Customising Chart Parameters

Customising Chart Parameters

• This is done whilst installing a chart .

• When you install a chart, you also use its default values.

• The Wordpress chart deploys values.yaml and deployment.yaml

• In deployment.yaml, there is a line called value: {{.Values.wordpressBlogName | quote}} - this is where the value is displayed/

  • Then under the values.yaml file, this has wordpressBlogName: User's Blog!. Changing that will change the layout of the Wordpress website.

• The helm install my-release bitnami/wordpress command pulls the chart and deploys the application immediately - we cannot change any of it during this time.

  • To pass in values, can use the --set option. You can pass in any field from the values.yaml file, like so:

      helm install --set wordpressBlogName="Helm Tutorials" my-release bitnami/wordpress
    

  • This can be used multiple times to pass commands into the helm install command.

  • --set wordpressEmail="john@example.com"

• If there are too many values, another option is to move the above --set commands to a custom values file.

• You would create a custom-values.yaml file with these parameters:

  wordpressBlogName: Helm Tutorials
  wordpressEmail: john@example.com
  

• Then to use the above file, you run:

  helm install --values custom-values.yaml my-release bitnami/wordpres
  

• What if we want to override the values.yaml file itself.

  • Use the helm pull command like so:

  • helm pull bitnami/wordpress

  • This pulls the chart in an archived form.

    • Then need to unarchive or uncompress it.

  • helm can also decompress it using helm pull --untar bitnamin/wordpress

    • This creates a directory called wordpress and you can see all of the parts in the chart.

    • Can then edit the values.yaml that way.

  • Then when we want to install the application, we run helm install my-release ./wordpress at the local directory.