nixos/tzupdate: make it actually work (#343748)

nixos/modules/services/misc/tzupdate.nix

@@ -30,16 +30,15 @@ in {
       description = "tzupdate timezone update service";
       wants = [ "network-online.target" ];
       after = [ "network-online.target" ];
+      script = ''
+        timedatectl set-timezone $(${lib.getExe pkgs.tzupdate} --print-only)
+      '';
 
       serviceConfig = {
         Type = "oneshot";
-        # We could link directly into pkgs.tzdata, but at least timedatectl seems
-        # to expect the symlink to point directly to a file in etc.
-        # Setting the "debian timezone file" to point at /dev/null stops it doing anything.
-        ExecStart = "${pkgs.tzupdate}/bin/tzupdate -z /etc/zoneinfo -d /dev/null";
       };
     };
   };
 
-  meta.maintainers = [ ];
+  meta.maintainers = with lib.maintainers; [ doronbehar ];
 }

pkgs/applications/misc/tzupdate/default.nix

@@ -11,18 +11,21 @@ rustPlatform.buildRustPackage rec {
   src = fetchFromGitHub {
     owner = "cdown";
     repo = "tzupdate";
-    rev = version;
+    rev = "refs/tags/${version}";
     hash = "sha256-eod4yFzX7pATNQmG7jU+r9mnC9nprJ55ufMXpKjw/YI=";
   };
 
   cargoHash = "sha256-5+lp5xlwJxFDqzVxptJPX7z0iLoMkgdwHxvRVIXHF7Y=";
 
-  meta = with lib; {
+  meta = {
     description = "Set the system timezone based on IP geolocation";
     homepage = "https://github.com/cdown/tzupdate";
-    license = licenses.mit;
-    maintainers = with maintainers; [ camillemndn ];
-    platforms = platforms.linux;
+    license = lib.licenses.mit;
+    maintainers = with lib.maintainers; [
+      camillemndn
+      doronbehar
+    ];
+    platforms = lib.platforms.linux;
     mainProgram = "tzupdate";
   };
 }