docs: add generated modules readme

apps/gen-docs/getModuleMeta.nix

@@ -0,0 +1,13 @@
+attr: selfPath: let
+  inherit (builtins) mapAttrs replaceStrings;
+
+  modules = import "${selfPath}/${attr}" {description = true;};
+
+  trimNewlines = s: replaceStrings ["\n"] [" "] s;
+in {
+  attrs =
+    mapAttrs (_: v: {
+      desc = trimNewlines v;
+    })
+    modules;
+}

apps/gen-docs/script.sh

@@ -9,8 +9,20 @@ substitute() {
     ) -t markdown --template "$FLAKE/apps/gen-docs/templates/$2.md" -o "$FLAKE/$2/README.md"
 }
 
+substituteModule() {
+    echo '' | pandoc --metadata-file <(
+        nix eval \
+            --impure \
+            --json \
+            --expr "\"$FLAKE\"" \
+            --apply "(import \"$FLAKE/apps/gen-docs/getModuleMeta.nix\") \"$1\"" |
+            jq -r
+    ) -t markdown --template "$FLAKE/apps/gen-docs/templates/$1.md" -o "$FLAKE/$1/README.md"
+}
+
 # TODO: add homeManagerModules, lib, modules, nixFastChecks, overlays, scopedPackages
 substitute "appsPackages" "apps" "getPackageMeta"
 substitute "nixosConfigurations" "configurations" "getConfigMeta"
 substitute "devShells" "devShells" "getPackageMeta"
 substitute "packages" "packages" "getPackageMeta"
+substituteModule "modules"

apps/gen-docs/templates/modules.md

@@ -0,0 +1,11 @@
+# nixosModules
+
+This directory contains every modules for NixOS exposed by this flake.
+
+## List of my modules found in `self.nixosModules`
+
+| Name | Description |
+| ---- | ----------- |
+$for(attrs/pairs)$
+| `$it.key$` | $it.value.desc/nowrap$ |
+$endfor$