Allow tenant config file to be managed externally

Add options so that a user can create an externally managed secret
with the tenant config file and point the scheduler to that instead
of the one written by the helm values.

Change-Id: I39cca9dede3fede88a8d38a63196c0c44fae219b

charts/zuul/templates/scheduler/statefulset.yaml

@@ -34,11 +34,20 @@ spec:
           mountPath: /etc/zuul
         - name: {{ include "zuul.fullname" . }}-scheduler
           mountPath: /var/lib/zuul
+{{- if .Values.scheduler.tenantConfigSecret }}
+        - name: zuul-tenant-config
+          mountPath: /etc/zuul/tenant
+{{- end }}
       volumes:
       - name: zuul-config
         secret:
           secretName: {{ include "zuul.fullname" . }}
           defaultMode: 256
+{{- if .Values.scheduler.tenantConfigSecret }}
+      - name: zuul-tenant-config
+        secret:
+          secretName: {{ .Values.scheduler.tenantConfigSecret }}
+{{- end }}
     {{- with .Values.tolerations }}
       tolerations:
 {{ toYaml . | indent 8 }}

charts/zuul/templates/secret.yaml

@@ -21,7 +21,7 @@ stringData:
     root=https://{{ .Values.web.host }}
     port={{ .Values.web.port }}
     [scheduler]
-    tenant_config=/etc/zuul/main.yaml
+    tenant_config={{ .Values.scheduler.tenantConfigPath }}
     [executor]
     private_key_file={{ .Values.executor.private_key_file }}
     {{ range $connection, $options := .Values.connections }}
@@ -34,4 +34,4 @@ stringData:
 {{ toYaml .Values.tenantConfig | indent 4 }}
 {{ if .Values.extraFiles }}
 {{ (toYaml .Values.extraFiles | indent 2) }}
-{{ end }}
+{{ end }}

charts/zuul/values.yaml

@@ -14,6 +14,7 @@ scheduler:
   enabled: true
   gearman:
     port: 4730
+  tenantConfigPath: /etc/zuul/main.yaml
 
 web:
   enabled: true