Use the MedusaConfiguration API when creating Medusa configuration

CHANGELOG/CHANGELOG-1.12.md

@@ -15,6 +15,7 @@ When cutting a new release, update the `unreleased` heading to the tag being gen
 
 ## unreleased
 
+* [CHANGE] [#1158](https://github.com/k8ssandra/k8ssandra-operator/issues/1158) Use the MedusaConfiguration API when creating Medusa configuration
 * [CHANGE] [#1050](https://github.com/k8ssandra/k8ssandra-operator/issues/1050) Remove unnecessary requeues in the Medusa controllers
 * [CHANGE] [#1165](https://github.com/k8ssandra/k8ssandra-operator/issues/1165) Upgrade to Medusa v0.17.1
 * [FEATURE] [#1157](https://github.com/k8ssandra/k8ssandra-operator/issues/1157) Add the MedusaConfiguration API

apis/k8ssandra/v1alpha1/k8ssandracluster_webhook.go

@@ -35,6 +35,7 @@ var (
 	ErrNoStorageConfig = fmt.Errorf("storageConfig must be defined at cluster level or dc level")
 	ErrNoResourcesSet  = fmt.Errorf("softPodAntiAffinity requires Resources to be set")
 	ErrClusterName     = fmt.Errorf("cluster name can not be changed")
+	ErrNoStoragePrefix = fmt.Errorf("medusa storage prefix must be set when a medusaConfigurationRef is used")
 )
 
 // log is for logging in this package.
@@ -88,6 +89,16 @@ func (r *K8ssandraCluster) validateK8ssandraCluster() error {
 		}
 	}
 
+	// Verify the Medusa storage prefix is explicitly set
+	// only relevant if Medusa is enabled and the MedusaConfiguration object is referenced
+	if r.Spec.Medusa != nil {
+		if r.Spec.Medusa.MedusaConfigurationRef.Name != "" {
+			if r.Spec.Medusa.StorageProperties.Prefix == "" {
+				return ErrNoStoragePrefix
+			}
+		}
+	}
+
 	if err := r.validateStatefulsetNameSize(); err != nil {
 		return err
 	}

apis/k8ssandra/v1alpha1/k8ssandracluster_webhook_test.go

@@ -42,6 +42,7 @@ import (
 	"sigs.k8s.io/controller-runtime/pkg/envtest"
 	logf "sigs.k8s.io/controller-runtime/pkg/log"
 
+	medusaapi "github.com/k8ssandra/k8ssandra-operator/apis/medusa/v1alpha1"
 	reaperapi "github.com/k8ssandra/k8ssandra-operator/apis/reaper/v1alpha1"
 )
 
@@ -145,6 +146,7 @@ func TestWebhook(t *testing.T) {
 	t.Run("NumTokensValidation", testNumTokens)
 	t.Run("NumTokensValidationInUpdate", testNumTokensInUpdate)
 	t.Run("StsNameTooLong", testStsNameTooLong)
+	t.Run("MedusaPrefixMissing", testMedusaPrefixMissing)
 }
 
 func testContextValidation(t *testing.T) {
@@ -407,3 +409,45 @@ func createMinimalClusterObj(name, namespace string) *K8ssandraCluster {
 		},
 	}
 }
+
+func testMedusaPrefixMissing(t *testing.T) {
+	required := require.New(t)
+	createNamespace(required, "short-namespace")
+
+	clusterWithoutMedusa := createMinimalClusterObj("without-medusa", "short-namespace")
+	err := k8sClient.Create(ctx, clusterWithoutMedusa)
+	required.NoError(err)
+
+	clusterWithMedusa := createMinimalClusterObj("with-medusa", "short-namespace")
+	clusterWithMedusa.Spec.Medusa = &medusaapi.MedusaClusterTemplate{
+		StorageProperties: medusaapi.Storage{
+			Prefix: "",
+		},
+	}
+	err = k8sClient.Create(ctx, clusterWithMedusa)
+	required.NoError(err)
+
+	clusterWithoutPrefix := createMinimalClusterObj("without-prefix", "short-namespace")
+	clusterWithoutPrefix.Spec.Medusa = &medusaapi.MedusaClusterTemplate{
+		MedusaConfigurationRef: corev1.ObjectReference{
+			Name: "medusa-config",
+		},
+		StorageProperties: medusaapi.Storage{
+			Prefix: "",
+		},
+	}
+	err = k8sClient.Create(ctx, clusterWithoutPrefix)
+	required.Error(err)
+
+	clusterWithPrefix := createMinimalClusterObj("with-prefix", "short-namespace")
+	clusterWithPrefix.Spec.Medusa = &medusaapi.MedusaClusterTemplate{
+		MedusaConfigurationRef: corev1.ObjectReference{
+			Name: "medusa-config",
+		},
+		StorageProperties: medusaapi.Storage{
+			Prefix: "some-prefix",
+		},
+	}
+	err = k8sClient.Create(ctx, clusterWithPrefix)
+	required.NoError(err)
+}

