Backports: add keyring support

[kenyon]

This adds support for the keyring parameter of apt::source (

puppetlabs-apt/manifests/source.pp

Line 90 in 0871cad

Optional[Stdlib::AbsolutePath] $keyring = undef,

) to the apt::backports class. This is needed to allow for adding signed-by=… to the backports sources.list.d entry created by this class. The default is to use the Debian or Ubuntu archive keyring installed by the debian-archive-keyring or ubuntu-keyring packages. If $key is specified, then that parameter takes precedence to avoid breaking existing setups that specify $key, since otherwise we would be providing both $key and $keyring to apt::source, which is an error (

puppetlabs-apt/manifests/source.pp

Line 136 in 0871cad

fail('parameters key and keyring are mutually exclusive')

).

I didn't make an effort to support linuxmint or other OSes besides Debian and Ubuntu, since we only declare support for Debian and Ubuntu:

puppetlabs-apt/metadata.json

Lines 16 to 32 in 0871cad

	"operatingsystem_support": [
	{
	"operatingsystem": "Debian",
	"operatingsystemrelease": [
	"10",
	"11"
	]
	},
	{
	"operatingsystem": "Ubuntu",
	"operatingsystemrelease": [
	"18.04",
	"20.04",
	"22.04"
	]
	}
	],

But, the best way to support other OSes would be to eliminate params.pp and use hiera data, since the default value for $keyring would be different (linuxmint would use /usr/share/keyrings/linuxmint-keyring.gpg, for example).

Easiest to review the individual commits.

[smortex]

LGTM

[smortex]

But, the best way to support other OSes would be to eliminate params.pp and use hiera data, since the default value for $keyring would be different (linuxmint would use /usr/share/keyrings/linuxmint-keyring.gpg, for example).

That would be great indeed!