The `nix.*` options, apart from options for setting up the
daemon itself, currently provide a lot of setting mappings
for the Nix daemon configuration. The scope of the mapping yields
convience, but the line where an option is considered essential
is blurry. For instance, the `extra-sandbox-paths` mapping is
provided without its primary consumer, and the corresponding
`sandbox-paths` option is also not mapped.
The current system increases the maintenance burden as maintainers have to
closely follow upstream changes. In this case, there are two state versions
of Nix which have to be maintained collectively, with different options
avaliable.
This commit aims to following the standard outlined in RFC 42[1] to
implement a structural setting pattern. The Nix configuration is encoded
at its core as key-value pairs which maps nicely to attribute sets, making
it feasible to express in the Nix language itself. Some existing options are
kept such as `buildMachines` and `registry` which present a simplified interface
to managing the respective settings. The interface is exposed as `nix.settings`.
Legacy configurations are mapped to their corresponding options under `nix.settings`
for backwards compatibility.
Various options settings in other nixos modules and relevant tests have been
updated to use structural setting for consistency.
The generation and validation of the configration file has been modified to
use `writeTextFile` instead of `runCommand` for clarity. Note that validation
is now mandatory as strict checking of options has been pushed down to the
derivation level due to freeformType consuming unmatched options. Furthermore,
validation can not occur when cross-compiling due to current limitations.
A new option `publicHostKey` was added to the `buildMachines`
submodule corresponding to the base64 encoded public host key settings
exposed in the builder syntax. The build machine generation was subsequently
rewritten to use `concatStringsSep` for better performance by grouping
concatenations.
[1] - https://github.com/NixOS/rfcs/blob/master/rfcs/0042-config-option.md
since fc614c37c6 nixos needs access to its
own path (<nixpkgs/nixos>) to evaluate a system with documentation.
since documentation is enabled by default almost all systems need such
access, including the installer tests. nixos-install however does not
ensure that a channel exists in the target store before evaluating the
system in that store, which can lead to `path is not valid` errors.
`mktemp` tries to use the `TMPDIR` from `nixos-install` outside of the
`chroot` instead of `/tmp` inside the `chroot` and fails. For some
reason the `TMPDIR` is being passed through the `chroot` call.
I haven't tested if other environment variables are being passed through
that shouldn't be.
This commit encapsulates the involved domain into classes and
defines explicit and typed arguments where untyped dicts where used.
It preserves backwards compatibility through legacy wrappers.
so the underlaying use case of the preceding commit is so
generic, that we gain a lot in reasoning to give it an
appropriate name.
As the comment states:
image media needs to override host config short of mkForce
https://github.com/NixOS/nixpkgs/pull/131760 was made to avo
a speicific configuration conflict that errored out for multiple definitions of "/" when the installer where overlayed
on any existing host configuration.
---
Problem 1: It turns out that in also other mountpoints can coflict.
Solution 1: use `mkOverride 60` for all mountpoints (even for the ones unlikely causing confilct for consistency sake)
---
Problem 2: It turns out that on an installation media for a fresh machine (before formatting), we usually don't have any devices yet formatted. However defining for example `fileSystems.<nme>.device = "/dev/disk/by-label/...", in newer versions of nixos, seems to make the system startup fail. Similarily waiting for a non-existent swap device does not make the startup fail, but has a 1:30 min timeout.
Solution 2: For an installation medium, soft-override ("unless users know what they are doing") the entire `fileSystems` and `swapDevices` definitions.
installer media can be used on top of existing host configs. In such
scenarions, root fs types will already be defined.
Before this change, this will inevitably lead to the following error:
```console
error: The option `fileSystems./.fsType' has conflicting definition values:
- In `/nix/store/2nl5cl4mf6vnldpbxhrbzfh0n8rsv9fm-source/DevOS/os/hardware/common.nix': "ext4"
- In `/nix/store/jbch90yqx6gg1h3fq30jjj2b6h6jfjgs-source/nixos/modules/installer/cd-dvd/iso-image.nix': "tmpfs"
```
With this patch, the installers will override those values according to
their own local requirement.
Use `mkOverride 60` so that conscientious overriding specially targeted
at the installer, e.g. with `mkForce` is still straight forward.
Different boards using u-boot SPL require to write to different
locations. Sometimes, the 8MiB gap isn't sufficient - rk3399 boards
write to 0x16384 for example, which is at 8MiB, thus overriding the
fat32 partition with the SPL.
