[stable/postgresql] Update to the recommended pvc patterns. (#461)

* Convert chart postgresql to use the recommended pvc patterns

* document storage class fallback

* bump chart version

stable/postgresql/Chart.yaml

@@ -1,5 +1,5 @@
 name: postgresql
-version: 0.3.0
+version: 0.3.1
 description: Chart for PostgreSQL
 keywords:
 - postgresql

stable/postgresql/README.md

@@ -52,7 +52,7 @@ The following tables lists the configurable parameters of the PostgresSQL chart
 | `postgresPassword`         | Password for the new user.                 | random 10 characters                                       |
 | `postgresDatabase`         | Name for new database to create.           | `postgres`                                                 |
 | `persistence.enabled`      | Use a PVC to persist data                  | `true`                                                     |
-| `persistence.storageClass` | Storage class of backing PVC               | `generic`                                                  |
+| `persistence.storageClass` | Storage class of backing PVC               | `nil` (uses alpha storage class annotation)                |
 | `persistence.accessMode`   | Use volume as ReadOnly or ReadWrite        | `ReadWriteOnce`                                            |
 | `persistence.size`         | Size of data volume                        | `8Gi`                                                      |
 | `resources`                | CPU/Memory resource requests/limits        | Memory: `256Mi`, CPU: `100m`                               |

stable/postgresql/templates/pvc.yaml

@@ -9,7 +9,14 @@ metadata:
     release: "{{ .Release.Name }}"
     heritage: "{{ .Release.Service }}"
   annotations:
-    volume.alpha.kubernetes.io/storage-class: {{ .Values.persistence.storageClass | quote }}
+  {{- if .Values.persistence.storageClass }}
+    volume.beta.kubernetes.io/storage-class: {{ .Values.persistence.storageClass | quote }}
+  {{ else }}
+    volume.alpha.kubernetes.io/storage-class: default
+  {{- end }}
+  {{- range $key, $value := .Values.persistence.annotations }}
+    {{ $key }}: {{ $value }}
+  {{- end }}
 spec:
   accessModes:
     - {{ .Values.persistence.accessMode | quote }}

stable/postgresql/values.yaml

@@ -24,7 +24,10 @@ imageTag: "9.5.4"
 ## Persist data to a persitent volume
 persistence:
   enabled: true
-  storageClass: generic
+  ## If defined, volume.beta.kubernetes.io/storage-class: <storageClass>
+  ## Default: volume.alpha.kubernetes.io/storage-class: default
+  ##
+  # storageClass:
   accessMode: ReadWriteOnce
   size: 8Gi