Schema for "users" key is too strict

[Robie Basak]

Against cc_users_groups, I have some configurations that use:

#cloud-config
disable_root: false
users: []

This used to work. I think it's a reasonable configuration: "please make root work, and don't create a non-root user". I'm doing this in order to have management of users/groups done later, not by cloud-init, on these instances.

On booting Ubuntu 22.04 (cloud-init 22.3.4-0ubuntu1~22.04.1), I got:

[ 30.621713] cloud-init[505]: 2022-12-13 03:35:09,073 - schema.py[WARNING]: Invalid cloud-config provided: Please run 'sudo cloud-init schema --system' to see the schema errors.

# cloud-init schema --system
Cloud config schema deprecations:
Error:
Cloud config schema errors: users: [] is too short

This seems to be caused by cloudinit/config/schemas/schema-cloud-config-v1.json specifying "minItems": 1 against the "users" key.

Expected behaviour: the above configuration works as before, with root login permitted but no other users created.

Actual behaviour: unexpected schema warning. However I did get root access as desired, and the ubuntu user does not exist. So perhaps the validation isn't enforced yet?

[James Falcon (falcojr)]

Yes, the use case makes sense. You are correct in that it is only a warning, but it's a warning we should fix.

[Robie Basak (racb)]

Thanks! I appreciate your confirmation that it's just a warning that I can ignore for now :)

I said:

> However I did get root access as desired, and the ubuntu user does exist.

I meant to say that the ubuntu *does not* exist. I'll fix the description.

[Chad Smith (chad.smith)]

Fix committed in upstream here https://github.com/canonical/cloud-init/commit/3ee384680e0a615834c1cb386be88c94f004b9b5

[James Falcon (falcojr)]

Tracked in Github Issues as https://github.com/canonical/cloud-init/issues/4055