ansible-lint should allow role names beginning with a underscore

[gardar]

Summary

Recently we added a ansible role for common shared tasks to the prometheus ansible collection. The role is named _common (fqcn prometheus.prometheus._common) to distinguish it from the other roles in the collection, as it is a internal role that's only supposed to be used by the other roles and not directly by a user.

ansible-lint generates false positives for that particular role, the role-name rule and the var-naming[no-role-prefix] rule.
The error message for the var-naming[no-role-prefix] rule suggests that the variable should be named exactly like it is already named, for example:

var-naming[no-role-prefix]: Variables names from within roles should use _common_ as a prefix. (vars: _common_service_name)
var-naming[no-role-prefix]: Variables names from within roles should use _common_ as a prefix. (vars: __common_binary_basename)
Error: Variables names from within roles should use _common_ as a prefix. (vars: _common_local_cache_path)
Error: Variables names from within roles should use _common_ as a prefix. (vars: _common_binaries)
Error: Variables names from within roles should use _common_ as a prefix. (vars: _common_binary_name)
Error: Variables names from within roles should use _common_ as a prefix. (vars: _common_binary_install_dir)
Error: Variables names from within roles should use _common_ as a prefix. (vars: _common_config_dir)
Error: Variables names from within roles should use _common_ as a prefix. (vars: _common_binary_url)
Error: Variables names from within roles should use _common_ as a prefix. (vars: _common_checksums_url)

I know the Ansible docs suggest that role names should not begin with a underscore, but Ansible does not seem to have any issues with consuming a role with a name like this, and neither does ansible galaxy have any issues with importing the role. I've tested with every ansible version between 2.9 - 2.17.

Issue Type

• Bug Report

OS / ENVIRONMENT

Run ansible/ansible-lint@main
  with:
    setup_python: true
    expected_return_code: 0
  env:
    ANSIBLE_FORCE_COLOR: true
    ANSIBLE_GALAXY_SERVER_GALAXY_URL: https://galaxy.ansible.com/
    ANSIBLE_GALAXY_SERVER_GALAXY_TIMEOUT: 120
    ANSIBLE_GALAXY_SERVER_LIST: galaxy

Using ansible-lint github action.

STEPS TO REPRODUCE

Desired Behavior

ansible-lint should allow ansible role names beginning with _. At least when they are a part of a collection, continue to disallow a _ prefix in standalone roles is probably a good idea.

Actual Behavior

role-name: Role name _common does not match ``^[a-z][a-z0-9_]*$`` pattern.
roles/_common:1
Error: Role name _common does not match ``^\[a-z]\[a-z0-9_]*$`` pattern.
var-naming[no-role-prefix]: Variables names from within roles should use _common_ as a prefix. (vars: _common_service_name)
var-naming[no-role-prefix]: Variables names from within roles should use _common_ as a prefix. (vars: __common_binary_basename)
Error: Variables names from within roles should use _common_ as a prefix. (vars: _common_local_cache_path)
Error: Variables names from within roles should use _common_ as a prefix. (vars: _common_binaries)
Error: Variables names from within roles should use _common_ as a prefix. (vars: _common_binary_name)
Error: Variables names from within roles should use _common_ as a prefix. (vars: _common_binary_install_dir)
Error: Variables names from within roles should use _common_ as a prefix. (vars: _common_config_dir)
Error: Variables names from within roles should use _common_ as a prefix. (vars: _common_binary_url)
Error: Variables names from within roles should use _common_ as a prefix. (vars: _common_checksums_url)

Please give some details of what is happening. Include a minimum complete
verifiable example with:

• minimized playbook to reproduce the error
• the output of running ansible-lint including the command line used
• if you're getting a stack trace, also the output of
  ansible-playbook --syntax-check playbook

[cavcrosby]

I wonder if this implies that there is a bug elsewhere (e.g. docs, Galaxy), as according to the documentation, the verbiage suggests roles within a collection starting with an underscore shouldn't be able to be imported via Galaxy.

The collection import into Galaxy will fail if a role name does not comply with these rules.

[gardar]

Definitely looks like incorrect information in the docs. Perhaps galaxy struggled with this in the past or maybe it's an issue with standalone roles. Or maybe someone just thought it would be ugly to name roles like that 😃.
In any case, I haven't seen any scenario where that name causes the role to fail.

I've opened up another issue over at ansible/ansible-documentation#2035 and a forum discussion as well. Hopefully someone can shed some light on this.

[alisonlhart]

We're currently following the Ansible documentation for this, but if the circumstances change and documentation is updated, we can reopen this and update the linter accordingly. For now, closing this as not planned.