nixos/noctalia-greeter: init

nixos/modules/module-list.nix

@@ -637,6 +637,7 @@
   ./services/display-managers/greetd.nix
   ./services/display-managers/lemurs.nix
   ./services/display-managers/ly.nix
+  ./services/display-managers/noctalia-greeter.nix
   ./services/display-managers/plasma-login-manager.nix
   ./services/display-managers/regreet.nix
   ./services/display-managers/sddm.nix

nixos/modules/services/display-managers/noctalia-greeter.nix

@@ -0,0 +1,130 @@
+# adapted from upstream
+{
+  lib,
+  pkgs,
+  config,
+  ...
+}:
+let
+  cfg = config.services.displayManager.noctalia-greeter;
+  format = pkgs.formats.toml { };
+
+  inherit (lib)
+    escapeShellArgs
+    getExe'
+    maintainers
+    mkDefault
+    mkEnableOption
+    mkIf
+    mkOption
+    mkPackageOption
+    optionalAttrs
+    ;
+
+  inherit (lib.types)
+    listOf
+    str
+    ;
+in
+{
+  options.services.displayManager.noctalia-greeter = {
+    enable = mkEnableOption "Noctalia Greeter, a minimal login greeter for greetd";
+
+    package = mkPackageOption pkgs "noctalia-greeter" { };
+
+    extraArgs = mkOption {
+      description = "Arguments to add to the noctalia-greeter-session invocation.";
+      type = listOf str;
+      default = [ ];
+    };
+
+    settings = mkOption {
+      description = ''
+        Settings for noctalia-greeter written to greeter.toml.
+
+        Note that it also can contain some state, like the most recently used
+        session, which will be clobbered on every activation and boot. This is
+        due to an upstream limitation; the state is due to be moved to another
+        file.
+      '';
+      inherit (format) type;
+      default = { };
+      example = {
+        cursor = {
+          theme = "Adwaita";
+          size = 24;
+        };
+        keyboard = {
+          layout = "us";
+        };
+      };
+    };
+
+    cursorTheme = {
+      package = mkPackageOption pkgs "cursor theme" {
+        nullable = true;
+        default = null;
+      };
+
+      name = mkOption {
+        type = str;
+        default = "Adwaita";
+        description = ''
+          Name of the cursor theme to use for noctalia-greeter.
+        '';
+      };
+    };
+  };
+
+  config =
+    let
+      user = config.services.greetd.settings.default_session.user;
+      group =
+        let
+          g = config.users.users.${user}.group or "";
+        in
+        if g != "" then g else "greeter";
+    in
+    mkIf cfg.enable {
+      assertions = [
+        {
+          assertion = (config.users.users.${user} or { }) != { };
+          message = "noctalia-greeter: user ${user} does not exist. Please create it before referencing it.";
+        }
+      ];
+
+      services.displayManager.noctalia-greeter.settings.cursor = mkIf (cfg.cursorTheme.package != null) {
+        theme = mkDefault cfg.cursorTheme.name;
+        path = mkDefault "${cfg.cursorTheme.package}/share/icons";
+      };
+
+      environment.systemPackages = [ cfg.package ];
+
+      systemd.tmpfiles.settings."10-noctalia-greeter" = {
+        "/var/lib/noctalia-greeter".d = {
+          inherit user group;
+          mode = "0750";
+        };
+      }
+      // optionalAttrs (cfg.settings != { }) {
+        "/var/lib/noctalia-greeter/greeter.toml"."L+" = {
+          argument = "${format.generate "greeter.toml" cfg.settings}";
+          inherit user group;
+          mode = "0644";
+        };
+      };
+
+      services.greetd = {
+        enable = mkDefault true;
+        settings.default_session.command = mkDefault "${getExe' cfg.package "noctalia-greeter-session"} ${escapeShellArgs cfg.extraArgs}";
+      };
+
+      security.polkit.enable = mkDefault true;
+      services.accounts-daemon.enable = mkDefault true;
+    };
+
+  meta.maintainers = with maintainers; [
+    dtomvan
+    samiser
+  ];
+}