I'm using the Helm chart to deploy Spark to Kubernetes in GCE. I want to provide a custom spark-defaults.conf file in a ConfigMap to be deployed to spark-master path /opt/bitnami/spark/conf.

But I don't understand how can I make another file custom-keys.yaml to be deployed to the same path that is referenced from the spark-defaults.conf? The documentation only describes how to override default spark configuration. What is the correct way to load extra files and jars in this case?

I've specified a ConfigMap for spark-master in the values.yaml:

master:
  ## Set a custom configuration by using an existing configMap with the configuration file.
  ##
   configurationConfigMap: master-config

master-config.yaml

kind: ConfigMap
metadata:
  name: master-config
data:
  {{ (.Files.Glob "files/spark-defaults.conf").AsConfig | indent 2 }}