stockholm/krebs/3modules/fetchWallpaper.nix
2021-10-23 12:08:58 +02:00

96 lines
2.2 KiB
Nix

{ config, lib, pkgs, ... }:
with import <stockholm/lib>;
let
cfg = config.krebs.fetchWallpaper;
out = {
options.krebs.fetchWallpaper = api;
config = lib.mkIf cfg.enable imp;
};
api = {
enable = mkEnableOption "fetch wallpaper";
url = mkOption {
type = types.str;
};
timerConfig = mkOption {
type = types.unspecified;
default = {
OnCalendar = "*:00,10,20,30,40,50";
};
};
stateDir = mkOption {
type = types.str;
default = "/var/lib/wallpaper";
};
display = mkOption {
type = types.str;
default = ":${toString config.services.xserver.display}";
};
unitConfig = mkOption {
type = types.attrsOf types.str;
description = "Extra unit configuration for fetchWallpaper to define conditions and assertions for the unit";
example = literalExample ''
# do not start when running on umts
{ ConditionPathExists = "!/var/run/ppp0.pid"; }
'';
default = {};
};
};
fetchWallpaperScript = pkgs.writeDash "fetchWallpaper" ''
set -euf
mkdir -p ${cfg.stateDir}
chmod o+rx ${cfg.stateDir}
cd ${cfg.stateDir}
(curl -s -o wallpaper.tmp -z wallpaper.tmp ${shell.escape cfg.url} && cp wallpaper.tmp wallpaper) || :
feh --no-fehbg --bg-scale wallpaper
'';
imp = {
users.users.fetchWallpaper = {
name = "fetchWallpaper";
uid = genid_uint31 "fetchWallpaper";
description = "fetchWallpaper user";
group = "fetchWallpaper";
home = cfg.stateDir;
createHome = true;
isSystemUser = true;
};
users.groups.fetchWallpaper = {};
systemd.timers.fetchWallpaper = {
description = "fetch wallpaper timer";
wantedBy = [ "timers.target" ];
timerConfig = cfg.timerConfig;
};
systemd.services.fetchWallpaper = {
description = "fetch wallpaper";
after = [ "network.target" ];
path = with pkgs; [
curl
feh
];
environment = {
URL = cfg.url;
DISPLAY = cfg.display;
};
restartIfChanged = true;
serviceConfig = {
Type = "simple";
ExecStart = fetchWallpaperScript;
User = "fetchWallpaper";
};
unitConfig = cfg.unitConfig;
};
};
in out