fix: error on missing CoreDNS version

Author: dkoshkin

pkg/handlers/generic/mutation/coredns/inject.go

@@ -5,6 +5,7 @@ package coredns
 
 import (
 	"context"
+	"errors"
 
 	apiextensionsv1 "k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1"
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
@@ -27,6 +28,10 @@ const (
 	VariableName = "coreDNS"
 )
 
+var ErrDefaultCoreDNSVersionNotFound = errors.New(
+	"could not determine default CoreDNS version based on the Kubernetes version",
+)
+
 type coreDNSPatchHandler struct {
 	variableName      string
 	variableFieldPath []string
@@ -113,7 +118,7 @@ func (h *coreDNSPatchHandler) Mutate(
 					cluster.Spec.Topology.Version,
 				)
 				if !found {
-					log.Info("Default CoreDNS version not found for Kubernetes version")
+					return ErrDefaultCoreDNSVersionNotFound
 				}
 				dns.ImageTag = defaultCoreDNSVersion
 			}

pkg/handlers/generic/mutation/coredns/inject_test.go

@@ -203,6 +203,71 @@ var _ = Describe("Generate CoreDNS patches", func() {
 				},
 			},
 		},
+		{
+			patchTest: capitest.PatchTestDef{
+				Name:            "error if cannot find default CoreDNS version",
+				RequestItem:     request.NewKubeadmControlPlaneTemplateRequestItem(""),
+				ExpectedFailure: true,
+			},
+			cluster: clusterv1.Cluster{
+				ObjectMeta: metav1.ObjectMeta{
+					Name:      "test-cluster",
+					Namespace: request.Namespace,
+					Labels: map[string]string{
+						clusterv1.ProviderNameLabel: "nutanix",
+					},
+				},
+				Spec: clusterv1.ClusterSpec{
+					Topology: &clusterv1.Topology{
+						Version: "1.100.100",
+					},
+				},
+			},
+		},
+		{
+			patchTest: capitest.PatchTestDef{
+				Name: "no error if cannot find default CoreDNS version but variable is set",
+				Vars: []runtimehooksv1.Variable{
+					capitest.VariableWithValue(
+						v1alpha1.ClusterConfigVariableName,
+						v1alpha1.CoreDNS{
+							Image: &v1alpha1.Image{
+								Repository: "my-registry.io/my-org/my-repo",
+								Tag:        "v1.11.3_custom.0",
+							},
+						},
+						v1alpha1.DNSVariableName,
+						VariableName,
+					),
+				},
+				RequestItem: request.NewKubeadmControlPlaneTemplateRequestItem(""),
+				ExpectedPatchMatchers: []capitest.JSONPatchMatcher{{
+					Operation: "add",
+					Path:      "/spec/template/spec/kubeadmConfigSpec/clusterConfiguration",
+					ValueMatcher: gomega.HaveKeyWithValue(
+						"dns",
+						map[string]interface{}{
+							"imageRepository": "my-registry.io/my-org/my-repo",
+							"imageTag":        "v1.11.3_custom.0",
+						},
+					),
+				}},
+			},
+			cluster: clusterv1.Cluster{
+				ObjectMeta: metav1.ObjectMeta{
+					Name:      "test-cluster",
+					Namespace: request.Namespace,
+					Labels: map[string]string{
+						clusterv1.ProviderNameLabel: "nutanix",
+					},
+				},
+				Spec: clusterv1.ClusterSpec{
+					Topology: &clusterv1.Topology{
+						Version: "1.100.100",
+					},
+				},
+			},
+		},
 	}
 
 	// create test node for each case