[memcached] Unhardcode port in exporter

* Pick up port for exporter from endpoints
* Drop exporter port from service as we should not use
  service that do loadbalancing among pods which are independent

Change-Id: I0408039ba87aca5b8b3c9333644fa0c92f0ca01a

memcached/templates/bin/_memcached-exporter.sh.tpl

@@ -18,7 +18,7 @@ set -ex
 COMMAND="${@:-start}"
 
 function start () {
-  exec /bin/memcached_exporter
+  exec /bin/memcached_exporter --memcached.address "$MEMCACHED_HOST:$MEMCACHED_PORT"
 }
 
 function stop () {

memcached/templates/service.yaml

@@ -24,10 +24,6 @@ spec:
   ports:
     - name: memcache
       port: {{ tuple "oslo_cache" "internal" "memcache" . | include "helm-toolkit.endpoints.endpoint_port_lookup" }}
-{{- if .Values.monitoring.prometheus.enabled }}
-    - name: metrics
-      port: {{ tuple "oslo_cache" "internal" "metrics" . | include "helm-toolkit.endpoints.endpoint_port_lookup" }}
-{{- end }}
   selector:
 {{ tuple $envAll "memcached" "server" | include "helm-toolkit.snippets.kubernetes_metadata_labels" | indent 4 }}
 {{ .Values.network.memcached | include "helm-toolkit.snippets.service_params" | indent 2 }}

memcached/templates/statefulset.yaml

@@ -102,6 +102,11 @@ spec:
               readOnly: true
 {{- if .Values.monitoring.prometheus.enabled }}
         - name: memcached-exporter
+          env:
+          - name: MEMCACHED_HOST
+            value: 127.0.0.1
+          - name: MEMCACHED_PORT
+            value: {{ tuple "oslo_cache" "internal" "memcache" . | include "helm-toolkit.endpoints.endpoint_port_lookup" | quote }}
 {{ tuple $envAll "prometheus_memcached_exporter" | include "helm-toolkit.snippets.image" | indent 10 }}
 {{ tuple $envAll $envAll.Values.pod.resources.prometheus_memcached_exporter | include "helm-toolkit.snippets.kubernetes_resources" | indent 10 }}
 {{ dict "envAll" $envAll "application" "server" "container" "memcached_exporter" | include "helm-toolkit.snippets.kubernetes_container_security_context" | indent 10 }}