EVEREST-1874 | support volume expansion for PXC

api/v1alpha1/databasecluster_types.go

@@ -49,6 +49,8 @@ const (
 	AppStateRestoring AppState = "restoring"
 	// AppStateDeleting is a deleting state.
 	AppStateDeleting AppState = "deleting"
+	// AppStateResizingVolumes is the state when PVCs are being resized.
+	AppStateResizingVolumes = "resizingVolumes"
 	// AppStateNew represents a newly created cluster that has not yet been reconciled.
 	AppStateNew AppState = ""
 
@@ -355,6 +357,20 @@ type DatabaseClusterSpec struct {
 	Sharding *Sharding `json:"sharding,omitempty"`
 }
 
+const (
+	// ConditionTypeCannotResizeVolume is a condition type that indicates that the volume cannot be resized.
+	ConditionTypeCannotResizeVolume = "CannotResizeVolume"
+)
+
+const (
+	// ReasonStorageClassDoesNotSupportExpansion is a reason for condition ConditionTypeCannotExpandStorage
+	// when the storage class does not support volume expansion.
+	ReasonStorageClassDoesNotSupportExpansion = "StorageClassDoesNotSupportExpansion"
+	// ReasonCannotShrinkVolume is a reason for condition ConditionTypeCannotResizeVolume
+	// when the volume cannot be shrunk.
+	ReasonCannotShrinkVolume = "CannotShrinkVolume"
+)
+
 // DatabaseClusterStatus defines the observed state of DatabaseCluster.
 type DatabaseClusterStatus struct {
 	// ObservedGeneration is the most recent generation observed for this DatabaseCluster.
@@ -381,6 +397,8 @@ type DatabaseClusterStatus struct {
 	RecommendedCRVersion *string `json:"recommendedCRVersion,omitempty"`
 	// Details provides full status of the upstream cluster as a plain text.
 	Details string `json:"details,omitempty"`
+	// Conditions contains the observed conditions of the DatabaseCluster.
+	Conditions []metav1.Condition `json:"conditions,omitempty"`
 }
 
 //+kubebuilder:object:root=true

bundle/manifests/everest-operator.clusterserviceversion.yaml

@@ -78,7 +78,7 @@ metadata:
         }
       ]
     capabilities: Basic Install
-    createdAt: "2025-02-14T15:05:36Z"
+    createdAt: "2025-03-12T11:23:36Z"
     operators.operatorframework.io/builder: operator-sdk-v1.38.0
     operators.operatorframework.io/project_layout: go.kubebuilder.io/v4
   name: everest-operator.v0.0.0

bundle/manifests/everest.percona.com_databaseclusters.yaml

@@ -411,6 +411,63 @@ spec:
               activeStorage:
                 description: ActiveStorage is the storage used in cluster (psmdb only)
                 type: string
+              conditions:
+                description: Conditions contains the observed conditions of the DatabaseCluster.
+                items:
+                  description: Condition contains details for one aspect of the current
+                    state of this API Resource.
+                  properties:
+                    lastTransitionTime:
+                      description: |-
+                        lastTransitionTime is the last time the condition transitioned from one status to another.
+                        This should be when the underlying condition changed.  If that is not known, then using the time when the API field changed is acceptable.
+                      format: date-time
+                      type: string
+                    message:
+                      description: |-
+                        message is a human readable message indicating details about the transition.
+                        This may be an empty string.
+                      maxLength: 32768
+                      type: string
+                    observedGeneration:
+                      description: |-
+                        observedGeneration represents the .metadata.generation that the condition was set based upon.
+                        For instance, if .metadata.generation is currently 12, but the .status.conditions[x].observedGeneration is 9, the condition is out of date
+                        with respect to the current state of the instance.
+                      format: int64
+                      minimum: 0
+                      type: integer
+                    reason:
+                      description: |-
+                        reason contains a programmatic identifier indicating the reason for the condition's last transition.
+                        Producers of specific condition types may define expected values and meanings for this field,
+                        and whether the values are considered a guaranteed API.
+                        The value should be a CamelCase string.
+                        This field may not be empty.
+                      maxLength: 1024
+                      minLength: 1
+                      pattern: ^[A-Za-z]([A-Za-z0-9_,:]*[A-Za-z0-9_])?$
+                      type: string
+                    status:
+                      description: status of the condition, one of True, False, Unknown.
+                      enum:
+                      - "True"
+                      - "False"
+                      - Unknown
+                      type: string
+                    type:
+                      description: type of condition in CamelCase or in foo.example.com/CamelCase.
+                      maxLength: 316
+                      pattern: ^([a-z0-9]([-a-z0-9]*[a-z0-9])?(\.[a-z0-9]([-a-z0-9]*[a-z0-9])?)*/)?(([A-Za-z0-9][-A-Za-z0-9_.]*)?[A-Za-z0-9])$
+                      type: string
+                  required:
+                  - lastTransitionTime
+                  - message
+                  - reason
+                  - status
+                  - type
+                  type: object
+                type: array
               crVersion:
                 description: CRVersion is the observed version of the CR used with
                   the underlying operator.

