diff options
Diffstat (limited to 'nixos')
| -rw-r--r-- | nixos/modules/misc/label.nix | 22 |
1 files changed, 21 insertions, 1 deletions
diff --git a/nixos/modules/misc/label.nix b/nixos/modules/misc/label.nix index b4e88915d829..250914e8f82e 100644 --- a/nixos/modules/misc/label.nix +++ b/nixos/modules/misc/label.nix @@ -18,6 +18,24 @@ in If you ever wanted to influence the labels in your GRUB menu, this is the option for you. + + The default is <option>system.nixos.tags</option> separated by + "-" + "-" + <envar>NIXOS_LABEL_VERSION</envar> environment + variable (defaults to the value of + <option>system.nixos.version</option>). + + Can be overriden by setting <envar>NIXOS_LABEL</envar>. + + Useful for not loosing track of configurations built from different + nixos branches/revisions, 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_VERSION="$today.$branch-''${revision:0:7}" + nixos-rebuild switch</screen> ''; }; @@ -46,7 +64,9 @@ in config = { # This is set here rather than up there so that changing it would # not rebuild the manual - system.nixos.label = mkDefault (concatStringsSep "-" (sort (x: y: x < y) cfg.tags) + "-" + cfg.version); + system.nixos.label = mkDefault (maybeEnv "NIXOS_LABEL" + (concatStringsSep "-" (sort (x: y: x < y) cfg.tags) + + "-" + maybeEnv "NIXOS_LABEL_VERSION" cfg.version)); }; } |