ryan4yin | 二花
cf6c657e4a
* refactor: consume computer-use packages from NUR * fix: expose flake inputs to package overlays Package overlays are imported from two places with different argument shapes: outputs/default.nix passes a set containing `inputs`, while modules/base/overlays.nix passes the NixOS module args, where genSpecialArgs spreads each flake input as a top-level argument. The new NUR-backed overlays read `inputs.nur-ryan4yin`, so evaluation failed on the module path. Also expose the whole flake input set as `inputs` in genSpecialArgs. * chore: bump nur-ryan4yin input Update the locked nur-packages revision to the current main (nixpkgs 26.05, unused packages removed).
Flake Outputs
Is such a complex and fine-grained structure necessary?
There is no need to do this when you have a small number of machines.
But when you have a large number of machines, it is necessary to manage them in a fine-grained way, otherwise, it will be difficult to manage and maintain them.
The number of my machines has grown past a dozen, and the increase in scale has shown signs of getting out of control of complexity, so it is a natural and reasonable choice to use this fine-grained architecture to manage.
Tests
Testing is not necessary when your configuration is not complex, but with the increase in the number and configuration of your machines, testing becomes more and more important.
We have two types of tests: eval tests and nixos tests, both of which can help us detect many obscure errors early, so as to avoid testing directly in the real world, and to avoid failures in personal computers and even corporate online environments.
Related projects & docs:
- haumea: Filesystem-based module system for Nix
- Unveiling the Power of the NixOS Integration Test Driver (Part 1)
- NixOS Tests - NixOS Manual
1. Eval Tests
Eval Tests evaluate the expressions and compare the results with the expected results. It runs fast, but it doesn't build a real machine. We use eval tests to ensure that some attributes are correctly set for each NixOS and nix-darwin host.
How to run all the eval tests:
nix eval .#evalTests --show-trace --print-build-logs --verbose
Each test is a directory outputs/<system>/tests/<name>/ holding expr.nix and expected.nix; the
suite passes when every expr equals its expected.
Which tests cover a new host
Some tests iterate over every configuration, so a new host is covered automatically and must satisfy them. Others name specific hosts and only cover a new host if you add it.
| Kind | Tests |
|---|---|
| Every configuration | hostname, kernel, nix-system-features, security-apparmor, security-container-groups, security-exporters, security-firewall, security-k3s-kubeconfig, security-kernel, security-ssh-x11 |
| Named hosts only | btrbk, home-manager, home-manager-xdg, computer-use-headless, k3s-api-endpoint, k3s-master-home-manager, idols-ai-gpu, youko-metrics, ups-metrics, shoukei-logind |
hostname expects each configuration's networking.hostName to equal its name. Niri desktop
configurations are the exception (ai-niri → ai, shoukei-niri → shoukei) and are listed in
specialExpected in that platform's hostname/expected.nix.
2. NixOS Tests
WIP: not working yet
NixOS Tests builds and starts virtual machines using our NixOS configuration and run tests on them. Comparing to eval tests, it runs slow, but it builds a real machine, and we can test the whole system actually works as expected.
Problems:
- We need a private cache server, so that our NixOS tests do not need to build some custom packages every time we run the tests.
- Cannot test the whole host, because my host relies on its unique ssh host key to decrypt its
agenix secrets.
- Maybe it's better to test every service separately, not the whole host?
How to run a host's NixOS tests:
# Format: nix build .#<name>-nixos-tests
nix build .#ruby-nixos-tests
Only ruby currently defines a *-nixos-tests output.
Overview
All the outputs of this flake are defined here.
› tree
.
├── default.nix # The entry point, all the outputs are composed here.
├── README.md
├── aarch64-darwin # All outputs for macOS Apple Silicon
│ ├── default.nix
│ ├── src # every host has its own file in this directory
│ │ ├── fern.nix
│ │ └── frieren.nix
│ └── tests # eval tests
├── aarch64-linux # All outputs for Linux ARM64
│ ├── default.nix
│ ├── src # every host has its own file in this directory
│ │ ├── 12kingdoms-shoukei.nix
│ │ └── idols-akane.nix
│ └── tests # eval tests
└── x86_64-linux # All outputs for Linux x86_64
├── default.nix
├── nixos-tests
├── src # every host has its own file in this directory
│ ├── 12kingdoms-shoryu.nix
│ ├── 12kingdoms-shushou.nix
│ ├── 12kingdoms-youko.nix
│ ├── idols-ai.nix
│ ├── idols-kana.nix
│ ├── idols-ruby.nix
│ ├── k3s-test-1-master-1.nix
│ ├── k3s-test-1-master-2.nix
│ ├── k3s-test-1-master-3.nix
│ ├── k3s-test-1-worker-1.nix
│ ├── k3s-test-1-worker-2.nix
│ └── k3s-test-1-worker-3.nix
└── tests # eval tests (btrbk, computer-use-headless, hostname,
# kernel, security-*, ups-metrics, ...)