services.xserver.xautolock: add module

nixos/modules/module-list.nix

@@ -610,6 +610,7 @@
   ./services/x11/window-managers/windowlab.nix
   ./services/x11/window-managers/wmii.nix
   ./services/x11/window-managers/xmonad.nix
+  ./services/x11/xautolock.nix
   ./services/x11/xbanish.nix
   ./services/x11/xfs.nix
   ./services/x11/xserver.nix

nixos/modules/services/x11/xautolock.nix

@@ -0,0 +1,72 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+let
+  cfg = config.services.xserver.xautolock;
+in
+  {
+    options = {
+      services.xserver.xautolock = {
+        enable = mkEnableOption "xautolock";
+        enableNotifier = mkEnableOption "xautolock.notify" // {
+          description = ''
+            Whether to enable the notifier feature of xautolock.
+            This publishes a notification before the autolock.
+          '';
+        };
+
+        time = mkOption {
+          default = 15;
+          type = types.int;
+
+          description = ''
+            Idle time to wait until xautolock locks the computer.
+          '';
+        };
+
+        locker = mkOption {
+          default = "xlock"; # default according to `man xautolock`
+          example = "i3lock -i /path/to/img";
+          type = types.string;
+
+          description = ''
+            The script to use when locking the computer.
+          '';
+        };
+
+        notify = mkOption {
+          default = 10;
+          type = types.int;
+
+          description = ''
+            Time (in seconds) before the actual lock when the notification about the pending lock should be published.
+          '';
+        };
+
+        notifier = mkOption {
+          default = "notify-send 'Locking in 10 seconds'";
+          type = types.string;
+
+          description = ''
+            Notification script to be used to warn about the pending autolock.
+          '';
+        };
+      };
+    };
+
+    config = mkIf cfg.enable {
+      environment.systemPackages = with pkgs; [ xautolock ];
+
+      services.xserver.displayManager.sessionCommands = with builtins; with pkgs; ''
+        ${xautolock}/bin/xautolock \
+          ${concatStringsSep " \\\n" ([
+            "-time ${toString(cfg.time)}"
+            "-locker ${cfg.locker}"
+          ] ++ optional cfg.enableNotifier (concatStringsSep " " [ 
+            "-notify ${toString(cfg.notify)}"
+            "-notifier \"${cfg.notifier}\""
+          ]))} &
+      '';
+    };
+  }