pkgs/dns-slaves: DRY masterAddrs

nix/pkgs/dns-slaves.nix

@@ -2,21 +2,25 @@
 
 with nixpkgs.legacyPackages.${system};
 
+let
+  servConf = self.lib.config.site.net.serv;
+  masterAddrs =
+    [servConf.hosts4.dns] ++
+    map (hosts6: hosts6.dns)
+      (builtins.attrValues servConf.hosts6);
+  mastersStr =
+    builtins.foldl' (result: addr:
+      "${result} ${addr};"
+    ) "" masterAddrs;
+in
+
 writeText "named.slave.conf" (
   lib.concatMapStringsSep "\n" ({ name, ns, ... }: ''
     zone "${name}" IN {
       type slave;
-      masters {
-        2a00:8180:2c00:282::2;
-        fd23:42:c3d2:582:2::2;
-        172.20.73.2;
-      };
+      masters {${mastersStr} };
       file "/var/lib/bind/slave/${name}.zone";
-      allow-notify {
-        2a00:8180:2c00:282::2;
-        fd23:42:c3d2:582:2::2;
-        172.20.73.2;
-      };
+      allow-notify {${mastersStr} };
     };
   '') (
     # public zones only