Merge pull request #1926 from yashvardhan-kukreja/issue-1574/support-…

…for-node-labels-to-config

added: support for adding labels from the config file itself

pkg/apis/config/v1alpha4/types.go

@@ -104,6 +104,9 @@ type Node struct {
 	// If unset a default image will be used, see defaults.Image
 	Image string `yaml:"image,omitempty"`
 
+	// Labels are the labels with which the respective node will be labeled
+	Labels map[string]string `yaml:"labels,omitempty"`
+
 	/* Advanced fields */
 
 	// TODO: cri-like types should be inline instead

pkg/cluster/internal/create/actions/config/config.go

@@ -98,15 +98,42 @@ func (a *Action) Execute(ctx *actions.ActionContext) error {
 		}
 	}
 
+	// Populate the list of control-plane node labels and the list of worker node labels respectively.
+	// controlPlaneLabels is an array of maps (labels, read from config) associated with all the control-plane nodes.
+	// workerLabels is an array of maps (labels, read from config) associated with all the worker nodes.
+	controlPlaneLabels := []map[string]string{}
+	workerLabels := []map[string]string{}
+	for _, node := range ctx.Config.Nodes {
+		if node.Role == config.ControlPlaneRole {
+			controlPlaneLabels = append(controlPlaneLabels, node.Labels)
+		} else if node.Role == config.WorkerRole {
+			workerLabels = append(workerLabels, node.Labels)
+		} else {
+			continue
+		}
+	}
+
+	// hashMapLabelsToCommaSeparatedLabels converts labels in hashmap form to labels in a comma-separated string form like "key1=value1,key2=value2"
+	hashMapLabelsToCommaSeparatedLabels := func(labels map[string]string) string {
+		output := ""
+		for key, value := range labels {
+			output += fmt.Sprintf("%s=%s,", key, value)
+		}
+		return strings.TrimSuffix(output, ",") // remove the last character (comma) in the output string
+	}
+
 	// create the kubeadm join configuration for control plane nodes
 	controlPlanes, err := nodeutils.ControlPlaneNodes(allNodes)
 	if err != nil {
 		return err
 	}
 
-	for _, node := range controlPlanes {
+	for i, node := range controlPlanes {
 		node := node             // capture loop variable
 		configData := configData // copy config data
+		if len(controlPlaneLabels[i]) > 0 {
+			configData.NodeLabels = hashMapLabelsToCommaSeparatedLabels(controlPlaneLabels[i]) // updating the config with the respective labels to be written over the current control-plane node in consideration
+		}
 		fns = append(fns, kubeadmConfigPlusPatches(node, configData))
 	}
 
@@ -117,10 +144,13 @@ func (a *Action) Execute(ctx *actions.ActionContext) error {
 	}
 	if len(workers) > 0 {
 		// create the workers concurrently
-		for _, node := range workers {
+		for i, node := range workers {
 			node := node             // capture loop variable
 			configData := configData // copy config data
 			configData.ControlPlane = false
+			if len(workerLabels[i]) > 0 {
+				configData.NodeLabels = hashMapLabelsToCommaSeparatedLabels(workerLabels[i]) // updating the config with the respective labels to be written over the current worker node in consideration
+			}
 			fns = append(fns, kubeadmConfigPlusPatches(node, configData))
 		}
 	}

pkg/cluster/internal/kubeadm/config.go

@@ -70,6 +70,9 @@ type ConfigData struct {
 	// IPv4 values take precedence over IPv6 by default, if true set IPv6 default values
 	IPv6 bool
 
+	// Labels are the labels, in the format "key1=val1,key2=val2", with which the respective node will be labeled
+	NodeLabels string
+
 	// DerivedConfigData is populated by Derive()
 	// These auto-generated fields are available to Config templates,
 	// but not meant to be set by hand
@@ -326,6 +329,7 @@ nodeRegistration:
     fail-swap-on: "false"
     node-ip: "{{ .NodeAddress }}"
     provider-id: "kind://{{.NodeProvider}}/{{.ClusterName}}/{{.NodeName}}"
+    node-labels: "{{ .NodeLabels }}"
 ---
 # no-op entry that exists solely so it can be patched
 apiVersion: kubeadm.k8s.io/v1beta2
@@ -344,6 +348,7 @@ nodeRegistration:
     fail-swap-on: "false"
     node-ip: "{{ .NodeAddress }}"
     provider-id: "kind://{{.NodeProvider}}/{{.ClusterName}}/{{.NodeName}}"
+    node-labels: "{{ .NodeLabels }}"
 discovery:
   bootstrapToken:
     apiServerEndpoint: "{{ .ControlPlaneEndpoint }}"

pkg/internal/apis/config/convert_v1alpha4.go

@@ -51,6 +51,7 @@ func convertv1alpha4Node(in *v1alpha4.Node, out *Node) {
 	out.Role = NodeRole(in.Role)
 	out.Image = in.Image
 
+	out.Labels = in.Labels
 	out.KubeadmConfigPatches = in.KubeadmConfigPatches
 	out.ExtraMounts = make([]Mount, len(in.ExtraMounts))
 	out.ExtraPortMappings = make([]PortMapping, len(in.ExtraPortMappings))

pkg/internal/apis/config/types.go

@@ -85,6 +85,9 @@ type Node struct {
 	// If unset a default image will be used, see defaults.Image
 	Image string
 
+	// Labels are the labels with which the respective node will be labeled
+	Labels map[string]string
+
 	/* Advanced fields */
 
 	// ExtraMounts describes additional mount points for the node container