feat(nixos): add Palworld Tracion guest

configs/nixos/modules/services/games/palworld.nix

@@ -0,0 +1,148 @@
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+{
+  options.modules.services.games.palworld = {
+    enable = lib.mkEnableOption "Palworld dedicated server";
+
+    steamDir = lib.mkOption {
+      type = lib.types.str;
+      example = "/data/steamcmd";
+      description = "Directory where SteamCMD stores metadata and cache files.";
+    };
+
+    installDir = lib.mkOption {
+      type = lib.types.str;
+      example = "/data/servers/palworld/tracion";
+      description = "Directory where SteamCMD installs the Palworld server files.";
+    };
+
+    stateDir = lib.mkOption {
+      type = lib.types.str;
+      example = "/data/state/palworld/tracion";
+      description = "Directory where Palworld stores durable server state.";
+    };
+
+    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.";
+    };
+
+    maxPlayers = lib.mkOption {
+      type = lib.types.ints.between 1 32;
+      default = 32;
+      description = "Maximum player count for the Palworld server.";
+    };
+
+    publicLobby = lib.mkOption {
+      type = lib.types.bool;
+      default = true;
+      description = "Advertise the server in Palworld's public lobby.";
+    };
+
+    rcon = {
+      enable = lib.mkEnableOption "Palworld RCON" // {
+        default = true;
+      };
+
+      port = lib.mkOption {
+        type = lib.types.port;
+        default = 25575;
+        description = "TCP port for Palworld RCON.";
+      };
+    };
+
+    passwordFile = lib.mkOption {
+      type = lib.types.path;
+      description = "Runtime file containing the Palworld server password.";
+    };
+
+    adminPasswordFile = lib.mkOption {
+      type = lib.types.path;
+      description = "Runtime file containing the Palworld admin password.";
+    };
+  };
+
+  config = lib.mkIf config.modules.services.games.palworld.enable (
+    let
+      service = config.modules.services.games.palworld;
+      savedDir = "${service.installDir}/Pal/Saved";
+      startScript = pkgs.writeShellScript "palworld-start" ''
+        set -eu
+
+        ${pkgs.coreutils}/bin/install -d \
+          -m 0770 \
+          ${lib.escapeShellArg service.stateDir} \
+          ${lib.escapeShellArg (builtins.dirOf savedDir)}
+
+        if [ -L ${lib.escapeShellArg savedDir} ]; then
+          current_target="$(${pkgs.coreutils}/bin/readlink ${lib.escapeShellArg savedDir})"
+          if [ "$current_target" != ${lib.escapeShellArg service.stateDir} ]; then
+            ${pkgs.coreutils}/bin/rm ${lib.escapeShellArg savedDir}
+          fi
+        fi
+
+        if [ -d ${lib.escapeShellArg savedDir} ] && [ ! -L ${lib.escapeShellArg savedDir} ]; then
+          if ${pkgs.findutils}/bin/find ${lib.escapeShellArg service.stateDir} -mindepth 1 -maxdepth 1 | ${pkgs.gnugrep}/bin/grep -q .; then
+            ${pkgs.coreutils}/bin/rm -rf ${lib.escapeShellArg savedDir}
+          else
+            ${pkgs.coreutils}/bin/cp -a ${lib.escapeShellArg savedDir}/. ${lib.escapeShellArg service.stateDir}/
+            ${pkgs.coreutils}/bin/rm -rf ${lib.escapeShellArg savedDir}
+          fi
+        fi
+
+        if [ ! -e ${lib.escapeShellArg savedDir} ]; then
+          ${pkgs.coreutils}/bin/ln -s ${lib.escapeShellArg service.stateDir} ${lib.escapeShellArg savedDir}
+        fi
+
+        password="$(${pkgs.coreutils}/bin/tr -d '\n' < ${lib.escapeShellArg service.passwordFile})"
+        admin_password="$(${pkgs.coreutils}/bin/tr -d '\n' < ${lib.escapeShellArg service.adminPasswordFile})"
+
+        exec ./PalServer.sh \
+          "$@" \
+          "-serverpassword=$password" \
+          "-adminpassword=$admin_password"
+      '';
+    in
+    {
+      modules.services.steamcmd = {
+        enable = true;
+        inherit (service) steamDir installDir stateDir;
+        serviceName = "palworld-${lib.toLower service.serverName}";
+        appId = 2394010;
+        executable = "${startScript}";
+        arguments =
+          [
+            "-useperfthreads"
+            "-NoAsyncLoadingThread"
+            "-UseMultithreadForDS"
+            "-port=${toString service.port}"
+            "-publicport=${toString service.port}"
+            "-servername=${service.serverName}"
+            "-players=${toString service.maxPlayers}"
+          ]
+          ++ lib.optional service.publicLobby "-publiclobby"
+          ++ lib.optionals (service.publicIP != null) [ "-publicip=${service.publicIP}" ]
+          ++ lib.optional service.rcon.enable "-rcon";
+        udpPorts = [ service.port ];
+        tcpPorts = [ service.port ];
+      };
+    }
+  );
+}

configs/nixos/modules/services/steamcmd.nix

@@ -59,6 +59,12 @@
       default = [ ];
       description = "UDP ports opened for the game service.";
     };
+
+    tcpPorts = lib.mkOption {
+      type = lib.types.listOf lib.types.port;
+      default = [ ];
+      description = "TCP ports opened for the game service.";
+    };
   };
 
   config = lib.mkMerge [
@@ -159,6 +165,7 @@
         };
 
         networking.firewall.allowedUDPPorts = service.udpPorts;
+        networking.firewall.allowedTCPPorts = service.tcpPorts;
       }
     ))
   ];