zaphyra's git: nixfiles

config/nixos: add `dns` module

diff --git a/config/nixos/dns.nix b/config/nixos/dns.nix
@@ -0,0 +1,56 @@
+{
+  inputs,
+  dnsNix,
+  povSelf,
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+let
+  inherit (lib) types;
+  cfg = lib.getAttrFromPath povSelf config;
+
+in
+{
+
+  options = {
+    enable = {
+      type = types.bool;
+      default = false;
+    };
+
+    # contains dns entries defined on the local host
+    zones = {
+      type    = types.attrsOf dnsNix.types.subzone;
+      default = {};
+    };
+
+    # contains dns entries defined on the local host and on remote hosts, merged together
+    allZones = {
+      type    = types.attrsOf dnsNix.types.zone;
+      default = {};
+    };
+
+    zoneFiles = {
+      type    = types.attrsOf types.path;
+      readOnly = true;
+      default = (
+        cfg.allZones
+        |> lib.mapAttrs (name: zone: toString (pkgs.writeTextFile {
+          name = "${name}.zone";
+          text = dnsNix.types.zoneToString name (dnsNix.evalZone name zone);
+        }))
+      );
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    # serve records defined in all host configs
+    dns.allZones = lib.mkMerge (
+      inputs.self.nixosConfigurations
+      |> lib.mapAttrsToList (hostName: hostConfig: hostConfig.config.dns.zones)
+    );
+  };
+
+}