[stable/mariadb] Fix chart not being upgradable

stable/mariadb/Chart.yaml

@@ -1,5 +1,5 @@
 name: mariadb
-version: 4.4.2
+version: 5.0.0
 appVersion: 10.1.36
 description: Fast, reliable, scalable, and easy to use open-source relational database system. MariaDB Server is intended for mission-critical, heavy-load production systems as well as for embedding into mass-deployed software. Highly available MariaDB cluster.
 keywords:

stable/mariadb/README.md

@@ -147,3 +147,14 @@ The allowed extensions are `.sh`, `.sql` and `.sql.gz`.
 The [Bitnami MariaDB](https://github.com/bitnami/bitnami-docker-mariadb) image stores the MariaDB data and configurations at the `/bitnami/mariadb` path of the container.
 
 The chart mounts a [Persistent Volume](kubernetes.io/docs/user-guide/persistent-volumes/) volume at this location. The volume is created using dynamic volume provisioning, by default. An existing PersistentVolumeClaim can be defined.
+
+## Upgrading
+
+### To 5.0.0
+
+Backwards compatibility is not guaranteed unless you modify the labels used on the chart's deployments.
+Use the workaround below to upgrade from versions previous to 5.0.0. The following example assumes that the release name is mariadb:
+
+```console
+$ kubectl delete statefulset opencart-mariadb --cascade=false
+```

stable/mariadb/templates/master-statefulset.yaml

@@ -9,6 +9,11 @@ metadata:
     release: {{ .Release.Name | quote }}
     heritage: {{ .Release.Service | quote }}
 spec:
+  selector:
+    matchLabels:
+      release: "{{ .Release.Name }}"
+      component: "master"
+      app: {{ template "mariadb.name" . }}
   serviceName: "{{ template "master.fullname" . }}"
   replicas: 1
   updateStrategy:
@@ -208,4 +213,4 @@ spec:
 {{- else }}
         - name: "data"
           emptyDir: {}
-{{- end }}
+{{- end }}

stable/mariadb/templates/slave-statefulset.yaml

@@ -10,6 +10,11 @@ metadata:
     release: {{ .Release.Name | quote }}
     heritage: {{ .Release.Service | quote }}
 spec:
+  selector:
+    matchLabels:
+      release: "{{ .Release.Name }}"
+      component: "slave"
+      app: {{ template "mariadb.name" . }}
   serviceName: "{{ template "slave.fullname" . }}"
   replicas: {{ .Values.slave.replicas }}
   updateStrategy: