Separate ConfigMap templating and creation

This commit factors out the building of a corev1.ConfigMap struct into a separate function, while leaving the logic of determining key parameters, such as the initial cluster, state, etc, as well as sending the request to the k8s API server in the already existing CreateOrUpdate function. This will be useful in the future, when this logic will be moved out of the factory library and into the reconciliation loop.

internal/controller/factory/configmap.go

@@ -19,6 +19,7 @@ package factory
 import (
 	"context"
 	"fmt"
+	"strings"
 
 	etcdaenixiov1alpha1 "github.com/aenix-io/etcd-operator/api/v1alpha1"
 	"github.com/aenix-io/etcd-operator/internal/log"
@@ -39,39 +40,16 @@ func CreateOrUpdateClusterStateConfigMap(
 	rclient client.Client,
 ) error {
 	var err error
-	initialCluster := ""
-	clusterService := fmt.Sprintf("%s.%s.svc:2380", GetHeadlessServiceName(cluster), cluster.Namespace)
-	for i := int32(0); i < *cluster.Spec.Replicas; i++ {
-		if i > 0 {
-			initialCluster += ","
-		}
-		podName := fmt.Sprintf("%s-%d", cluster.Name, i)
-		initialCluster += fmt.Sprintf("%s=https://%s.%s",
-			podName, podName, clusterService,
-		)
-	}
-
-	configMap := &corev1.ConfigMap{
-		ObjectMeta: metav1.ObjectMeta{
-			Namespace: cluster.Namespace,
-			Name:      GetClusterStateConfigMapName(cluster),
-		},
-		Data: map[string]string{
-			"ETCD_INITIAL_CLUSTER_STATE": "new",
-			"ETCD_INITIAL_CLUSTER":       initialCluster,
-			"ETCD_INITIAL_CLUSTER_TOKEN": cluster.Name + "-" + cluster.Namespace,
-		},
+	state := "new"
+	if isEtcdClusterReady(cluster) {
+		state = "existing"
 	}
+	configMap := TemplateClusterStateConfigMap(cluster, state, int(*cluster.Spec.Replicas))
 	ctx, err = contextWithGVK(ctx, configMap, rclient.Scheme())
 	if err != nil {
 		return err
 	}
 
-	if isEtcdClusterReady(cluster) {
-		// update cluster state to existing
-		log.Debug(ctx, "updating cluster state")
-		configMap.Data["ETCD_INITIAL_CLUSTER_STATE"] = "existing"
-	}
 	log.Debug(ctx, "configmap data generated", "data", configMap.Data)
 
 	if err := ctrl.SetControllerReference(cluster, configMap, rclient.Scheme()); err != nil {
@@ -88,3 +66,32 @@ func isEtcdClusterReady(cluster *etcdaenixiov1alpha1.EtcdCluster) bool {
 	return cond != nil && (cond.Reason == string(etcdaenixiov1alpha1.EtcdCondTypeStatefulSetReady) ||
 		cond.Reason == string(etcdaenixiov1alpha1.EtcdCondTypeStatefulSetNotReady))
 }
+func TemplateClusterStateConfigMap(cluster *etcdaenixiov1alpha1.EtcdCluster, state string, replicas int) *corev1.ConfigMap {
+
+	initialClusterMembers := make([]string, replicas)
+	clusterService := fmt.Sprintf("%s.%s.svc:2380", GetHeadlessServiceName(cluster), cluster.Namespace)
+	for i := 0; i < replicas; i++ {
+		podName := fmt.Sprintf("%s-%d", cluster.Name, i)
+		initialClusterMembers[i] = fmt.Sprintf("%s=https://%s.%s",
+			podName, podName, clusterService,
+		)
+	}
+	initialCluster := strings.Join(initialClusterMembers, ",")
+
+	configMap := &corev1.ConfigMap{
+		TypeMeta: metav1.TypeMeta{
+			APIVersion: "v1",
+			Kind:       "ConfigMap",
+		},
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      fmt.Sprintf("%s-cluster-state", cluster.Name),
+			Namespace: cluster.Namespace,
+		},
+		Data: map[string]string{
+			"ETCD_INITIAL_CLUSTER_STATE": state,
+			"ETCD_INITIAL_CLUSTER":       initialCluster,
+			"ETCD_INITIAL_CLUSTER_TOKEN": fmt.Sprintf("%s-%s", cluster.Name, cluster.Namespace),
+		},
+	}
+	return configMap
+}