[stable/postgresql] Add read-only connection to the replica slaves (#10186)

Signed-off-by: Javier J. Salmeron Garcia <jsalmeron@bitnami.com>

stable/postgresql/Chart.yaml

@@ -1,5 +1,5 @@
 name: postgresql
-version: 3.5.0
+version: 3.6.0
 appVersion: 10.6.0
 description: Chart for PostgreSQL, an object-relational database management system (ORDBMS) with an emphasis on extensibility and on standards-compliance.
 keywords:

stable/postgresql/templates/NOTES.txt

@@ -19,8 +19,10 @@
 
 PostgreSQL can be accessed via port 5432 on the following DNS name from within your cluster:
 
-    {{ template "postgresql.fullname" . }}.{{ .Release.Namespace }}.svc.cluster.local
-
+    {{ template "postgresql.fullname" . }}.{{ .Release.Namespace }}.svc.cluster.local - Read/Write connection
+{{- if .Values.replication.enabled }}
+    {{ template "postgresql.fullname" . }}-read.{{ .Release.Namespace }}.svc.cluster.local - Read only connection
+{{- end }}
 To get the password for "{{ .Values.postgresqlUsername }}" run:
 
     export POSTGRESQL_PASSWORD=$(kubectl get secret --namespace {{ .Release.Namespace }} {{ if .Values.existingSecret }}{{ .Values.existingSecret }}{{ else }}{{ template "postgresql.fullname" . }}{{ end }} -o jsonpath="{.data.postgresql-password}" | base64 --decode)

stable/postgresql/templates/svc-read.yaml

@@ -0,0 +1,31 @@
+{{- if .Values.replication.enabled }}
+apiVersion: v1
+kind: Service
+metadata:
+  name: {{ template "postgresql.fullname" . }}-read
+  labels:
+    app: {{ template "postgresql.name" . }}
+    chart: {{ template "postgresql.chart" . }}
+    release: {{ .Release.Name | quote }}
+    heritage: {{ .Release.Service | quote }}
+{{- with .Values.service.annotations }}
+  annotations:
+{{ toYaml . | indent 4 }}
+{{- end }}
+spec:
+  type: {{ .Values.service.type }}
+  {{- if and .Values.service.loadBalancerIP (eq .Values.service.type "LoadBalancer") }}
+  loadBalancerIP: {{ .Values.service.loadBalancerIP }}
+  {{- end }}
+  ports:
+  - name: postgresql
+    port:  {{ .Values.service.port }}
+    targetPort: postgresql
+    {{- if .Values.service.nodePort }}
+    nodePort: {{ .Values.service.nodePort }}
+    {{- end }}
+  selector:
+    app: {{ template "postgresql.name" . }}
+    release: {{ .Release.Name | quote }}
+    role: slave
+{{- end }}