stockholm/krebs/3modules/fetchWallpaper.nix
makefu 1c17881aed k 3 fetchWallpaper: change predicate handling
a failed predicate does not result in a failed system service
it will just not download the remote
2015-12-13 13:50:39 +01:00

90 lines
2.0 KiB
Nix

{ config, lib, pkgs, ... }:
with lib;
let
cfg = config.krebs.fetchWallpaper;
out = {
options.krebs.fetchWallpaper = api;
config = mkIf cfg.enable imp;
};
api = {
enable = mkEnableOption "fetch wallpaper";
predicate = mkOption {
type = with types; nullOr path;
default = null;
};
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 = ":11";
};
};
fetchWallpaperScript = pkgs.writeScript "fetchWallpaper" ''
#! ${pkgs.bash}/bin/bash
${optionalString (cfg.predicate != null) ''
if ! ${cfg.predicate}; then
echo "predicate failed - will not fetch from remote"
exit 0
fi
''}
mkdir -p ${shell.escape cfg.stateDir}
curl -s -o ${shell.escape cfg.stateDir}/wallpaper -z ${shell.escape cfg.stateDir}/wallpaper ${shell.escape cfg.url}
feh --no-fehbg --bg-scale ${shell.escape cfg.stateDir}/wallpaper
'';
imp = {
users.users.fetchWallpaper = {
name = "fetchWallpaper";
uid = 3332383611; #genid fetchWallpaper
description = "fetchWallpaper user";
home = cfg.stateDir;
createHome = true;
};
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";
};
};
};
in out