
 	}
 
 	for _, test := range table {