feat(nixos): add Palworld Tracion guest

configs/nixos/guests/palworld.nix

@@ -0,0 +1,146 @@
+{
+  config,
+  lib,
+  ...
+}:
+let
+  cfg = config.guests.palworld;
+  steamDir = "/data/steamcmd";
+  installDir = "/data/server";
+  stateDir = "/data/state";
+in
+{
+  options.guests.palworld = {
+    steamPath = lib.mkOption {
+      type = lib.types.nullOr lib.types.str;
+      default = null;
+      example = "/srv/steamcmd";
+      description = "Host path bind-mounted as SteamCMD's metadata directory.";
+    };
+
+    installPath = lib.mkOption {
+      type = lib.types.nullOr lib.types.str;
+      default = null;
+      example = "/srv/palworld/server";
+      description = "Host path bind-mounted as Palworld's server install directory.";
+    };
+
+    statePath = lib.mkOption {
+      type = lib.types.nullOr lib.types.str;
+      default = null;
+      example = "/srv/palworld/state";
+      description = "Host path bind-mounted as Palworld's durable state directory.";
+    };
+
+    serverName = lib.mkOption {
+      type = lib.types.str;
+      default = "palworld";
+      description = "Name shown for the Palworld server.";
+    };
+
+    port = lib.mkOption {
+      type = lib.types.port;
+      default = 8211;
+      description = "UDP port for the Palworld server.";
+    };
+
+    publicIP = lib.mkOption {
+      type = lib.types.nullOr lib.types.str;
+      default = null;
+      description = "Public IP address advertised by the Palworld server.";
+    };
+
+    passwordSecret = lib.mkOption {
+      type = lib.types.str;
+      default = "services/game-servers/password";
+      description = "SOPS secret name containing the Palworld server password.";
+    };
+
+    adminPasswordSecret = lib.mkOption {
+      type = lib.types.str;
+      default = "services/game-servers/password";
+      description = "SOPS secret name containing the Palworld admin password.";
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    assertions = [
+      {
+        assertion = cfg.steamPath != null;
+        message = "guests.palworld.steamPath must point at the host directory that stores SteamCMD metadata.";
+      }
+      {
+        assertion = cfg.installPath != null;
+        message = "guests.palworld.installPath must point at the host directory that stores Palworld server files.";
+      }
+      {
+        assertion = cfg.statePath != null;
+        message = "guests.palworld.statePath must point at the host directory that stores Palworld durable state.";
+      }
+    ];
+
+    guests.palworld = {
+      interior.modules.services.games.palworld = {
+        enable = true;
+        inherit (cfg) serverName port publicIP;
+        inherit steamDir installDir stateDir;
+        passwordFile = "/run/secrets/${cfg.passwordSecret}";
+        adminPasswordFile = "/run/secrets/${cfg.adminPasswordSecret}";
+      };
+
+      mounts =
+        {
+          ${steamDir} = {
+            directory = cfg.steamPath;
+            owner = config.registry."stable-uid".${config.networking.hostName}.steamcmd;
+            group = "storage";
+            mode = "0770";
+          };
+          ${installDir} = {
+            directory = cfg.installPath;
+            owner = config.registry."stable-uid".${config.networking.hostName}.steamcmd;
+            group = "storage";
+            mode = "0770";
+          };
+          ${stateDir} = {
+            directory = cfg.statePath;
+            owner = config.registry."stable-uid".${config.networking.hostName}.steamcmd;
+            group = "storage";
+            mode = "0770";
+          };
+          ${"/run/secrets/${cfg.passwordSecret}"} = {
+            file = config.sops.secrets.${cfg.passwordSecret}.path;
+            readOnly = true;
+          };
+        }
+        // lib.optionalAttrs (cfg.adminPasswordSecret != cfg.passwordSecret) {
+          ${"/run/secrets/${cfg.adminPasswordSecret}"} = {
+            file = config.sops.secrets.${cfg.adminPasswordSecret}.path;
+            readOnly = true;
+          };
+        };
+
+      limits = {
+        memory = lib.mkDefault "8G";
+        cpu = lib.mkDefault "400%";
+        tasksMax = lib.mkDefault 2048;
+      };
+    };
+
+    sops.secrets =
+      {
+        ${cfg.passwordSecret} = {
+          owner = "root";
+          group = "storage";
+          mode = "0440";
+        };
+      }
+      // lib.optionalAttrs (cfg.adminPasswordSecret != cfg.passwordSecret) {
+        ${cfg.adminPasswordSecret} = {
+          owner = "root";
+          group = "storage";
+          mode = "0440";
+        };
+      };
+  };
+}