Add support for priorityClassName (fixes #1034)

CHANGELOG/CHANGELOG-1.21.md

@@ -18,3 +18,4 @@ When cutting a new release, update the `unreleased` heading to the tag being gen
 * [CHANGE] [#1441](https://github.com/k8ssandra/k8ssandra-operator/issues/1441) Use k8ssandra-client instead of k8ssandra-tools for CRD upgrades
 * [BUGFIX] [#1383](https://github.com/k8ssandra/k8ssandra-operator/issues/1383) Do not create MedusaBackup if MedusaBakupJob did not fully succeed
 * [ENHANCEMENT] [#1667](https://github.com/k8ssahttps://github.com/k8ssandra/k8ssandra/issues/1667) Add `skipSchemaMigration` option to `K8ssandraCluster.spec.reaper`
+* [FEATURE] [#1034](https://github.com/k8ssandra/k8ssandra-operator/issues/1034) Add support for priorityClassName

apis/k8ssandra/v1alpha1/k8ssandracluster_types.go

@@ -425,6 +425,10 @@ type DatacenterOptions struct {
 	// +optional
 	PodSecurityContext *corev1.PodSecurityContext `json:"podSecurityContext,omitempty"`
 
+	// PodPriorityClassName defines the priority class name for the Cassandra pods.
+	// +optional
+	PodPriorityClassName string `json:"podPriorityClassName,omitempty"`
+
 	// ManagementApiAuth defines the authentication settings for the management API in the Cassandra pods.
 	// +optional
 	ManagementApiAuth *cassdcapi.ManagementApiAuthConfig `json:"managementApiAuth,omitempty"`

charts/k8ssandra-operator/crds/k8ssandra-operator-crds.yaml

@@ -9556,6 +9556,10 @@ spec:
                               type: string
                           type: object
                           x-kubernetes-map-type: atomic
+                        podPriorityClassName:
+                          description: PodPriorityClassName defines the priority class
+                            name for the Cassandra pods.
+                          type: string
                         podSecurityContext:
                           description: PodSecurityContext defines the security context
                             for the Cassandra pods.
@@ -22018,6 +22022,10 @@ spec:
                       configuration. This is only useful when PerNodeConfigMapRef is set.
                       The default is "mikefarah/yq:4".
                     type: string
+                  podPriorityClassName:
+                    description: PodPriorityClassName defines the priority class name
+                      for the Cassandra pods.
+                    type: string
                   podSecurityContext:
                     description: PodSecurityContext defines the security context for
                       the Cassandra pods.

config/crd/bases/k8ssandra.io_k8ssandraclusters.yaml

@@ -9494,6 +9494,10 @@ spec:
                               type: string
                           type: object
                           x-kubernetes-map-type: atomic
+                        podPriorityClassName:
+                          description: PodPriorityClassName defines the priority class
+                            name for the Cassandra pods.
+                          type: string
                         podSecurityContext:
                           description: PodSecurityContext defines the security context
                             for the Cassandra pods.
@@ -21956,6 +21960,10 @@ spec:
                       configuration. This is only useful when PerNodeConfigMapRef is set.
                       The default is "mikefarah/yq:4".
                     type: string
+                  podPriorityClassName:
+                    description: PodPriorityClassName defines the priority class name
+                      for the Cassandra pods.
+                    type: string
                   podSecurityContext:
                     description: PodSecurityContext defines the security context for
                       the Cassandra pods.

pkg/cassandra/datacenter.go

@@ -374,6 +374,7 @@ func Coalesce(clusterName string, clusterTemplate *api.CassandraClusterTemplate,
 	dcConfig.DseWorkloads = mergedOptions.DseWorkloads
 	dcConfig.ManagementApiAuth = mergedOptions.ManagementApiAuth
 	dcConfig.PodTemplateSpec.Spec.SecurityContext = mergedOptions.PodSecurityContext
+	dcConfig.PodTemplateSpec.Spec.PriorityClassName = mergedOptions.PodPriorityClassName
 	dcConfig.PerNodeInitContainerImage = mergedOptions.PerNodeConfigInitContainerImage
 	dcConfig.ServiceAccount = mergedOptions.ServiceAccount
 	dcConfig.ReadOnlyRootFilesystem = mergedOptions.ReadOnlyRootFilesystem

pkg/cassandra/datacenter_test.go

@@ -1281,6 +1281,46 @@ func TestCoalesce(t *testing.T) {
 				},
 			},
 		},
+		{
+			name: "Set priority class name at cluster level",
+			clusterTemplate: &api.CassandraClusterTemplate{
+				DatacenterOptions: api.DatacenterOptions{
+					PodPriorityClassName: "mock-priority",
+				},
+			},
+			dcTemplate: &api.CassandraDatacenterTemplate{},
+			want: &DatacenterConfig{
+				McacEnabled: true,
+				PodTemplateSpec: corev1.PodTemplateSpec{
+					Spec: corev1.PodSpec{
+						Containers:        []corev1.Container{{Name: "cassandra"}},
+						PriorityClassName: "mock-priority",
+					},
+				},
+			},
+		},
+		{
+			name: "Override priority class name",
+			clusterTemplate: &api.CassandraClusterTemplate{
+				DatacenterOptions: api.DatacenterOptions{
+					PodPriorityClassName: "ignored-priority",
+				},
+			},
+			dcTemplate: &api.CassandraDatacenterTemplate{
+				DatacenterOptions: api.DatacenterOptions{
+					PodPriorityClassName: "mock-priority",
+				},
+			},
+			want: &DatacenterConfig{
+				McacEnabled: true,
+				PodTemplateSpec: corev1.PodTemplateSpec{
+					Spec: corev1.PodSpec{
+						Containers:        []corev1.Container{{Name: "cassandra"}},
+						PriorityClassName: "mock-priority",
+					},
+				},
+			},
+		},
 	}
 
 	for _, tc := range tests {
@@ -1376,6 +1416,17 @@ func TestNewDatacenter_ServiceAccount(t *testing.T) {
 	assert.Equal(t, template.ServiceAccount, dc.Spec.ServiceAccountName)
 }
 
+func TestNewDatacenter_PodPriorityClassName(t *testing.T) {
+	template := GetDatacenterConfig()
+	template.PodTemplateSpec.Spec.PriorityClassName = "mock-priority"
+	dc, err := NewDatacenter(
+		types.NamespacedName{Name: "testdc", Namespace: "test-namespace"},
+		&template,
+	)
+	assert.NoError(t, err)
+	assert.Equal(t, "mock-priority", dc.Spec.PodTemplateSpec.Spec.PriorityClassName)
+}
+
 // TestValidateCoalesced_Fail_NoStorageConfig tests that NewDatacenter fails when no storage config is provided.
 func TestValidateDatacenterConfig_Fail_NoStorageConfig(t *testing.T) {
 	template := GetDatacenterConfig()