barman: Add wrapper script, minimum redundancy and backup max age

machines/loki/barman.nix

@@ -23,6 +23,9 @@
         streaming_archiver = true;
         backup_method = "postgres";
         slot_name = "barman";
+        bandwidth_limit = 0;
+        last_backup_maximum_age = "3 DAYS";
+        minimum_redundancy = 3;
         retention_policy = "RECOVERY WINDOW OF 4 WEEKS";
       };
     };

modules/barman/default.nix

@@ -9,6 +9,27 @@ let
   iniFormat = pkgs.formats.ini { };
   defaultUser = "barman";
   defaultHome = "/var/lib/barman";
+
+  runtimeInputs = with pkgs; [
+    cfg.package
+    bash
+    bzip2
+    gzip
+    lz4
+    pigz
+    postgresql
+    zstd
+  ];
+
+  barmanWrapper = pkgs.writeShellApplication {
+    name = "bm";
+
+    inherit runtimeInputs;
+
+    text = ''
+      sudo --set-home --user ${cfg.settings.barman.barman_user} -- ${cfg.package}/bin/barman "$@"
+    '';
+  };
 in
 {
   options.services.barman = {
@@ -73,7 +94,10 @@ in
           };
         }) cfg.servers);
 
-      systemPackages = [ cfg.package ];
+      systemPackages = [
+        cfg.package
+        barmanWrapper
+      ];
     };
     systemd = {
       timers.barman = {
@@ -87,16 +111,7 @@ in
 
       services.barman = {
         description = "Run barman maintenance tasks";
-        path = with pkgs; [
+        path = runtimeInputs;
-          cfg.package
-          bash
-          bzip2
-          gzip
-          lz4
-          pigz
-          postgresql
-          zstd
-        ];
         # environment = {
         #   PGPASSFILE = lib.mkIf (cfg.passwordsFile != null) cfg.passwordsFile;
         # };