How to specify arrays and maps in kubernetes service yaml spec?

April 3, 2023

I’m trying to send my kubernetes spec a list. My yaml looks like this:

---
apiVersion: v1
kind: Application
metadata:
  name: my-app
spec:
  env:
    - name: ENV1
      value: http://someurl.com
    - name: ENV2
      value: val2

    - name: AN_ENV_LIST
      value:
        - val2
        - val3

But of course I get an error:

invalid type for v1.Application.spec.env.value: got "array", expected "string"

My question is, is this even possible with kubernetes?

How do I specify a list?

And a bonus question – what about maps? Is that possible?

>Solution :

Environment variables are of type string, so you cannot pass an array in a single variable.

You can either encode the array to be a string, but the application must be aware of that encoding. Alternatively pass multiple environment variables, if the application supports that.