Add library function to read public vars

lib/default.nix

@@ -30,6 +30,8 @@ lib.fix (
       jsonschema = import ./jsonschema { inherit lib; };
       docs = import ./docs.nix { inherit lib; };
 
+      vars = import ./vars.nix { inherit lib; };
+
       # flakes
       flakes = clanLib.callLib ./flakes.nix { };
 

lib/inventory/distributed-service/all-services-wrapper.nix

@@ -37,6 +37,10 @@ in
               { name, ... }:
               {
                 _module.args._ctx = [ name ];
+                _module.args.clanLib = specialArgs.clanLib;
+                _module.args.exports = config.exports;
+                _module.args.directory = directory;
+
               }
             )
             ./service-module.nix

lib/vars.nix

@@ -0,0 +1,25 @@
+_: {
+  getPublicValue =
+    {
+
+      backend ? "in_repo",
+      default ? throw "getPublicValue: Public value ${machine}/${generator}/${file} not found!",
+      shared ? false,
+      generator,
+      machine,
+      file,
+      flake,
+    }:
+
+    if backend == "in_repo" then
+      let
+        path =
+          if shared then
+            "${flake}/vars/shared/${generator}/${file}/value"
+          else
+            "${flake}/vars/per-machine/${machine}/${generator}/${file}/value";
+      in
+      if builtins.pathExists path then builtins.readFile path else default
+    else
+      throw "backend ${backend} does not implement getPublicValue";
+}

modules/inventoryClass/inventory.nix

@@ -167,7 +167,7 @@ in
       '';
       type = types.submoduleWith {
         specialArgs = {
-          inherit (config) machines;
+          inherit (config) machines clanLib;
         };
         modules = [
           {