nixos/corerad: add settings option to supersede configFile

Signed-off-by: Matt Layher <mdlayher@gmail.com>

2 files changed, 67 insertions, 11 deletions

diff --git a/nixos/modules/services/networking/corerad.nix b/nixos/modules/services/networking/corerad.nix
index 1a2c4aec665..2d4d414aae1 100644
--- a/nixos/modules/services/networking/corerad.nix
+++ b/nixos/modules/services/networking/corerad.nix
@@ -4,14 +4,48 @@ with lib;
 
 let
   cfg = config.services.corerad;
+
+  writeTOML = name: x:
+    pkgs.runCommandNoCCLocal name { } ''
+      echo '${builtins.toJSON x}' | ${pkgs.go-toml}/bin/jsontoml > $out
+    '';
+
 in {
-  meta = {
-    maintainers = with maintainers; [ mdlayher ];
-  };
+  meta.maintainers = with maintainers; [ mdlayher ];
 
   options.services.corerad = {
     enable = mkEnableOption "CoreRAD IPv6 NDP RA daemon";
 
+    settings = mkOption {
+      type = types.uniq types.attrs;
+      example = literalExample ''
+        {
+          interfaces = [
+            # eth0 is an upstream interface monitoring for IPv6 router advertisements.
+            {
+              name = "eth0";
+              monitor = true;
+            }
+            # eth1 is a downstream interface advertising IPv6 prefixes for SLAAC.
+            {
+              name = "eth1";
+              advertise = true;
+              prefix = [{ prefix = "::/64"; }];
+            }
+          ];
+          # Optionally enable Prometheus metrics.
+          debug = {
+            address = "localhost:9430";
+            prometheus = true;
+          };
+        }
+      '';
+      description = ''
+        Configuration for CoreRAD, see <link xlink:href="https://github.com/mdlayher/corerad/blob/master/internal/config/default.toml"/>
+        for supported values. Ignored if configFile is set.
+      '';
+    };
+
     configFile = mkOption {
       type = types.path;
       example = literalExample "\"\${pkgs.corerad}/etc/corerad/corerad.toml\"";
@@ -27,6 +61,9 @@ in {
   };
 
   config = mkIf cfg.enable {
+    # Prefer the config file over settings if both are set.
+    services.corerad.configFile = mkDefault (writeTOML "corerad.toml" cfg.settings);
+
     systemd.services.corerad = {
       description = "CoreRAD IPv6 NDP RA daemon";
       after = [ "network.target" ];
diff --git a/nixos/tests/corerad.nix b/nixos/tests/corerad.nix
index 741fa448f68..72ab255b191 100644
--- a/nixos/tests/corerad.nix
+++ b/nixos/tests/corerad.nix
@@ -3,7 +3,7 @@ import ./make-test-python.nix (
     nodes = {
       router = {config, pkgs, ...}: { 
         config = {
-          # This machines simulates a router with IPv6 forwarding and a static IPv6 address.
+          # This machine simulates a router with IPv6 forwarding and a static IPv6 address.
           boot.kernel.sysctl = {
             "net.ipv6.conf.all.forwarding" = true;
           };
@@ -14,13 +14,25 @@ import ./make-test-python.nix (
             enable = true;
             # Serve router advertisements to the client machine with prefix information matching
             # any IPv6 /64 prefixes configured on this interface.
-            configFile = pkgs.writeText "corerad.toml" ''
-              [[interfaces]]
-              name = "eth1"
-              advertise = true
-                [[interfaces.prefix]]
-                prefix = "::/64"
-            '';
+            #
+            # This configuration is identical to the example in the CoreRAD NixOS module.
+            settings = {
+              interfaces = [
+                {
+                  name = "eth0";
+                  monitor = true;
+                }
+                {
+                  name = "eth1";
+                  advertise = true;
+                  prefix = [{ prefix = "::/64"; }];
+                }
+              ];
+              debug = {
+                address = "localhost:9430";
+                prometheus = true;
+              };
+            };
           };
         };
       };
@@ -66,5 +78,12 @@ import ./make-test-python.nix (
           assert (
               "/64 scope global temporary" in addrs
           ), "SLAAC temporary address was not configured on client after router advertisement"
+
+      with subtest("Verify HTTP debug server is configured"):
+          out = router.succeed("curl localhost:9430/metrics")
+
+          assert (
+              "corerad_build_info" in out
+          ), "Build info metric was not found in Prometheus output"
     '';
   })