Support additional volumes inside the containers

[gwvandesteeg]

Add ability to specify additional volumes inside the containers so that
they can be utilised and mounted at various locations inside the pod as
needed.

This will need testing and verification.

[JnMik]

Hello guys @gwvandesteeg @moxious

How do you exactly use this ?

I am trying to use this in the values.yml

  ## specify additional volumes to mount in the core container, this can be used
  ## to specify additional storage of material or to inject files from ConfigMaps
  ## into the running container
  additionalVolumes:
  - name: restore-service-key
    secret:
      secretName: neo4j-cronjob-backup
      defaultMode: 0555
  - name: restore-script
    configMap:
      name: "neo4j-cronjob-script"
      defaultMode: 0777
  - name: "neo4j-tls"
    secret:
      secretName: "neo4j-tls"

  ## specify where the additional volumes are mounted in the core container
  additionalVolumeMounts:
  - name: "neo4j-tls"
    mountPath: "/certs/bolt/public.crt"
    subPath: "tls.crt"
    readOnly: true
  - name: "neo4j-tls"
    mountPath: "/certs/bolt/private.key"
    subPath: "tls.key"
    readOnly: true

But keep getting these errors.
coalesce.go:196: warning: cannot overwrite table with non table for additionalVolumeMounts (map[])
coalesce.go:196: warning: cannot overwrite table with non table for additionalVolumes (map[])

Should the properties be written with [] instead of {} ? Like this

  ## specify additional volumes to mount in the core container, this can be used
  ## to specify additional storage of material or to inject files from ConfigMaps
  ## into the running container
  additionalVolumes: []

  ## specify where the additional volumes are mounted in the core container
  additionalVolumeMounts: []

Edited: Seems changing the curly for square brackets in the values.yml fix my issues actually, but I don't know if you have another way to use it that makes more sens.

[moxious]

It's possible that the helm template expansion is mucking something up. Can you please use helm template instead of helm install and paste the part of your expanded YAML that is getting applied? This would let us see what's wrong with your volumes and volume mounts that's going wrong

[JnMik]

Just so you know, helm template is triggering the warning too

coalesce.go:196: warning: cannot overwrite table with non table for additionalVolumeMounts (map[])
coalesce.go:196: warning: cannot overwrite table with non table for additionalVolumes (map[])

Some extract from the helm template command :

# Source: neo4j/templates/core-statefulset.yaml
apiVersion: "apps/v1"
kind: StatefulSet
metadata:
  name: "neo4j-v1-neo4j-core"
[...]
        - name: init-script
          mountPath: /helm-init
        - name: datadir
          mountPath: "/data"
        - name: plugins
          mountPath: /plugins
        - mountPath: /certs/bolt/public.crt
          name: neo4j-tls
          readOnly: true
          subPath: tls.crt
        - mountPath: /certs/bolt/private.key
          name: neo4j-tls
          readOnly: true
          subPath: tls.key
[...]
      volumes:
        - name: init-script
          configMap: 
            name: "neo4j-v1-init-script"
        - name: plugins
          emptyDir: {}
        - name: restore-service-key
          secret:
            defaultMode: 365
            secretName: neo4j-cronjob-backup
        - configMap:
            defaultMode: 511
            name: neo4j-cronjob-script
          name: restore-script
        - name: neo4j-tls
          secret:
            secretName: neo4j-tls
  [...]

It seems like the values are there ? Is that what you expected ?

[JnMik]

I run this just before my helm install / upgrade and it'S working

sed -i 's/additionalVolumes: {}/additionalVolumes: []/g' $MYDIR/neo4j-helm/values.yaml
sed -i 's/additionalVolumeMounts: {}/additionalVolumeMounts: []/g' $MYDIR/neo4j-helm/values.yaml

[moxious]

@JnMik ok - that's helpful. Please open an issue and I'll catch this in a PR sometime next week.

[JnMik]

Thanks mate !