nixos-repl-setup

This is a small utility that defines a payload, that, when loaded in your nix repl session, will prepopulate useful variables from your NixOS configuration

Usage

The main function is under repl-setup if imported as a flake.

It takes these arguments:

source: A URL or file path to the system configuration
isUrl: Whether source is a flake URL
If this is unset, most URLs will fail
plainImport: Whether to disregard flake.nix and always use import
passExtra: A list of attributes to pass through
This uses a special format to navigate attrsets. A string will be interpreted as an attribute, a list of attributes as an attribute path, and a list of a string and another list as a renamed attribute path.
If you’re using a flake this is with respect to the flake itself. If not, with respect to the configuration (called system).
By default, flakes passthrough inputs.nixpkgs, and inputs.nixpkgs.lib. By default, non-flakes passthrough pkgs.lib. (pkgs is always passed)

Flake-only arguments:

hostname: What hostname the desired configuration is under. Otherwise it will select the first, alphabetically.

Example

Save this as an easily accesible file (e.g. ~/repl.nix):

let nixos-repl-setup = builtins.getFlake "github:schuelermine/nixos-repl-setup/ce5bc68652d489ebeccb6cd867b4a2c7ce669da3";
in nixos-repl-setup.repl-setup {
    hostname = "GigueMowHeadGrape";
    source = "git+file:///etc/nixos/";
    isUrl = true;
    passExtra = [ [ "l" [ "inputs" "nixpkgs" "lib" ] ] [ "inputs" "MyFlake" "fubar" "egg" ] ];
}

You can also clone the repository and use the folder directly.
For instance, I have this in ~/repl.nix:

let repl-setup = import ./Code/nixos-repl-setup;
in repl-setup { source = "git+file:///etc/nixos"; isUrl = true; } // builtins