add offsite backup support to modded mc

modules/gameservers/minecraft_modded/default.nix

@@ -49,6 +49,21 @@ in {
       default = "/holocron/archives/gameservers/minecraft/modded";
       description = "path to take hourly backups to with borg!";
     };
+    offsite_user = lib.mkOption {
+      type = lib.types.str;
+      default = "lifeboat";
+      description = "user to connect to offsite host with";
+    };
+    offsite_target = lib.mkOption {
+      type = lib.types.str;
+      default = "lifeboat.holocron.blue";
+      description = "ip or domain for offsite backups";
+    };
+    offsite_dir = lib.mkOption {
+      type = lib.types.str;
+      default = "lifeboat/holocron/archives/gameservers";
+      description = "path to rsync offsite backups to";
+    };
   };
 
   config = lib.mkIf cfg.enable {
@@ -140,6 +155,13 @@ in {
       );
       compression = "auto,zstd";
       #preHook = "systemctl start mysql-backup.service";
+      postHook = ''
+        ${pkgs.sshpass}/bin/sshpass -f ${sec."lifeboat_rsync".path} \
+          ${pkgs.rsync}/bin/rsync -aHAX --partial --numeric-ids --info=progress2,name1,stats2 --delete \
+          -e "ssh -o StrictHostKeyChecking=no" \
+          ${toString cfg.backup_repo} \
+          ${cfg.offsite_user}@${cfg.offsite_target}::${cfg.offsite_dir}
+      '';
       startAt = "*-*-* *:00:00";
       group = "archives";
       encryption.mode = "repokey-blake2";