Set up papermc with systemd

nki-home/configuration.nix

@@ -34,6 +34,7 @@ in
     ../modules/personal/u2f.nix
     ./peertube-runner.nix
     ./deluge.nix
+    ./minecraft.nix
     openrazer
   ];
 

nki-home/minecraft.nix

@@ -0,0 +1,103 @@
+{
+  pkgs,
+  lib,
+  ...
+}:
+let
+  dataDir = "/mnt/steam/mc/";
+  javaOpts = "-Xms4096M -Xmx4096M -XX:+AlwaysPreTouch -XX:+DisableExplicitGC -XX:+ParallelRefProcEnabled -XX:+PerfDisableSharedMem -XX:+UnlockExperimentalVMOptions -XX:+UseG1GC -XX:G1HeapRegionSize=8M -XX:G1HeapWastePercent=5 -XX:G1MaxNewSizePercent=40 -XX:G1MixedGCCountTarget=4 -XX:G1MixedGCLiveThresholdPercent=90 -XX:G1NewSizePercent=30 -XX:G1RSetUpdatingPauseTimePercent=5 -XX:G1ReservePercent=20 -XX:InitiatingHeapOccupancyPercent=15 -XX:MaxGCPauseMillis=200 -XX:MaxTenuringThreshold=1 -XX:SurvivorRatio=32 -Dusing.aikars.flags=https://mcflags.emc.gs -Daikars.new.flags=true";
+  name = "paper-mc";
+  socketName = "${name}.stdin";
+  socket = "/run/${socketName}";
+
+  console = pkgs.writeScriptBin "papermc-console" ''
+    #!${lib.getExe pkgs.python3}
+    # https://github.com/AtomicSponge/paper-systemd/blob/main/minecraft-console.py
+
+    import curses
+    import subprocess
+    import threading
+
+    def run_journalctl(win):
+        process = subprocess.Popen(['journalctl', '-u', '${name}', '--follow'], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+        while True:
+            line = process.stdout.readline()
+            if not line:
+                break
+            win.addstr(line.decode())
+            win.refresh()
+
+    def input_commands(win):
+        with open('${socket}', 'a') as f:
+            while True:
+                win.clear()
+                win.addstr("Enter command (Ctrl-C to exit): ")
+                curses.echo()
+                win.move(1, 0)
+                command = win.getstr().decode()
+                f.write(command + "\n")
+                f.flush()
+                curses.noecho()
+                win.clear()
+
+    def main(stdscr):
+        try:
+            curses.curs_set(1)
+            stdscr.clear()
+            
+            height, width = stdscr.getmaxyx()
+            journal_height = int(height * 0.9)
+            input_height = height - journal_height
+
+            journal_win = stdscr.subwin(journal_height, width, 0, 0)
+            journal_win.scrollok(True)
+            input_win = stdscr.subwin(input_height, width, journal_height, 0)
+
+            thread = threading.Thread(target=run_journalctl, args=(journal_win,))
+            thread.daemon = True
+            thread.start()
+
+            input_commands(input_win)
+            
+        except KeyboardInterrupt:
+            stdscr.clear()
+            stdscr.refresh()
+        finally:
+            curses.endwin()
+
+    if __name__ == "__main__":
+        curses.wrapper(main)
+  '';
+in
+{
+  environment.systemPackages = [ console ];
+  users.users.${name} = {
+    isSystemUser = true;
+    group = name;
+  };
+  users.users.nki.extraGroups = [ name ];
+  users.groups.${name} = {
+  };
+  systemd.sockets.${name} = {
+    partOf = [ "${name}.service" ];
+    socketConfig.ListenFIFO = "%t/${socketName}";
+  };
+  systemd.services.${name} = {
+    description = "Minecraft Server";
+    serviceConfig = {
+      Type = "simple";
+      WorkingDirectory = dataDir;
+      User = name;
+      Restart = "on-failure";
+      Sockets = "${name}.socket";
+      StandardInput = "socket";
+      StandardOutput = "journal";
+      StandardError = "journal";
+      ReadWritePaths = [ dataDir ];
+    };
+    environment.JAVA_OPTS = javaOpts;
+    script = "${lib.getExe pkgs.papermc}";
+    preStop = "echo stop > ${socket}";
+    wantedBy = [ "multi-user.target" ];
+  };
+}