apis/medusa/v1alpha1/medusa_types.go

@@ -129,6 +129,12 @@ type PodStorageSettings struct {
 }
 
 type MedusaClusterTemplate struct {
+	// MedusaConfigurationRef points to an existing MedusaConfiguration object.
+	// The purpose is to allow shared default settings across several clusters.
+	// StorageProperties override the settings from MedusaConfiguration object to allow customization.
+	// +optional
+	MedusaConfigurationRef corev1.ObjectReference `json:"medusaConfigurationRef,omitempty"`
+
 	// MedusaContainerImage is the image characteristics to use for Medusa containers. Leave nil
 	// to use a default image.
 	// +optional

config/crd/bases/k8ssandra.io_k8ssandraclusters.yaml

@@ -27021,6 +27021,46 @@ spec:
                         format: int32
                         type: integer
                     type: object
+                  medusaConfigurationRef:
+                    description: MedusaConfigurationRef points to an existing MedusaConfiguration
+                      object. The purpose is to allow shared default settings across
+                      several clusters. StorageProperties override the settings from
+                      MedusaConfiguration object to allow customization.
+                    properties:
+                      apiVersion:
+                        description: API version of the referent.
+                        type: string
+                      fieldPath:
+                        description: 'If referring to a piece of an object instead
+                          of an entire object, this string should contain a valid
+                          JSON/Go field access statement, such as desiredState.manifest.containers[2].
+                          For example, if the object reference is to a container within
+                          a pod, this would take on a value like: "spec.containers{name}"
+                          (where "name" refers to the name of the container that triggered
+                          the event) or if no container name is specified "spec.containers[2]"
+                          (container with index 2 in this pod). This syntax is chosen
+                          only to have some well-defined way of referencing a part
+                          of an object. TODO: this design is not final and this field
+                          is subject to change in the future.'
+                        type: string
+                      kind:
+                        description: 'Kind of the referent. More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#types-kinds'
+                        type: string
+                      name:
+                        description: 'Name of the referent. More info: https://kubernetes.io/docs/concepts/overview/working-with-objects/names/#names'
+                        type: string
+                      namespace:
+                        description: 'Namespace of the referent. More info: https://kubernetes.io/docs/concepts/overview/working-with-objects/namespaces/'
+                        type: string
+                      resourceVersion:
+                        description: 'Specific resourceVersion to which this reference
+                          is made, if any. More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#concurrency-control-and-consistency'
+                        type: string
+                      uid:
+                        description: 'UID of the referent. More info: https://kubernetes.io/docs/concepts/overview/working-with-objects/names/#uids'
+                        type: string
+                    type: object
+                    x-kubernetes-map-type: atomic
                   readinessProbe:
                     description: Define the readiness probe settings to use for the
                       Medusa containers.

controllers/k8ssandra/k8ssandracluster_controller_test.go

@@ -101,6 +101,8 @@ func TestK8ssandraCluster(t *testing.T) {
 	t.Run("CreateMultiDcClusterWithStargate", testEnv.ControllerTest(ctx, createMultiDcClusterWithStargate))
 	t.Run("CreateMultiDcClusterWithReaper", testEnv.ControllerTest(ctx, createMultiDcClusterWithReaper))
 	t.Run("CreateMultiDcClusterWithMedusa", testEnv.ControllerTest(ctx, createMultiDcClusterWithMedusa))
+	t.Run("CreateSingleDcClusterWithMedusaConfigRef", testEnv.ControllerTest(ctx, createSingleDcClusterWithMedusaConfigRef))
+	t.Run("CreatingSingleDcClusterWithoutPrefixInClusterSpecFail", testEnv.ControllerTest(ctx, creatingSingleDcClusterWithoutPrefixInClusterSpecFails))
 	t.Run("CreateSingleDcClusterNoAuth", testEnv.ControllerTest(ctx, createSingleDcClusterNoAuth))
 	t.Run("CreateSingleDcClusterAuth", testEnv.ControllerTest(ctx, createSingleDcClusterAuth))
 	t.Run("CreateSingleDcClusterAuthExternalSecrets", testEnv.ControllerTest(ctx, createSingleDcClusterAuthExternalSecrets))