config/crd/bases/everest.percona.com_databaseclusters.yaml

@@ -411,6 +411,63 @@ spec:
               activeStorage:
                 description: ActiveStorage is the storage used in cluster (psmdb only)
                 type: string
+              conditions:
+                description: Conditions contains the observed conditions of the DatabaseCluster.
+                items:
+                  description: Condition contains details for one aspect of the current
+                    state of this API Resource.
+                  properties:
+                    lastTransitionTime:
+                      description: |-
+                        lastTransitionTime is the last time the condition transitioned from one status to another.
+                        This should be when the underlying condition changed.  If that is not known, then using the time when the API field changed is acceptable.
+                      format: date-time
+                      type: string
+                    message:
+                      description: |-
+                        message is a human readable message indicating details about the transition.
+                        This may be an empty string.
+                      maxLength: 32768
+                      type: string
+                    observedGeneration:
+                      description: |-
+                        observedGeneration represents the .metadata.generation that the condition was set based upon.
+                        For instance, if .metadata.generation is currently 12, but the .status.conditions[x].observedGeneration is 9, the condition is out of date
+                        with respect to the current state of the instance.
+                      format: int64
+                      minimum: 0
+                      type: integer
+                    reason:
+                      description: |-
+                        reason contains a programmatic identifier indicating the reason for the condition's last transition.
+                        Producers of specific condition types may define expected values and meanings for this field,
+                        and whether the values are considered a guaranteed API.
+                        The value should be a CamelCase string.
+                        This field may not be empty.
+                      maxLength: 1024
+                      minLength: 1
+                      pattern: ^[A-Za-z]([A-Za-z0-9_,:]*[A-Za-z0-9_])?$
+                      type: string
+                    status:
+                      description: status of the condition, one of True, False, Unknown.
+                      enum:
+                      - "True"
+                      - "False"
+                      - Unknown
+                      type: string
+                    type:
+                      description: type of condition in CamelCase or in foo.example.com/CamelCase.
+                      maxLength: 316
+                      pattern: ^([a-z0-9]([-a-z0-9]*[a-z0-9])?(\.[a-z0-9]([-a-z0-9]*[a-z0-9])?)*/)?(([A-Za-z0-9][-A-Za-z0-9_.]*)?[A-Za-z0-9])$
+                      type: string
+                  required:
+                  - lastTransitionTime
+                  - message
+                  - reason
+                  - status
+                  - type
+                  type: object
+                type: array
               crVersion:
                 description: CRVersion is the observed version of the CR used with
                   the underlying operator.

deploy/bundle.yaml

@@ -754,6 +754,62 @@ spec:
               activeStorage:
                 description: ActiveStorage is the storage used in cluster (psmdb only)
                 type: string
+              conditions:
+                description: Conditions contains the observed conditions of the DatabaseCluster.
+                items:
+                  description: Condition contains details for one aspect of the current state of this API Resource.
+                  properties:
+                    lastTransitionTime:
+                      description: |-
+                        lastTransitionTime is the last time the condition transitioned from one status to another.
+                        This should be when the underlying condition changed.  If that is not known, then using the time when the API field changed is acceptable.
+                      format: date-time
+                      type: string
+                    message:
+                      description: |-
+                        message is a human readable message indicating details about the transition.
+                        This may be an empty string.
+                      maxLength: 32768
+                      type: string
+                    observedGeneration:
+                      description: |-
+                        observedGeneration represents the .metadata.generation that the condition was set based upon.
+                        For instance, if .metadata.generation is currently 12, but the .status.conditions[x].observedGeneration is 9, the condition is out of date
+                        with respect to the current state of the instance.
+                      format: int64
+                      minimum: 0
+                      type: integer
+                    reason:
+                      description: |-
+                        reason contains a programmatic identifier indicating the reason for the condition's last transition.
+                        Producers of specific condition types may define expected values and meanings for this field,
+                        and whether the values are considered a guaranteed API.
+                        The value should be a CamelCase string.
+                        This field may not be empty.
+                      maxLength: 1024
+                      minLength: 1
+                      pattern: ^[A-Za-z]([A-Za-z0-9_,:]*[A-Za-z0-9_])?$
+                      type: string
+                    status:
+                      description: status of the condition, one of True, False, Unknown.
+                      enum:
+                      - "True"
+                      - "False"
+                      - Unknown
+                      type: string
+                    type:
+                      description: type of condition in CamelCase or in foo.example.com/CamelCase.
+                      maxLength: 316
+                      pattern: ^([a-z0-9]([-a-z0-9]*[a-z0-9])?(\.[a-z0-9]([-a-z0-9]*[a-z0-9])?)*/)?(([A-Za-z0-9][-A-Za-z0-9_.]*)?[A-Za-z0-9])$
+                      type: string
+                  required:
+                  - lastTransitionTime
+                  - message
+                  - reason
+                  - status
+                  - type
+                  type: object
+                type: array
               crVersion:
                 description: CRVersion is the observed version of the CR used with the underlying operator.
                 type: string

