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kubernetesnginxkubernetes-helmingress-controller

Is there a way to generate a helm install script from a ConfigMap?

I have a ConfigMap for a nginx ingress controller. Are there any commands I can use that can generate a helm install script for the ConfigMap?

Clarification: I was wondering if there is some way to generate from a ConfigMap a helm install script, an install ingress shell script. There may not be such a thing. Just asking. It would be a nice feature.

Solution

  • It is not possible to directly generate a Helm install script from a ConfigMap. But you can create a Helm chart that uses the ConfigMap. ConfigMaps allow you to decouple configuration artifacts from image content to keep containerized applications portable.

    Create test-chart

    Create templates/configmap.yaml

    apiVersion: v1
kind: ConfigMap
metadata:
 name: my-config
 labels:
   app: {{ template "app.prefix" . }}
data:
 application.conf: |-
{{ .Files.Get "config/application.config" | nindent 4 }}

    and provide your own values.yaml

    The Helm is looking for the "config" under the "templates" folder.

    Try moving the config folder under templates:

       /chart
     /templates
       my-config-map.yaml
       /config
         application.config

    or change (.Files.Glob "config/") to (.Files.Glob "../config/")

    Finally Install chart / use --dry-run Go to main directory ~/test-chart, where you have files like below charts Chart.yaml configmap templates values.yaml

    Now you can helm install chart or use --dry-run option before, to check how configuration YAMLs would look like. You have to display what YAML gets executed by Helm using the: --dry-run --debug options at the end of helm install command. there is controller executed with the: --configmap={namespace-where-the-nginx-ingress-is-deployed}/{name-of-the-helm-chart}-nginx-ingress-controller. In order to load your ConfigMap you need to override it with your own (check out the namespace).