Use host and user directories for mapping outputs

README.md

@@ -1,48 +1,29 @@
-# flake-parts Module for multi-system and multi-user configuration
+# flake-parts module for multi-system and multi-user configuration
 
-ez-configs flake-parts module provides a flexible framework for managing configurations across multiple systems using nixosSystem, darwinSystem (nix-darwin), and homeManagerConfiguration (home-manager).
+ez-configs flake-parts module provides a flexible framework for managing configurations across multiple systems using nixosSystem, darwinSystem (nix-darwin), and homeManagerConfiguration (home-manager), as well as exporting individual modules.
 
 ## Overview
 
-The module allows users to define system and user-specific configurations that are automatically when present. It is designed to work with a directory structure where configurations are organized by each configuration's hostname and username.
+This module allows for defining configuration and module outputs in your flake, for use in nixos, nix-darwin and home-manager, using your directory structure.
+This results in 6 directories the module can use:
 
-It's pretty opinionated, but aims to offer a degree of customizability.
+- [nixosModules](https://flake.parts/options/ez-configs#opt-ezConfigs.nixos.modulesDirectory)
+- [nixosHosts](https://flake.parts/options/ez-configs#opt-ezConfigs.nixos.hostsDirectory)
+- [darwinModules](https://flake.parts/options/ez-configs#opt-ezConfigs.darwin.modulesDirectory)
+- [darwinHosts](https://flake.parts/options/ez-configs#opt-ezConfigs.darwin.hostsDirectory)
+- [homeModules](https://flake.parts/options/ez-configs#opt-ezConfigs.hm.modulesDirectory)
+- [users](https://flake.parts/options/ez-configs#opt-ezConfigs.hm.usersDirectory)
 
-## Features
-
-### nixosConfigurations and darwinConfigurations
-
-Those two are created in quite analogous ways. Assuming most options are kept default and `ezConfigs.root` is set to `./.`, host defined in `ezConfigs.nixos.hosts` / `ezConfigs.darwin.hosts` get created using the following modules:
-
-- `./nixos(.nix)` or `./dariwn(.nix)` respectively, if present in your root
-- `./hosts/${hostname}(.nix)` if present in your root
-
-This lets you define both platform specific and host specific configuration by simply adding nix files or directories to appropriate locations.
-You're also able to define `specialArgs` that will be passed to the appropriate system builders. A useful example would be passing in `{ inherit inputs; }`.
-That way you can access your flake inputs from inside your nixos/darwin modules. They can either be set individually for each builder using `ezConfigs.darwin.specialArgs`/ `ezConfigs.nixos.specialArgs` or globally for all configuration builders with `ezConfigs.globalArgs`.
-
-### homeManagerConfigurations
-
-It gets created using each user and system pair, with a name `${username}@${hostname}`. Users are defined in `ezConfigs.hs.users`, while hosts are all the nixos and darwin configuration.
-With the same assumptions as in the above section, the home manager configuration gets created using the package set of generated by the host system and using the following modules:
-
-- `./home(.nix)` if present in your root
-- `./home/darwin(.nix)` or `./home/linux(.nix)` respectively, if present in your root
-- `./users/${username}(.nix)` if present in your root
-- `./users/${username}/darwin(.nix)` or `./users/${username}/linux(.nix)` respectively, if present in your root
-
-This lets you define user and platform specific configurations in the same manner as with nixos and darwin configurations. You can also pass in `extraSpecialArgs` which are the equivalent of `specialArgs` of system builders.
-
-## Goals
-
-Some of these are features that I'd like to look into, with no guarantee they get implemented since I'm not sure about how ergonomic to use they would be.
-
-- Automatically discover hosts and users when a file is created the appropriate directory
-- Allow for loading home manager as a nixos module when specified in user config, rather than creating a `homeManagerConfigurations` output
-- More configurability, like architecture dependent imports, changing the default `${username}@${hostname}` home manager configuration names, etc.
-- Extracting individual modules to flake outputs, so that then can be consumed by other flakes.
+Each `.nix` file, or a directory containing `default.nix` file gets included in the respective outputs.
+When building configurations, the default module (ie. `<modulesDirectory>/default.nix` or `<modulesDirectory>/default/default.nix`) is imported, unless `importDefault` is set to `false` for that user or host configuration.
+In case of home manager configurations, it also includes the `darwin` or `linux` modules depending on the system that configuration is built from.
 
