add postgres config for ephemeral volumes

charts/postgres-operator/crds/postgresqls.yaml

@@ -577,6 +577,9 @@ spec:
                         - PreferNoSchedule
                     tolerationSeconds:
                       type: integer
+              useEphemeralVolume:
+                type: boolean
+                default: false
               useLoadBalancer:
                 type: boolean
                 description: deprecated

manifests/postgresql.crd.yaml

@@ -575,6 +575,9 @@ spec:
                         - PreferNoSchedule
                     tolerationSeconds:
                       type: integer
+              useEphemeralVolume:
+                type: boolean
+                default: false
               useLoadBalancer:
                 type: boolean
                 description: deprecated

pkg/apis/acid.zalan.do/v1/crds.go

@@ -898,6 +898,9 @@ var PostgresCRDResourceValidation = apiextv1.CustomResourceValidation{
 							},
 						},
 					},
+					"useEphemeralVolume": {
+						Type: "boolean",
+					},
 					"useLoadBalancer": {
 						Type:        "boolean",
 						Description: "deprecated",

pkg/apis/acid.zalan.do/v1/postgresql_type.go

@@ -93,6 +93,9 @@ type PostgresSpec struct {
 	// deprecated json tags
 	InitContainersOld       []v1.Container `json:"init_containers,omitempty"`
 	PodPriorityClassNameOld string         `json:"pod_priority_class_name,omitempty"`
+
+	// Ephemeral settings
+	UseEphemeralVolume *bool `json:"useEphemeralVolume,omitempty"`
 }
 
 // +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object

pkg/apis/acid.zalan.do/v1/zz_generated.deepcopy.go

@@ -881,6 +881,11 @@ func (in *PostgresSpec) DeepCopyInto(out *PostgresSpec) {
 			(*in)[i].DeepCopyInto(&(*out)[i])
 		}
 	}
+	if in.UseEphemeralVolume != nil {
+		in, out := &in.UseEphemeralVolume, &out.UseEphemeralVolume
+		*out = new(bool)
+		**out = **in
+	}
 	return
 }
 

pkg/cluster/k8sres.go

@@ -692,7 +692,6 @@ func generateContainer(
 	privilegedMode bool,
 	privilegeEscalationMode *bool,
 	additionalPodCapabilities *v1.Capabilities,
-	useEphemeralVolumes *bool,
 ) *v1.Container {
 	return &v1.Container{
 		Name:            name,
@@ -1290,10 +1289,12 @@ func (c *Cluster) generateStatefulSet(spec *acidv1.PostgresSpec) (*appsv1.Statef
 		initContainers      []v1.Container
 		sidecarContainers   []v1.Container
 		podTemplate         *v1.PodTemplateSpec
-		volumeClaimTemplate *v1.PersistentVolumeClaim
+		volumeClaimTemplate *[]v1.PersistentVolumeClaim
 		additionalVolumes   = spec.AdditionalVolumes
 	)
 
+	useEphemeralVolume := c.OpConfig.AllowEphemeralVolumes != nil && spec.UseEphemeralVolume != nil && (*c.OpConfig.AllowEphemeralVolumes && *spec.UseEphemeralVolume)
+
 	defaultResources := makeDefaultResources(&c.OpConfig)
 	resourceRequirements, err := c.generateResourceRequirements(
 		spec.Resources, defaultResources, constants.PostgresContainerName)
@@ -1395,7 +1396,6 @@ func (c *Cluster) generateStatefulSet(spec *acidv1.PostgresSpec) (*appsv1.Statef
 		c.OpConfig.Resources.SpiloPrivileged,
 		c.OpConfig.Resources.SpiloAllowPrivilegeEscalation,
 		generateCapabilities(c.OpConfig.AdditionalPodCapabilities),
-		nil,
 	)
 
