encoding some YAML

configmap.yml

---
kind: ConfigMap
data: {}

overlay.yml

#@ load("@ytt:overlay", "overlay")
#@ load("@ytt:data", "data")
#@ load("@ytt:yaml", "yaml")


#@overlay/match by=overlay.subset({"kind":"ConfigMap"})
---
data:
  #@overlay/match missing_ok=True
  config.yaml: #@ yaml.encode(data.values.config_file_contents)
  

values.yml

#@data/values
---
config_file_contents:
  server:
    type: foo
    name: bar
  timeout: 5s