Merge pull request 'refactor: buildClan output; output deferred modules instead of nixosConfig' (#3323) from hsjobeki/clan-core:lib-cleanup into main

Reviewed-on: https://git.clan.lol/clan/clan-core/pulls/3323

lib/build-clan/inner-module.nix

@@ -1,67 +0,0 @@
-{
-  system,
-  name,
-  pkgs,
-  extraConfig,
-  config,
-  clan-core,
-}:
-{
-  _class,
-  lib,
-  ...
-}:
-let
-  inherit (config) directory machines pkgsForSystem;
-  inherit (config.clanInternals) inventoryClass;
-in
-{
-  imports = [
-    {
-      imports = builtins.filter builtins.pathExists (
-        [
-          "${directory}/machines/${name}/configuration.nix"
-        ]
-        ++ lib.optionals (_class == "nixos") [
-          "${directory}/machines/${name}/hardware-configuration.nix"
-          "${directory}/machines/${name}/disko.nix"
-        ]
-      );
-    }
-    (lib.optionalAttrs (_class == "nixos") {
-      imports = [
-        clan-core.nixosModules.clanCore
-      ] ++ (inventoryClass.machines.${name}.machineImports or [ ]);
-
-      config = {
-        clan.core.settings = {
-          inherit (config.inventory.meta) name icon;
-
-          inherit directory;
-          machine = {
-            inherit name;
-          };
-        };
-        # Inherited from clan wide settings
-        # TODO: remove these
-      };
-    })
-    extraConfig
-    (machines.${name} or { })
-    (
-      {
-        networking.hostName = lib.mkDefault name;
-
-        # For vars we need to override the system so we run vars
-        # generators on the machine that runs `clan vars generate`. If a
-        # users is using the `pkgsForSystem`, we don't set
-        # nixpkgs.hostPlatform it would conflict with the `nixpkgs.pkgs`
-        # option.
-        nixpkgs.hostPlatform = lib.mkIf (system != null && (pkgsForSystem system) != null) (
-          lib.mkForce system
-        );
-      }
-      // lib.optionalAttrs (pkgs != null) { nixpkgs.pkgs = lib.mkForce pkgs; }
-    )
-  ];
-}

lib/build-clan/machineModules/forName.nix

@@ -0,0 +1,38 @@
+{
+  name,
+  directory,
+  meta,
+}:
+{
+  _class,
+  lib,
+  ...
+}:
+{
+  imports = [
+    {
+      imports = builtins.filter builtins.pathExists (
+        [
+          "${directory}/machines/${name}/configuration.nix"
+        ]
+        ++ lib.optionals (_class == "nixos") [
+          "${directory}/machines/${name}/hardware-configuration.nix"
+          "${directory}/machines/${name}/disko.nix"
+        ]
+      );
+    }
+    (lib.optionalAttrs (_class == "nixos") {
+      clan.core.settings = {
+        inherit (meta) name icon;
+        inherit directory;
+        machine = {
+          inherit name;
+        };
+      };
+    })
+    # TODO: move into nixos modules
+    ({
+      networking.hostName = lib.mkDefault name;
+    })
+  ];
+}

lib/build-clan/machineModules/overridePkgs.nix

@@ -0,0 +1,17 @@
+{
+  pkgs,
+}:
+{
+  lib,
+  ...
+}:
+{
+  imports = [
+    ({
+      # For vars we need to ensure that the system so we run vars generate on
+      # is in sync with the pkgs of the system
+      nixpkgs.hostPlatform = lib.mkForce pkgs.system;
+      nixpkgs.pkgs = lib.mkForce pkgs;
+    })
+  ];
+}

lib/build-clan/module.nix

@@ -11,10 +11,9 @@ let
     directory
     pkgsForSystem
     specialArgs
+    inventory
     ;
 