controllers/k8ssandra/medusa_reconciler.go

@@ -3,6 +3,9 @@ package k8ssandra
 import (
 	"context"
 	"fmt"
+	"github.com/adutra/goalesce"
+	medusaapi "github.com/k8ssandra/k8ssandra-operator/apis/medusa/v1alpha1"
+	"k8s.io/apimachinery/pkg/types"
 
 	"github.com/go-logr/logr"
 	api "github.com/k8ssandra/k8ssandra-operator/apis/k8ssandra/v1alpha1"
@@ -21,17 +24,23 @@ import (
 // Create all things Medusa related in the cassdc podTemplateSpec
 func (r *K8ssandraClusterReconciler) reconcileMedusa(
 	ctx context.Context,
-	kc *api.K8ssandraCluster,
+	desiredKc *api.K8ssandraCluster,
 	dcConfig *cassandra.DatacenterConfig,
 	remoteClient client.Client,
 	logger logr.Logger,
 ) result.ReconcileResult {
+	kc := desiredKc.DeepCopy()
 	namespace := utils.FirstNonEmptyString(dcConfig.Meta.Namespace, kc.Namespace)
 	logger.Info("Medusa reconcile for " + dcConfig.CassDcName() + " on namespace " + namespace)
 	medusaSpec := kc.Spec.Medusa
 	if medusaSpec != nil {
 		logger.Info("Medusa is enabled")
 
+		mergeResult := mergeStorageProperties(ctx, remoteClient, namespace, medusaSpec, logger, kc)
+		if mergeResult.IsError() {
+			return result.Error(mergeResult.GetError())
+		}
+
 		// Check that certificates are provided if client encryption is enabled
 		if cassandra.ClientEncryptionEnabled(dcConfig) {
 			if kc.Spec.UseExternalSecrets() {
@@ -203,3 +212,38 @@ func (r *K8ssandraClusterReconciler) reconcileMedusaConfigMap(
 	logger.Info("Medusa ConfigMap successfully reconciled")
 	return result.Continue()
 }
+
+func mergeStorageProperties(
+	ctx context.Context,
+	remoteClient client.Client,
+	namespace string,
+	medusaSpec *medusaapi.MedusaClusterTemplate,
+	logger logr.Logger,
+	desiredKc *api.K8ssandraCluster,
+) result.ReconcileResult {
+	// check if the StorageProperties are defined in the K8ssandraCluster
+	if medusaSpec.MedusaConfigurationRef.Name == "" {
+		return result.Continue()
+	}
+	storageProperties := &medusaapi.MedusaConfiguration{}
+	configKey := types.NamespacedName{Namespace: namespace, Name: medusaSpec.MedusaConfigurationRef.Name}
+	if err := remoteClient.Get(ctx, configKey, storageProperties); err != nil {
+		logger.Error(err, fmt.Sprintf("failed to get MedusaConfiguration %s", configKey))
+		return result.Error(err)
+	}
+	// check if the StorageProperties from the cluster have the prefix field set
+	// it is required to be present because that's the single thing that differentiates backups of two different clusters
+	if desiredKc.Spec.Medusa.StorageProperties.Prefix == "" {
+		return result.Error(fmt.Errorf("StorageProperties.Prefix is not set in K8ssandraCluster %s", utils.GetKey(desiredKc)))
+	}
+	// try to merge the storage properties. goalesce gives priority to the 2nd argument,
+	// so stuff in the cluster overrides stuff in the config object
+	mergedProperties, err := goalesce.DeepMerge(storageProperties.Spec.StorageProperties, desiredKc.Spec.Medusa.StorageProperties)
+	if err != nil {
+		logger.Error(err, "failed to merge MedusaConfiguration StorageProperties")
+		return result.Error(err)
+	}
+	// copy the merged properties back into the cluster
+	mergedProperties.DeepCopyInto(&desiredKc.Spec.Medusa.StorageProperties)
+	return result.Continue()
+}