How to use templates inside templates in helm chart?

Question

I want to use template inside template with "." operator in my helm chart.

Suppose this is my values.yaml

component: my-component
my-component-arguments:
  heap_opts: "heap-opts" 

Now I want to get "heap_opts", but component name is dynamic. How can I do something like this using template?

{{ .Values."{{.Values.component}}-arguments".heap_opts }}

Answer 1

You can do this using get spring function combined with index and printf from text/template package

{{ get (index .Values (printf "%s-arguments" .Values.component)) "heap_opts" }}