-  inherit (config.clanInternals) inventory;
-
   inherit (clan-core.clanLib.inventory) buildInventory;
 
   supportedSystems = [
@@ -50,74 +49,24 @@ let
 
   moduleSystemConstructor = {
     # TODO: remove default system once we have a hardware-config mechanism
-    nixos =
-      {
-        system ? null,
-        name,
-        pkgs ? null,
-        extraConfig ? { },
-      }:
-      nixpkgs.lib.nixosSystem {
-        modules =
-          let
-            module = lib.modules.importApply ./inner-module.nix {
-              inherit
-                system
-                name
-                pkgs
-                extraConfig
-                config
-                clan-core
-                ;
-            };
-          in
-          [
-            module
-            {
-              config.clan.core.module = module;
-            }
-          ];
-
-        specialArgs = {
-          inherit clan-core;
-        } // specialArgs;
-      };
-
-    darwin =
-      {
-        system ? null,
-        name,
-        pkgs ? null,
-        extraConfig ? { },
-      }:
-      nix-darwin.lib.darwinSystem {
-        modules = [
-          (lib.modules.importApply ./inner-module.nix {
-            inherit
-              system
-              name
-              pkgs
-              extraConfig
-              config
-              clan-core
-              ;
-          })
-        ];
-
-        specialArgs = {
-          inherit clan-core;
-        } // specialArgs;
-      };
+    nixos = nixpkgs.lib.nixosSystem;
+    darwin = nix-darwin.lib.darwinSystem;
   };
 
-  allMachines = inventoryClass.machines;
+  allMachines = inventoryClass.machines; # <- inventory.machines <- clan.machines
 
   machineClasses = lib.mapAttrs (
     name: _: inventory.machines.${name}.machineClass or "nixos"
   ) allMachines;
 
   configurations = lib.mapAttrs (
-    name: _: moduleSystemConstructor.${machineClasses.${name}} { inherit name; }
+    name: _:
+    moduleSystemConstructor.${machineClasses.${name}} {
+      modules = [ (config.outputs.moduleForMachine.${name} or { }) ];
+      specialArgs = {
+        inherit clan-core;
+      } // specialArgs;
+    }
   ) allMachines;
 
   nixosConfigurations = lib.filterAttrs (name: _: machineClasses.${name} == "nixos") configurations;
@@ -133,8 +82,15 @@ let
         lib.mapAttrs (
           name: _:
           moduleSystemConstructor.${machineClasses.${name}} {
-            inherit name system;
-            pkgs = pkgsFor.${system};
+            modules = [
+              (config.outputs.moduleForMachine.${name} or { })
+              (lib.modules.importApply ./machineModules/overridePkgs.nix {
+                pkgs = pkgsFor.${system};
+              })
+            ];
+            specialArgs = {
+              inherit clan-core;
+            } // specialArgs;
           }
         ) allMachines
       )
@@ -152,6 +108,43 @@ let
 in
 {
   imports = [
+    {
+      options.outputs.moduleForMachine = lib.mkOption {
+        type = lib.types.attrsOf lib.types.deferredModule;
+      };
+      config.outputs.moduleForMachine = lib.mkMerge [
+        # Create one empty module for each machine such that there is a default for each machine
+        # See: 'staticModules' in the moduleForMachine option
+        # This is only necessary because clan.machines doesn't include all machines
+        # There can other sources: i.e. inventory
+        (lib.mapAttrs (
+          name: v:
+          (
+            { _class, ... }:
+            {
+              imports = (v.machineImports or [ ]) ++ [
+                (lib.modules.importApply ./machineModules/forName.nix {
+                  inherit (config.inventory) meta;
+                  inherit
+                    name
+                    directory
+                    ;
+                })
+                # Import the correct 'core' module
+                # We assume either:
+                # - nixosModules (_class = nixos)
+                # - darwinModules (_class = darwin)
+                (lib.optionalAttrs (clan-core."${_class}Modules" ? clanCore) clan-core."${_class}Modules".clanCore)
+              ];
+            }
+          )
+        ) inventoryClass.machines)
+
+        # The user can define some machine config here
+        # i.e. 'clan.machines.jon = ...'
+        config.machines
+      ];
+    }
     # Merge the inventory file
     {
       inventory = _: {