 	// Patroni responds 200 to probe only if it either owns the leader lock or postgres is running and DCS is accessible
@@ -1495,9 +1495,23 @@ func (c *Cluster) generateStatefulSet(spec *acidv1.PostgresSpec) (*appsv1.Statef
 		return nil, fmt.Errorf("could not generate pod template: %v", err)
 	}
 
-	if volumeClaimTemplate, err = c.generatePersistentVolumeClaimTemplate(spec.Volume.Size,
-		spec.Volume.StorageClass, spec.Volume.Selector); err != nil {
-		return nil, fmt.Errorf("could not generate volume claim template: %v", err)
+	// Generate the volumes, optionally using an ephemeral volume
+	if useEphemeralVolume {
+		empty := make([]v1.PersistentVolumeClaim, 0)
+		volumeClaimTemplate = &empty
+
+		// Also add the ephemeral volume to the spec
+		podTemplate.Spec.Volumes = append(podTemplate.Spec.Volumes, v1.Volume{
+			Name: constants.DataVolumeName,
+			VolumeSource: v1.VolumeSource{
+				EmptyDir: &v1.EmptyDirVolumeSource{},
+			},
+		})
+	} else {
+		if volumeClaimTemplate, err = c.generatePersistentVolumeClaimTemplate(spec.Volume.Size,
+			spec.Volume.StorageClass, spec.Volume.Selector); err != nil {
+			return nil, fmt.Errorf("could not generate volume claim template: %v", err)
+		}
 	}
 
 	// global minInstances and maxInstances settings can overwrite manifest
@@ -1542,7 +1556,7 @@ func (c *Cluster) generateStatefulSet(spec *acidv1.PostgresSpec) (*appsv1.Statef
 			Selector:                             c.labelsSelector(),
 			ServiceName:                          c.serviceName(Master),
 			Template:                             *podTemplate,
-			VolumeClaimTemplates:                 []v1.PersistentVolumeClaim{*volumeClaimTemplate},
+			VolumeClaimTemplates:                 *volumeClaimTemplate,
 			UpdateStrategy:                       updateStrategy,
 			PodManagementPolicy:                  podManagementPolicy,
 			PersistentVolumeClaimRetentionPolicy: &persistentVolumeClaimRetentionPolicy,
@@ -1850,7 +1864,7 @@ func (c *Cluster) addAdditionalVolumes(podSpec *v1.PodSpec,
 }
 
 func (c *Cluster) generatePersistentVolumeClaimTemplate(volumeSize, volumeStorageClass string,
-	volumeSelector *metav1.LabelSelector) (*v1.PersistentVolumeClaim, error) {
+	volumeSelector *metav1.LabelSelector) (*[]v1.PersistentVolumeClaim, error) {
 
 	var storageClassName *string
 	if volumeStorageClass != "" {
@@ -1863,7 +1877,7 @@ func (c *Cluster) generatePersistentVolumeClaimTemplate(volumeSize, volumeStorag
 	}
 
 	volumeMode := v1.PersistentVolumeFilesystem
-	volumeClaim := &v1.PersistentVolumeClaim{
+	volumeClaim := v1.PersistentVolumeClaim{
 		ObjectMeta: metav1.ObjectMeta{
 			Name:        constants.DataVolumeName,
 			Annotations: c.annotationsSet(nil),
@@ -1882,7 +1896,7 @@ func (c *Cluster) generatePersistentVolumeClaimTemplate(volumeSize, volumeStorag
 		},
 	}
 
-	return volumeClaim, nil
+	return &[]v1.PersistentVolumeClaim{volumeClaim}, nil
 }
 
 func (c *Cluster) generateUserSecrets() map[string]*v1.Secret {
@@ -2290,7 +2304,6 @@ func (c *Cluster) generateLogicalBackupJob() (*batchv1.CronJob, error) {
 		c.OpConfig.SpiloPrivileged, // use same value as for normal DB pods
 		c.OpConfig.SpiloAllowPrivilegeEscalation,
 		nil,
-		nil,
 	)
 
 	logicalBackupJobLabel := map[string]string{