[stable/grafana] Make extraVolumeMounts[].existingClaim optional

stable/grafana/Chart.yaml

@@ -1,6 +1,6 @@
 apiVersion: v1
 name: grafana
-version: 5.5.5
+version: 5.5.6
 appVersion: 7.1.1
 kubeVersion: "^1.8.0-0"
 description: The leading tool for querying and visualizing time series and metrics.

stable/grafana/README.md

@@ -206,6 +206,23 @@ ingress:
     readOnly: false
 ```
 
+### Example of extraVolumeMounts with extraContainerVolumes
+
+If you want to trust system's certificates in Grafana, so that you can add SSL URIs to your datasources for example,
+you can use a construction like this:
+
+```yaml
+extraVolumeMounts:
+- name: etc-ssl-certs
+  mountPath: /etc/ssl/certs
+
+extraContainerVolumes:
+- name: etc-ssl-certs
+  hostPath:
+    path: /etc/ssl/certs
+    type: Directory
+```
+
 ## Import dashboards
 
 There are a few methods to import dashboards to Grafana. Below are some examples and explanations as to how to use each method:

stable/grafana/templates/_pod.tpl

@@ -434,9 +434,11 @@ volumes:
       defaultMode: {{ .defaultMode }}
 {{- end }}
 {{- range .Values.extraVolumeMounts }}
+  {{- if .existingClaim }}
   - name: {{ .name }}
     persistentVolumeClaim:
       claimName: {{ .existingClaim }}
+  {{- end }}
 {{- end }}
 {{- range .Values.extraEmptyDirMounts }}
   - name: {{ .name }}