forked from extern/nixos-installer
44 lines
1.6 KiB
Markdown
44 lines
1.6 KiB
Markdown
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# NixOS Modules
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A NixOS module is a collection of any number of NixOS option definitions and value assignments to those or other options.
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While the set of imported modules, and thereby that of the defined options, is static (in this case starting with the modules passed to `mkNixosSystem` in `../flake.nix`), the value assignments can generally be contingent on other values (as long as there are no logical loops), making for highly flexible system constructions.
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Since modules can't be imported (or excluded) dynamically, most modules have an `enable` option, which, if false, effectively disables whatever that module does.
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Ultimately, the goal of a NixOS configuration is to build an operating system, which is basically a structured collection of program and configuration files.
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To that end, there are a number of pre-defined options (in `nixpkgs`) that collect programs, create and write configuration files (primarily in `/etc`), compose a boot loader, etc.
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Other modules use those options to manipulate how the system is built.
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## Template
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Here is a skeleton structure for writing a new `<module>.nix.md`:
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````md
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/*
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# TODO: title
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TODO: documentation
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## Implementation
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```nix
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#*/# end of MarkDown, beginning of NixOS module:
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dirname: inputs: { config, pkgs, lib, ... }: let lib = inputs.self.lib.__internal__; in let
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prefix = inputs.config.prefix;
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cfg = config.${prefix}.${TODO: name};
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in {
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options.${prefix} = { ${TODO: name} = {
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enable = lib.mkEnableOption "TODO: what";
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# TODO: more options
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}; };
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config = lib.mkIf cfg.enable (lib.mkMerge [ ({
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# TODO: implementation
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}) ]);
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}
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````
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