Fail to apply a config that contains a zero-value datasource

[Kiefer Chang]

The code snippet generates an almost-empty config /tmp/sample.yaml:

name: test
stages:
  default:
  - commands:
    - echo hello
    files: []
    directories: []
    if: ""
    ensure_entities: []
    delete_entities: []
    dns:
      nameservers: []
      search: []
      options: []
      path: ""
    hostname: ""
    name: ""
    sysctl: {}
    authorized_keys: {}
    node: ""
    users: {}
    modules: []
    systemctl:
      enable: []
      disable: []
      start: []
      mask: []
    environment: {}
    environment_file: ""
    datasource:
      providers: []
      path: ""
    layout:
      device: null
    systemd_firstboot: {}
    timesyncd: {}

If I apply the config with yip, it will fail with the following output:

INFO[0000] yip version 0.9.4-gb3de05be3bcf822ebe9c2cc052d4e75892b70187 2021-07-13 05:36:40 UTC
INFO[0000] Executing /tmp/test.yaml
INFO[0000] Executing yip file                            name=test stage=default stages=1
INFO[0000] Processing stage step ''                      commands=1 delete_entities=0 entities=0 files=0 nameserver=0 step=
INFO[0000] Command output: hello
ERRO[0000] No metadata/userdata found. Bye
INFO[0000] Finished yip file execution                   stage=default stages=1 success=false
ERRO[0000] fatal error: 1 error occurred:
	* No metadata/userdata found. Bye

I' not sure if it's because the check here doesn't work. The applying works If I change the datasource to:

    datasource:
      providers: null
      path: ""

I want to programmingly generate a YIP configuration file to be used in cOS. It would be great that zero-value configs can be applied.

[David Cassany Viladomat]

Good catch! Thanks for the detailed report. I am on it to fix it.