Introduce hard antiAffinity and simplify config using matchLabels instead of matchExpressions (#1629)

stable/memcached/Chart.yaml

@@ -1,5 +1,5 @@
 name: memcached
-version: 1.1.0
+version: 1.2.0
 description: Free & open source, high-performance, distributed memory object caching system.
 keywords:
 - memcached

stable/memcached/templates/statefulset.yaml

@@ -20,16 +20,23 @@ spec:
     spec:
       affinity:
         podAntiAffinity:
+        {{- if eq .Values.AntiAffinity "hard" }}
+          requiredDuringSchedulingIgnoredDuringExecution:
+          - topologyKey: "kubernetes.io/hostname"
+            labelSelector:
+              matchLabels:
+                app:  {{ template "fullname" . }}
+                release: {{ .Release.Name | quote }}
+        {{- else if eq .Values.AntiAffinity "soft" }}
           preferredDuringSchedulingIgnoredDuringExecution:
           - weight: 5
             podAffinityTerm:
+            - topologyKey: "kubernetes.io/hostname"
               labelSelector:
-                matchExpressions:
-                - key: app
-                  operator: In
-                  values:
-                  -  "{{ template "fullname" . }}"  
-              topologyKey: "kubernetes.io/hostname"
+                matchLabels:
+                  app:  {{ template "fullname" . }}
+                  release: {{ .Release.Name | quote }}
+        {{- end }}
       containers:
       - name: {{ template "fullname" . }}
         image: {{ .Values.image }}

stable/memcached/values.yaml

@@ -12,6 +12,9 @@ image: memcached:1.4.36-alpine
 
 ##Replica count 
 replicaCount: 3
+
+## Select AnitAffinity as either hard or soft, default is hard
+AntiAffinity: "hard"
   
 memcached:
   ## Various values that get set as command-line flags.