Merge pull request #114 from elastic/state_of_mind

[elasticsearch] Make persistent volumes optional

Author: Crazybus

elasticsearch/README.md

@@ -80,6 +80,7 @@ helm install --name elasticsearch elastic/elasticsearch --version 7.0.0-alpha1 -
 | `networkHost`              | Value for the [network.host Elasticsearch setting](https://www.elastic.co/guide/en/elasticsearch/reference/current/network.host.html)                                                                                                                                                                                      | `0.0.0.0`                                                                                                                 |
 | `volumeClaimTemplate`      | Configuration for the [volumeClaimTemplate for statefulsets](https://kubernetes.io/docs/concepts/workloads/controllers/statefulset/#stable-storage). You will want to adjust the storage (default `30Gi`) and the `storageClassName` if you are using a different storage class                                            | `accessModes: [ "ReadWriteOnce" ]`<br>`resources.requests.storage: 30Gi`                                                  |
 | `persistence.annotations`  | Additional persistence annotations for the `volumeClaimTemplate`                                                                                                                                                                                                                                                           | `{}`                                                                                                                      |
+| `persistence.enabled`      | Enables a persistent volume for Elasticsearch data. Can be disabled for nodes that only have [roles](https://www.elastic.co/guide/en/elasticsearch/reference/current/modules-node.html) which don't require persistent data.                                                                                               | `true`                                                                                                                    |
 | `antiAffinityTopologyKey`  | The [anti-affinity topology key](https://kubernetes.io/docs/concepts/configuration/assign-pod-node/#affinity-and-anti-affinity). By default this will prevent multiple Elasticsearch nodes from running on the same Kubernetes node                                                                                        | `kubernetes.io/hostname`                                                                                                  |
 | `antiAffinity`             | Setting this to hard enforces the [anti-affinity rules](https://kubernetes.io/docs/concepts/configuration/assign-pod-node/#affinity-and-anti-affinity). If it is set to soft it will be done "best effort". Other values will be ignored.                                                                                  | `hard`                                                                                                                    |
 | `nodeAffinity`             | Value for the [node affinity settings](https://kubernetes.io/docs/concepts/configuration/assign-pod-node/#node-affinity-beta-feature)                                                                                                                                                                                      | `{}`                                                                                                                      |

elasticsearch/templates/statefulset.yaml

@@ -17,6 +17,7 @@ spec:
   podManagementPolicy: {{ .Values.podManagementPolicy }}
   updateStrategy:
     type: {{ .Values.updateStrategy }}
+  {{- if .Values.persistence.enabled }}
   volumeClaimTemplates:
   - metadata:
       name: {{ template "uname" . }}
@@ -26,6 +27,7 @@ spec:
     {{- end }}
     spec:
 {{ toYaml .Values.volumeClaimTemplate | indent 6 }}
+  {{- end }}
   template:
     metadata:
       name: "{{ template "uname" . }}"
@@ -195,8 +197,10 @@ spec:
 {{ toYaml .Values.extraEnvs | indent 10 }}
 {{- end }}
         volumeMounts:
+          {{- if .Values.persistence.enabled }}
           - name: "{{ template "uname" . }}"
             mountPath: /usr/share/elasticsearch/data
+          {{- end }}
           {{- range .Values.secretMounts }}
           - name: {{ .name }}
             mountPath: {{ .path }}

elasticsearch/values.yaml

@@ -76,6 +76,7 @@ volumeClaimTemplate:
       storage: 30Gi
 
 persistence:
+  enabled: true
   annotations: {}
 
 extraVolumes: []