add externalTrafficPolicy toggle

Author: furstblumier

charts/docker-mailserver/templates/service.yaml

@@ -26,11 +26,7 @@ metadata:
 spec:
   ## If a load balancer is being used, ensure that the newer type of LB that passes along IP information is used
   ## rather than the legacy one.
-  {{- if eq .Values.service.type "LoadBalancer" }}
-  externalTrafficPolicy: Local
-  {{- else if eq .Values.service.type "NodePort" }}
-  externalTrafficPolicy: Cluster
-  {{ end }}
+  externalTrafficPolicy: {{ default "Local" .Values.service.externalTrafficPolicy }}
   selector:
     app.kubernetes.io/name: {{ template "dockermailserver.fullname" . }}
     release: "{{ .Release.Name }}"

charts/docker-mailserver/values.yaml

@@ -298,6 +298,11 @@ service:
   ## - LoadBalancer (to the world)
   ## - ClusterIP (to the cluster)
   type: "LoadBalancer"
+  ## Manually overwrite the externalTrafficPolicy. One of:
+  ## - Local
+  ## - Cluster
+  ## Set it to "Local" when used with type "LoadBalancer", unless you have a good reason not to.
+  # externalTrafficPolicy: Local
   ## If there is a port associated with a given service, expose it here.
   # port:
   ## If there is a particular IP that should be used for the service, specify it here.