refactor(openwebrx): pull out common module config

modules/nixos/openwebrx.nix

@@ -0,0 +1,48 @@
+{
+  config,
+  lib,
+  ...
+}: let
+  inherit (lib.options) mkOption;
+  inherit (lib.modules) mkIf mkOptionDefault mkForce;
+  inherit (lib.trivial) mapNullable;
+  cfg = config.services.openwebrx;
+in {
+  options.services.openwebrx = with lib.types; {
+    port = mkOption {
+      type = port;
+      default = 8073;
+      readOnly = true;
+    };
+    dataDir = mkOption {
+      type = path;
+      default = "/var/lib/openwebrx";
+      readOnly = true;
+    };
+    user = mkOption {
+      type = nullOr str;
+      default = null;
+    };
+    group = mkOption {
+      type = nullOr str;
+    };
+  };
+
+  config = {
+    services.openwebrx = {
+      group = mkOptionDefault (mapNullable (user: config.users.users.${user}.group) cfg.user);
+    };
+
+    systemd.services.openwebrx = mkIf cfg.enable {
+      serviceConfig = mkIf (cfg.user != null) {
+        DynamicUser = mkForce false;
+        User = cfg.user;
+        Group = cfg.group;
+      };
+    };
+
+    environment.systemPackages = mkIf cfg.enable [
+      cfg.package
+    ];
+  };
+}