Alert manager configuration could not able to parse when extraVolumes used in Cortex helm chart custom value file

Here is my custom values for the alert manager in Cortex helm chart.

alertmanager:
  enabled: true
  replicas: 1
  resources:
    limits:
      cpu: 50m
      memory: 64Mi
    requests:
      cpu: 10m
      memory: 32Mi
  extraVolumes:
    - name: tmp-dir
      emptyDir: {}
  extraVolumeMounts:
    - name: tmp-dir
      mountPath: /tmp
  sidecar:
    enabled: true
    label: cortex_am
    labelValue: "true"
    folder: /data/configs
    defaultFolderName: /alerts

But I cannot deploy this using

helm install cortex cortex/cortex --namespace cortex -f cortex.yaml --dry-run

Which is throwing following error

Error: INSTALLATION FAILED: YAML parse error on cortex/templates/alertmanager/alertmanager-dep.yaml: error converting YAML to JSON: yaml: line 122: mapping values are not allowed in this context

But when I comment out following segment It is successfully deploy. But I need to create and mount that extra mount in order to get this working.

  extraVolumes:
    - name: tmp-dir
      emptyDir: {}
  extraVolumeMounts:
    - name: tmp-dir
      mountPath: /tmp

further more when using Flux same values inherited form this custom value file is working fine with the helm release and no issue with the indentation as well.

Any one has a clue why this is happening?

Solution

Thank you for reporting this Issue. Should be fixxed after PR https://github.com/cortexproject/cortex-helm-chart/pull/266 is merged.

Disclaimer: maintainer from cortex-helm-chart here.