 ## Usage
 
 See the [example directory](https://github.com/ehllie/ez-configs/blob/main/example/flake.nix) for a documented example.
 I also use this module in my [own dotfiles](https://github.com/ehllie/dotfiles/blob/main/flake.nix).
+
+## TODO
+
+- Allow for loading home manager as a nixos module when specified in user config, rather than creating a `homeManagerConfigurations` output
+- Warn when configuring users or hosts that are not present in the directory tree.

example/flake.nix

@@ -42,9 +42,6 @@
  ezConfigs = {
  root = ./.;
  globalArgs = { inherit inputs; };
- hm.users.example-user = { };
- nixos.hosts.example-nixos.arch = "x86_64";
- darwin.hosts.example-darwin.arch = "aarch64";
  };
  };
 }

flake-module.nix

@@ -1,33 +1,40 @@
 { darwin, home-manager, nixpkgs, ... }: { lib, config, ... }:
 let
 
- inherit (builtins) pathExists readDir readFileType;
+ inherit (builtins) pathExists readDir readFileType elemAt;
  inherit (nixpkgs.lib) mkOption types nixosSystem optionals literalExpression mapAttrs concatMapAttrs;
  inherit (nixpkgs.lib.strings) hasSuffix removeSuffix;
  inherit (darwin.lib) darwinSystem;
  inherit (home-manager.lib) homeManagerConfiguration;
  cfg = config.ezConfigs;
 
  # Creates an attrset of nixosConfigurations or darwinConfigurations.
- systemsWith = { systemBuilder, systemSuffix, ezModules, hostModules, specialArgs }: hosts:
+ systemsWith = { systemBuilder, systemSuffix, ezModules, hostModules, specialArgs, defaultHost }: hosts:
  mapAttrs
- (name: { arch, importDefault }: systemBuilder {
- specialArgs = specialArgs // { inherit ezModules; };
- system = "${arch}-${systemSuffix}";
- modules = [ (hostModules.${name} or { }) ]
- ++ optionals importDefault [ (ezModules.default or { }) ];
- })
- hosts;
+ (name: configModule:
+ let
+ hostSettings = hosts.${name} or defaultHost;
+ inherit (hostSettings) arch importDefault;
+ in
+ systemBuilder {
+ specialArgs = specialArgs // { inherit ezModules; };
+ system = "${arch}-${systemSuffix}";
+ modules = [ configModule ]
+ ++ optionals importDefault [ (ezModules.default or { }) ];
+ })
+ hostModules;
 
  allHosts =
  (config.flake.nixosConfigurations //
  config.flake.darwinConfigurations);
 
  # Creates an attrset of home manager confgurations for each user on each host.
- userConfigs = { ezModules, userModules, extraSpecialArgs }: users:
+ userConfigs = { ezModules, userModules, extraSpecialArgs, defaultUser }: users:
  concatMapAttrs
- (user: { importDefault, nameFunction }:
+ (user: configModule:
  let
+ userSettings = users.${user} or defaultUser;
+ inherit (userSettings) nameFunction importDefault;
  mkName =
  if nameFunction == null
  then host: "${user}@${host}"
@@ -50,7 +57,7 @@ let
  };
  })
  allHosts)
- users;
+ userModules;
 
  readModules = dir:
  if pathExists "${dir}.nix" && readFileType "${dir}.nix" == "regular" then
@@ -71,18 +78,38 @@ let
  else { }
  ;
 
- hostOptions.options = {
- arch = mkOption {
- type = types.enum [ "x86_64" "aarch64" ];
- description = "The architecture of the system.";
- };
+ # This is a workaround the types.attrsOf (type.submodule ...) functionality.
+ # We can't ensure that each host/ user present in the appropriate directory
+ # is also present in the attrset, so we need to create a default module for it.
+ # That way we can fallback to it if it's not present in the attrset.
+ # Is there a better way to do this? Maybe defining a custom type?
+ defaultSubmodule = submodule:
+ concatMapAttrs
+ (opt: optDef:
+ if optDef ? default then
+ { ${opt} = optDef.default; }
+ else { })
+ submodule.options;
 
- importDefault = mkOption {
- default = true;
- type = types.bool;
- description = ''
- Whether to import the default module for this host.
- '';
+ # Getting the first submodule seems to work, but not sure if it's the best way.
+ defaultSubmoduleAttr = attrsType:
+ defaultSubmodule (elemAt attrsType.getSubModules 0);
+
+ hostOptions = defaultArch: {
+ options = {
+ arch = mkOption {
+ type = types.enum [ "x86_64" "aarch64" ];
+ default = defaultArch;
+ description = "The architecture of the system.";
+ };
+
+ importDefault = mkOption {
+ default = true;
+ type = types.bool;
+ description = ''
+ Whether to import the default module for this host.
+ '';
+ };
  };
  };
 
