nixos/ddclient: deprecate `use`, implement `use{v4,v6}`

Upstream replaced `use` with `use{v4,v6}`:
https://github.com/ddclient/ddclient/blob/4a1b06630b90b3e6ff1d837b849bdbc68a2f53f9/ChangeLog.md#new-features

2 files changed, 22 insertions, 2 deletions

diff --git a/nixos/doc/manual/release-notes/rl-2411.section.md b/nixos/doc/manual/release-notes/rl-2411.section.md
index e9ef9c2e6d5c7..93d3816d077d5 100644
--- a/nixos/doc/manual/release-notes/rl-2411.section.md
+++ b/nixos/doc/manual/release-notes/rl-2411.section.md
@@ -30,6 +30,8 @@
   `services.forgejo.secrets` is a small wrapper over systemd's `LoadCredential=`. It has the same structure (sections/keys) as
   `services.forgejo.settings` but takes file paths that will be read before service startup instead of some plaintext value.
 
+- `services.ddclient.use` has been deprecated: `ddclient` now supports separate IPv4 and IPv6 configuration. Use `services.ddclient.usev4` and `services.ddclient.usev6` instead.
+
 - The Invoiceplane module now only accepts the structured `settings` option.
   `extraConfig` is now removed.
 
diff --git a/nixos/modules/services/networking/ddclient.nix b/nixos/modules/services/networking/ddclient.nix
index b912550e1155e..272a50eb92de8 100644
--- a/nixos/modules/services/networking/ddclient.nix
+++ b/nixos/modules/services/networking/ddclient.nix
@@ -11,7 +11,9 @@ let
     # This file can be used as a template for configFile or is automatically generated by Nix options.
     cache=${dataDir}/ddclient.cache
     foreground=YES
-    use=${cfg.use}
+    ${lib.optionalString (cfg.use != "") "use=${cfg.use}"}
+    ${lib.optionalString (cfg.use == "" && cfg.usev4 != "") "usev4=${cfg.usev4}"}
+    ${lib.optionalString (cfg.use == "" && cfg.usev6 != "") "usev6=${cfg.usev6}"}
     login=${cfg.username}
     password=${if cfg.protocol == "nsupdate" then "/run/${RuntimeDirectory}/ddclient.key" else "@password_placeholder@"}
     protocol=${cfg.protocol}
@@ -163,12 +165,26 @@ with lib;
       };
 
       use = mkOption {
-        default = "web, web=checkip.dyndns.com/, web-skip='Current IP Address: '";
+        default = "";
         type = str;
         description = ''
           Method to determine the IP address to send to the dynamic DNS provider.
         '';
       };
+      usev4 = mkOption {
+        default = "webv4, webv4=checkip.dyndns.com/, webv4-skip='Current IP Address: '";
+        type = str;
+        description = ''
+          Method to determine the IPv4 address to send to the dynamic DNS provider. Only used if `use` is not set.
+        '';
+      };
+      usev6 = mkOption {
+        default = "webv6, webv6=checkipv6.dyndns.com/, webv6-skip='Current IP Address: '";
+        type = str;
+        description = ''
+          Method to determine the IPv6 address to send to the dynamic DNS provider. Only used if `use` is not set.
+        '';
+      };
 
       verbose = mkOption {
         default = false;
@@ -204,6 +220,8 @@ with lib;
   ###### implementation
 
   config = mkIf config.services.ddclient.enable {
+    warnings = lib.optional (cfg.use != "") "Setting `use` is deprecated, ddclient now supports `usev4` and `usev6` for separate IPv4/IPv6 configuration.";
+
     systemd.services.ddclient = {
       description = "Dynamic DNS Client";
       wantedBy = [ "multi-user.target" ];