internal/controller/common/helper.go

@@ -35,6 +35,7 @@ import (
 	storagev1 "k8s.io/api/storage/v1"
 	k8serrors "k8s.io/apimachinery/pkg/api/errors"
 	"k8s.io/apimachinery/pkg/api/meta"
+	"k8s.io/apimachinery/pkg/api/resource"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
 	"k8s.io/apimachinery/pkg/fields"
@@ -793,3 +794,90 @@ func toUnstructured(obj runtime.Object) (*unstructured.Unstructured, error) {
 	}
 	return ud, nil
 }
+
+const (
+	storageClassDefaultAnnotation = "storageclass.kubernetes.io/is-default-class"
+)
+
+func storageClassSupportsVolumeExpansion(ctx context.Context, c client.Client, className *string) (bool, error) {
+	storageClass, err := getStorageClassOrDefault(ctx, c, className)
+	if err != nil {
+		return false, fmt.Errorf("getStorageClassOrDefault failed: %w", err)
+	}
+	return *storageClass.AllowVolumeExpansion, nil
+}
+
+func getStorageClassOrDefault(ctx context.Context, c client.Client, scName *string) (*storagev1.StorageClass, error) {
+	storageClass := &storagev1.StorageClass{}
+	if scName == nil {
+		storageClasses := &storagev1.StorageClassList{}
+		if err := c.List(ctx, storageClasses); err != nil {
+			return nil, err
+		}
+		for _, sc := range storageClasses.Items {
+			if sc.Annotations[storageClassDefaultAnnotation] == "true" {
+				return &sc, nil
+			}
+		}
+		return nil, errors.New("no default storage class found")
+	}
+	if err := c.Get(ctx, types.NamespacedName{Name: *scName}, storageClass); err != nil {
+		return nil, err
+	}
+	return storageClass, nil
+}
+
+// ConfigureStorage handles storage configuration and volume expansion checks for the given database cluster.
+func ConfigureStorage(
+	ctx context.Context,
+	c client.Client,
+	db *everestv1alpha1.DatabaseCluster,
+	currentSize resource.Quantity,
+	setStorageSizeFunc func(resource.Quantity),
+) error {
+	meta.RemoveStatusCondition(&db.Status.Conditions, everestv1alpha1.ConditionTypeCannotResizeVolume)
+
+	desiredSize := db.Spec.Engine.Storage.Size
+	storageClass := db.Spec.Engine.Storage.Class
+
+	// We cannot shrink the volume size.
+	hasStorageShrunk := currentSize.Cmp(desiredSize) > 0 && !currentSize.IsZero()
+	if hasStorageShrunk {
+		meta.SetStatusCondition(&db.Status.Conditions, metav1.Condition{
+			Type:               everestv1alpha1.ConditionTypeCannotResizeVolume,
+			Status:             metav1.ConditionTrue,
+			Reason:             everestv1alpha1.ReasonCannotShrinkVolume,
+			LastTransitionTime: metav1.Now(),
+			ObservedGeneration: db.GetGeneration(),
+		})
+		setStorageSizeFunc(currentSize)
+		return nil
+	}
+
+	// Check if storage size is being expanded. If not, set the desired size and return early.
+	hasStorageExpanded := currentSize.Cmp(desiredSize) < 0 && !currentSize.IsZero()
+	if !hasStorageExpanded {
+		setStorageSizeFunc(desiredSize)
+		return nil
+	}
+
+	allowedByStorageClass, err := storageClassSupportsVolumeExpansion(ctx, c, storageClass)
+	if err != nil {
+		return fmt.Errorf("failed to check if storage class supports volume expansion: %w", err)
+	}
+
+	if !allowedByStorageClass {
+		meta.SetStatusCondition(&db.Status.Conditions, metav1.Condition{
+			Type:               everestv1alpha1.ConditionTypeCannotResizeVolume,
+			Status:             metav1.ConditionTrue,
+			Reason:             everestv1alpha1.ReasonStorageClassDoesNotSupportExpansion,
+			LastTransitionTime: metav1.Now(),
+			ObservedGeneration: db.GetGeneration(),
+		})
+		setStorageSizeFunc(currentSize)
+		return nil
+	}
+
+	setStorageSizeFunc(desiredSize)
+	return nil
+}