@@ -106,48 +133,52 @@ let
  };
  };
 
- hostsOptions = system: {
- modulesDirectory = mkOption {
- default = "${cfg.root}/${system}";
- defaultText = literalExpression "\"\${ezConfigs.root}/${system}\"";
- type = types.pathInStore;
- description = ''
- The directory in which to look for ${system} modules.
- '';
- };
+ hostsOptions = system:
+ let
+ defaultArch = if system == "darwin" then "aarch64" else "x86_64";
+ in
+ {
+ modulesDirectory = mkOption {
+ default = "${cfg.root}/${system}";
+ defaultText = literalExpression "\"\${ezConfigs.root}/${system}\"";
+ type = types.pathInStore;
+ description = ''
+ The directory in which to look for ${system} modules.
+ '';
+ };
 
- hostsDirectory = mkOption {
- default = "${cfg.root}/hosts";
- defaultText = literalExpression "\"\${ezConfigs.root}/hosts\"";
- type = types.pathInStore;
- description = ''
- The directory in which to look for host ${system} configurations.
- '';
- };
+  hostsDirectory = mkOption {
+  default = "${cfg.root}/${system}-hosts";
+  defaultText = literalExpression "\"\${ezConfigs.root}/${system}-hosts\"";
+  type = types.pathInStore;
+  description = ''
+  The directory in which to look for host ${system} configurations.
+  '';
+  };
 
- specialArgs = mkOption {
- default = cfg.globalArgs;
- defaultText = literalExpression "ezConfigs.globalArgs";
- type = types.attrsOf types.anything;
- description = ''
- Extra arguments to pass to all ${system} configurations.
- '';
- };
+  specialArgs = mkOption {
+  default = cfg.globalArgs;
+  defaultText = literalExpression "ezConfigs.globalArgs";
+  type = types.attrsOf types.anything;
+  description = ''
+  Extra arguments to pass to all ${system} configurations.
+  '';
+  };
 
- hosts = mkOption {
- default = { };
- type = types.attrsOf (types.submodule hostOptions);
- example = literalExpression ''
- {
- hostA.arch = "x86_64";
- hostB.arch = "aarch64";
- }
- '';
- description = ''
- An attribute set of ${system} host definitions to create configurations for.
- '';
+ hosts = mkOption {
+ default = { };
+ type = types.attrsOf (types.submodule (hostOptions defaultArch));
+ example = literalExpression ''
+ {
+ hostA.arch = "x86_64";
+ hostB.arch = "aarch64";
+ }
+ '';
+ description = ''
+ An attribute set of ${system} host definitions to create configurations for.
+ '';
+ };
  };
- };
 
 in
 {
@@ -198,7 +229,7 @@ in
  };
 
  users = mkOption {
- default = [ ];
+ default = { };
  type = types.attrsOf (types.submodule userOptions);
 
  example = literalExpression ''
@@ -227,6 +258,7 @@ in
  homeConfigurations = userConfigs
  {
  userModules = readModules cfg.hm.usersDirectory;
+ defaultUser = defaultSubmodule userOptions;
  ezModules = homeModules;
  inherit (cfg.hm) extraSpecialArgs;
  }
@@ -237,6 +269,7 @@ in
  systemBuilder = nixosSystem;
  systemSuffix = "linux";
  hostModules = readModules cfg.nixos.hostsDirectory;
+ defaultHost = defaultSubmoduleAttr ((hostsOptions "nixos").hosts.type);
  ezModules = nixosModules;
  inherit (cfg.nixos)
  specialArgs;
@@ -248,6 +281,7 @@ in
  systemBuilder = darwinSystem;
  systemSuffix = "darwin";
  hostModules = readModules cfg.darwin.hostsDirectory;
+ defaultHost = defaultSubmoduleAttr ((hostsOptions "darwin").hosts.type);
  ezModules = darwinModules;
  inherit (cfg.darwin) specialArgs;
  }

flake.nix

@@ -37,11 +37,6 @@
  inherit flakeModule;
  };
 
- ezConfigs = {
- root = ./example;
- hm.users.example-user = { };
- nixos.hosts.example-nixos.arch = "x86_64";
- darwin.hosts.example-darwin.arch = "aarch64";
- };
+ ezConfigs.root = ./example;
  };
 }