fix(extranix): ensure default entry exists and escape html

machines/nixos/compute01/extranix/default.nix

@@ -92,7 +92,7 @@ in
         title = "DGNum module documentation";
         languageCode = "en-us";
         params = {
-          release_current_stable = "infra-DGNum";
+          release_current_stable = "DGNum-Infrastructure";
           logo = "images/dgnum.png";
           footer_credits_line = ''
             Based on <a href="https://github.com/mipmip/home-manager-option-search">Home Manager Option Search</a>

modules/nixos/extranix/default.nix

@@ -12,6 +12,8 @@ let
   inherit (lib)
     attrNames
     concatMapStringsSep
+    concatStringsSep
+    escapeXML
     filter
     getExe
     hasPrefix
@@ -20,6 +22,7 @@ let
     importJSON
     mapAttrs'
     mapAttrsToList
+    mkDefault
     mkEnableOption
     mkIf
     mkOption
@@ -100,13 +103,13 @@ let
             type
             readOnly
             loc
-            description
             ;
           descriptionHTML = pkgs.runCommand "option-${title}.html" { } ''
-            ${getExe pkgs.pandoc} -f markdown ${pkgs.writeText "option-${title}.md" val.description} > $out
+            ${getExe pkgs.pandoc} -f markdown-raw_html ${pkgs.writeText "option-${title}.md" val.description} > $out
           '';
-          example = val.example.text or "";
-          default = val.default.text or "";
+          description = escapeXML val.description;
+          example = escapeXML (val.example.text or "");
+          default = escapeXML (val.default.text or "");
           declarations = map path-translation val.declarations;
         }) filtered-opts;
       };
@@ -238,13 +241,14 @@ in
   };
   config = mkIf cfg.enable {
     services = {
-      extranix = {
-        settings = {
-          theme = "extranix-options-search";
-          params.releases = mapAttrsToList (name: _: {
+      extranix.settings = {
+        theme = "extranix-options-search";
+        params = {
+          releases = mapAttrsToList (name: _: {
             inherit name;
             value = sanitizeDerivationName name;
           }) cfg.modules;
+          release_current_stable = mkDefault (head (attrNames options-files));
         };
       };
       nginx = {
@@ -252,5 +256,21 @@ in
         virtualHosts.${cfg.host}.locations."/".alias = "${webroot}/";
       };
     };
+    assertions = [
+      {
+        assertion = cfg.modules != { };
+        message = ''
+          `services.extranix` can't be enabled without any modules to document.
+        '';
+      }
+      {
+        assertion = options-files ? ${cfg.settings.params.release_current_stable};
+        message = ''
+          `services.extranix.settings.params.release_current_stable` should be the
+          `sanitizeDerivationName` of a key of `services.extranix.modules`, here one of:
+            + ${concatStringsSep "\n  + " (attrNames options-files)}
+        '';
+      }
+    ];
   };
 }