NetworkManager allow disabling default plugins

[jalil-salame]

Describe the bug

NetworkManager has a set of default plugins that are enabled:

nixpkgs/nixos/modules/services/networking/networkmanager.nix

Lines 637 to 645 in 314e12b

	networkmanager.plugins = with pkgs; [
	networkmanager-fortisslvpn
	networkmanager-iodine
	networkmanager-l2tp
	networkmanager-openconnect
	networkmanager-openvpn
	networkmanager-vpnc
	networkmanager-sstp
	];

These cannot be disabled through the configuration of the module (e.g. to reduce the NixOS image size).

Steps To Reproduce

N/A

Expected behavior

The module should instead add the plugins to the networking.networkmanager.plugins option. That way they can be turned off if desired:

nixpkgs/nixos/modules/services/networking/networkmanager.nix

Lines 200 to 223 in 314e12b

	plugins = mkOption {
	type =
	let
	networkManagerPluginPackage = types.package // {
	description = "NetworkManager plug-in";
	check =
	p:
	lib.assertMsg
	(types.package.check p
	&& p ? networkManagerPlugin
	&& lib.isString p.networkManagerPlugin)
	''
	Package ‘${p.name}’, is not a NetworkManager plug-in.
	Those need to have a ‘networkManagerPlugin’ attribute.
	'';
	};
	in
	types.listOf networkManagerPluginPackage;
	default = [ ];
	description = ''
	List of NetworkManager plug-ins to enable.
	Some plug-ins are enabled by the NetworkManager module by default.
	'';
	};

Additional context

NetworkManager's OpenConnect plugin adds about 150MiB to my NixOS image and I don't need it so I was looking to remove it.

Metadata

❯ nix run nixpkgs#nix-info -- -m
 - system: `"x86_64-linux"`
 - host os: `Linux 6.6.63, NixOS, 24.11 (Vicuna), 24.11.20241213.314e12b`
 - multi-user?: `yes`
 - sandbox: `yes`
 - version: `nix-env (Lix, like Nix) 2.91.1
System type: x86_64-linux
Additional system types: i686-linux, x86_64-v1-linux, x86_64-v2-linux, x86_64-v3-linux, x86_64-v4-linux
Features: gc, signed-caches
System configuration file: /etc/nix/nix.conf
User configuration files: /home/jalil/.config/nix/nix.conf:/nix/store/b4q6s25biicxjzxvgqxx5hqc928ira1j-stylix-kde-config/nix/nix.conf:/etc/xdg/nix/nix.conf:/home/jalil/.local/share/flatpak/exports/etc/xdg/nix/nix.conf:/var/lib/flatpak/exports/etc/xdg/nix/nix.conf:/home/jalil/.nix-profile/etc/xdg/nix/nix.conf:/nix/profile/etc/xdg/nix/nix.conf:/home/jalil/.local/state/nix/profile/etc/xdg/nix/nix.conf:/etc/profiles/per-user/jalil/etc/xdg/nix/nix.conf:/nix/var/nix/profiles/default/etc/xdg/nix/nix.conf:/run/current-system/sw/etc/xdg/nix/nix.conf
Store directory: /nix/store
State directory: /nix/var/nix
Data directory: /nix/store/5fpjpa356qcpljidymbalqxq47yjp9lm-lix-2.91.1/share`
 - nixpkgs: `/nix/store/0xbni69flk8380w0apw4h640n37wn1i9-source

Notify maintainers

@jtojnar

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[jtojnar]

See #137338 and #164531

[jalil-salame]

Thanks!

Tl;dr: if you want to disable NetworkManager's default plugins, do this:

{
  networking.networkmanager.plugins = lib.mkForce [ ];
}