[incubator/cassandra] updates to support an alternate k8s scheduler (#14350)

* updates to support an alternate k8s scheduler

Signed-off-by: Sathya Balakrishnan <sathya@portworx.com>

* fix Chart version

Signed-off-by: Sathya Balakrishnan <sathya@portworx.com>

incubator/cassandra/Chart.yaml

@@ -1,6 +1,6 @@
 apiVersion: v1
 name: cassandra
-version: 0.12.2
+version: 0.13.0
 appVersion: 3.11.3
 description: Apache Cassandra is a free and open-source distributed database management
   system designed to handle large amounts of data across many commodity servers, providing

incubator/cassandra/README.md

@@ -31,7 +31,7 @@ helm upgrade "cassandra" incubator/cassandra
 
 This version fixes https://github.com/helm/charts/issues/7803 by removing mutable labels in `spec.VolumeClaimTemplate.metadata.labels` so that it is upgradable.
 
-Until this version, in order to upgrade, you have to delete the Cassandra StatefulSet before upgrading: 
+Until this version, in order to upgrade, you have to delete the Cassandra StatefulSet before upgrading:
 ```bash
 $ kubectl delete statefulset --cascade=false my-cassandra-release
 ```
@@ -121,6 +121,7 @@ The following table lists the configurable parameters of the Cassandra chart and
 | `commandOverrides`                   | Overrides default docker command                | `[]`                                                       |
 | `argsOverrides`                      | Overrides default docker args                   | `[]`                                                       |
 | `env`                                | Custom env variables                            | `{}`                                                       |
+| `schedulerName`                      | Name of k8s scheduler (other than the default)  | `nil`                                                      |
 | `persistence.enabled`                | Use a PVC to persist data                       | `true`                                                     |
 | `persistence.storageClass`           | Storage class of backing PVC                    | `nil` (uses alpha storage class annotation)                |
 | `persistence.accessMode`             | Use volume as ReadOnly or ReadWrite             | `ReadWriteOnce`                                            |

incubator/cassandra/templates/statefulset.yaml

@@ -30,6 +30,9 @@ spec:
 {{ toYaml .Values.podAnnotations | indent 8 }}
 {{- end }}
     spec:
+      {{- if .Values.schedulerName }}
+      schedulerName: "{{ .Values.schedulerName }}"
+      {{- end }}
       hostNetwork: {{ .Values.hostNetwork }}
 {{- if .Values.selector }}
 {{ toYaml .Values.selector | indent 6 }}
@@ -93,7 +96,7 @@ spec:
           value: {{ required "You must fill \".Values.config.seeds\" with list of Cassandra seeds when hostNetwork is set to true" .Values.config.seeds | quote }}
           {{- else }}
           value: "{{- range $i, $e := until $seed_size }}{{ template "cassandra.fullname" $global }}-{{ $i }}.{{ template "cassandra.fullname" $global }}.{{ $global.Release.Namespace }}.svc.{{ $global.Values.config.cluster_domain }}{{- if (lt ( add1 $i ) $seed_size ) }},{{- end }}{{- end }}"
-          {{- end }}     
+          {{- end }}
         - name: MAX_HEAP_SIZE
           value: {{ default "8192M" .Values.config.max_heap_size | quote }}
         - name: HEAP_NEWSIZE

incubator/cassandra/values.yaml

@@ -13,6 +13,11 @@ image:
 service:
   type: ClusterIP
 
+## Use an alternate scheduler, e.g. "stork".
+## ref: https://kubernetes.io/docs/tasks/administer-cluster/configure-multiple-schedulers/
+##
+# schedulerName:
+
 ## Persist data to a persistent volume
 persistence:
   enabled: true