How to set dynamic values with Kubernetes yaml file

Question

For example, a deployment yaml file:

apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: guestbook
spec:
  replicas: 2
  template:
    metadata         


        

Answer 1

You can also use envsubst when deploying.

e.g.

cat $app/deployment.yaml | envsubst | kubectl apply ...

It will replace all variables in the file with their values. We are successfully using this approach on our CI when deploying to multiple environments, also to inject the CI_TAG etc into the deployments.