nixpkgs/nixos/modules/misc/version.nix
obadz 47950b5353 modules/misc/version.nix: populate nixosRevision based on <nixpkgs/.git> when possible (#15624)
Example:

$ nixos-option system.nixosLabel
Value:
"16.09.git.4643ca1"
2016-05-24 23:34:28 +01:00

130 lines
3.9 KiB
Nix

{ config, lib, pkgs, ... }:
with lib;
let
cfg = config.system;
releaseFile = "${toString pkgs.path}/.version";
suffixFile = "${toString pkgs.path}/.version-suffix";
revisionFile = "${toString pkgs.path}/.git-revision";
gitRepo = "${toString pkgs.path}/.git";
gitCommitId = lib.substring 0 7 (commitIdFromGitRepo gitRepo);
in
{
options.system = {
stateVersion = mkOption {
type = types.str;
default = cfg.nixosRelease;
description = ''
Every once in a while, a new NixOS release may change
configuration defaults in a way incompatible with stateful
data. For instance, if the default version of PostgreSQL
changes, the new version will probably be unable to read your
existing databases. To prevent such breakage, you can set the
value of this option to the NixOS release with which you want
to be compatible. The effect is that NixOS will option
defaults corresponding to the specified release (such as using
an older version of PostgreSQL).
'';
};
nixosLabel = mkOption {
type = types.str;
description = ''
NixOS version name to be used in the names of generated
outputs and boot labels.
If you ever wanted to influence the labels in your GRUB menu,
this is option is for you.
Can be set directly or with <envar>NIXOS_LABEL</envar>
environment variable for <command>nixos-rebuild</command>,
e.g.:
<screen>
#!/bin/sh
today=`date +%Y%m%d`
branch=`(cd nixpkgs ; git branch 2>/dev/null | sed -n '/^\* / { s|^\* ||; p; }')`
revision=`(cd nixpkgs ; git rev-parse HEAD)`
export NIXOS_LABEL="$today.$branch-''${revision:0:7}"
nixos-rebuild switch</screen>
'';
};
nixosVersion = mkOption {
internal = true;
type = types.str;
description = "NixOS version.";
};
nixosRelease = mkOption {
readOnly = true;
type = types.str;
default = readFile releaseFile;
description = "NixOS release.";
};
nixosVersionSuffix = mkOption {
internal = true;
type = types.str;
default = if pathExists suffixFile then readFile suffixFile else "pre-git";
description = "NixOS version suffix.";
};
nixosRevision = mkOption {
internal = true;
type = types.str;
default = if pathExists revisionFile then readFile revisionFile else "master";
description = "NixOS Git revision hash.";
};
nixosCodeName = mkOption {
readOnly = true;
type = types.str;
description = "NixOS release code name.";
};
defaultChannel = mkOption {
internal = true;
type = types.str;
default = https://nixos.org/channels/nixos-unstable;
description = "Default NixOS channel to which the root user is subscribed.";
};
};
config = {
system = {
# These defaults are set here rather than up there so that
# changing them would not rebuild the manual
nixosLabel = mkDefault (maybeEnv "NIXOS_LABEL" cfg.nixosVersion);
nixosVersion = mkDefault (maybeEnv "NIXOS_VERSION" (cfg.nixosRelease + cfg.nixosVersionSuffix));
nixosRevision = mkIf (pathExists gitRepo) (mkDefault gitCommitId);
nixosVersionSuffix = mkIf (pathExists gitRepo) (mkDefault (".git." + gitCommitId));
# Note: code names must only increase in alphabetical order.
nixosCodeName = "Flounder";
};
# Generate /etc/os-release. See
# http://0pointer.de/public/systemd-man/os-release.html for the
# format.
environment.etc."os-release".text =
''
NAME=NixOS
ID=nixos
VERSION="${config.system.nixosVersion} (${config.system.nixosCodeName})"
VERSION_ID="${config.system.nixosVersion}"
PRETTY_NAME="NixOS ${config.system.nixosVersion} (${config.system.nixosCodeName})"
HOME_URL="http://nixos.org/"
'';
};
}