Update endpoint IP selection order based on address type found (#61)

Signed-off-by: Rahul Ganesh <rahulgab@amazon.com>
Co-authored-by: Rahul Ganesh <rahulgab@amazon.com>

controllers/helpers.go

@@ -81,7 +81,6 @@ func (r *EtcdadmClusterReconciler) cloneConfigsAndGenerateMachine(ctx context.Co
 		ClusterName: cluster.Name,
 		Labels:      EtcdLabelsForCluster(cluster.Name, ec.Name),
 	})
-
 	if err != nil {
 		return ctrl.Result{}, fmt.Errorf("error cloning infrastructure template for etcd machine: %v", err)
 	}
@@ -158,24 +157,34 @@ func (r *EtcdadmClusterReconciler) generateMachine(ctx context.Context, ec *etcd
 }
 
 func getEtcdMachineAddress(machine *clusterv1.Machine) string {
-	var foundAddress bool
-	var machineAddress string
+	var internalIP, internalDNS, externalIP, externalDNS string
+
+	// Check and record all different address types set for the machine and return later according to precedence.
 	for _, address := range machine.Status.Addresses {
-		if address.Type == clusterv1.MachineInternalIP || address.Type == clusterv1.MachineInternalDNS {
-			machineAddress = address.Address
-			foundAddress = true
-			break
+		switch address.Type {
+		case clusterv1.MachineInternalIP:
+			internalIP = address.Address
+		case clusterv1.MachineInternalDNS:
+			internalDNS = address.Address
+		case clusterv1.MachineExternalIP:
+			externalIP = address.Address
+		case clusterv1.MachineExternalDNS:
+			externalDNS = address.Address
 		}
 	}
-	for _, address := range machine.Status.Addresses {
-		if !foundAddress {
-			if address.Type == clusterv1.MachineExternalIP || address.Type == clusterv1.MachineExternalDNS {
-				machineAddress = address.Address
-				break
-			}
-		}
+
+	// The order of these checks determines the precedence of the address to use
+	if externalDNS != "" {
+		return externalDNS
+	} else if externalIP != "" {
+		return externalIP
+	} else if internalDNS != "" {
+		return internalDNS
+	} else if internalIP != "" {
+		return internalIP
 	}
-	return machineAddress
+
+	return ""
 }
 
 func getMemberClientURL(address string) string {

controllers/helpers_test.go

@@ -0,0 +1,92 @@
+package controllers
+
+import (
+	"testing"
+
+	. "github.com/onsi/gomega"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	clusterv1 "sigs.k8s.io/cluster-api/api/v1beta1"
+)
+
+func TestGetEtcdMachineAddress(t *testing.T) {
+	g := NewWithT(t)
+	type test struct {
+		machine        clusterv1.Machine
+		AvailAddrTypes clusterv1.MachineAddresses
+		wantAddr       string
+	}
+
+	capiMachine := clusterv1.Machine{
+		ObjectMeta: metav1.ObjectMeta{
+			Name: "machine",
+		},
+		Spec: clusterv1.MachineSpec{
+			ClusterName: "test-cluster",
+		},
+		Status: clusterv1.MachineStatus{},
+	}
+	tests := []test{
+		{
+			machine: capiMachine,
+			AvailAddrTypes: clusterv1.MachineAddresses{
+				clusterv1.MachineAddress{
+					Type:    clusterv1.MachineInternalIP,
+					Address: "1.1.1.1",
+				}, clusterv1.MachineAddress{
+					Type:    clusterv1.MachineExternalIP,
+					Address: "2.2.2.2",
+				},
+			},
+			wantAddr: "2.2.2.2",
+		}, {
+			machine: capiMachine,
+			AvailAddrTypes: []clusterv1.MachineAddress{
+				{
+					Type:    clusterv1.MachineInternalDNS,
+					Address: "1.1.1.1",
+				}, {
+					Type:    clusterv1.MachineExternalIP,
+					Address: "2.2.2.2",
+				},
+			},
+			wantAddr: "2.2.2.2",
+		}, {
+			machine: capiMachine,
+			AvailAddrTypes: []clusterv1.MachineAddress{
+				{
+					Type:    clusterv1.MachineInternalIP,
+					Address: "1.1.1.1",
+				}, {
+					Type:    clusterv1.MachineInternalDNS,
+					Address: "2.2.2.2",
+				},
+			},
+			wantAddr: "2.2.2.2",
+		}, {
+			machine: capiMachine,
+			AvailAddrTypes: []clusterv1.MachineAddress{
+				{
+					Type:    clusterv1.MachineExternalDNS,
+					Address: "1.1.1.1",
+				}, {
+					Type:    clusterv1.MachineInternalDNS,
+					Address: "2.2.2.2",
+				},
+			},
+			wantAddr: "1.1.1.1",
+		}, {
+			machine: capiMachine,
+			AvailAddrTypes: []clusterv1.MachineAddress{
+				{
+					Type:    clusterv1.MachineHostName,
+					Address: "1.1.1.1",
+				},
+			},
+			wantAddr: "",
+		},
+	}
+	for _, tc := range tests {
+		capiMachine.Status.Addresses = tc.AvailAddrTypes
+		g.Expect(getEtcdMachineAddress(&capiMachine)).To(Equal(tc.wantAddr))
+	}
+}