nixpkgs/nixos/tests/hydra/common.nix
Maximilian Bosch bd5324c4fc
hydra: 2020-02-06 -> 2020-03-{24,27}
Upgrades Hydra to the latest master/flake branch. To perform this
upgrade, it's needed to do a non-trivial db-migration which provides a
massive performance-improvement[1].

The basic ideas behind multi-step upgrades of services between NixOS versions
have been gathered already[2]. For further context it's recommended to
read this first.

Basically, the following steps are needed:

* Upgrade to a non-breaking version of Hydra with the db-changes
  (columns are still nullable here). If `system.stateVersion` is set to
  something older than 20.03, the package will be selected
  automatically, otherwise `pkgs.hydra-migration` needs to be used.

* Run `hydra-backfill-ids` on the server.

* Deploy either `pkgs.hydra-unstable` (for Hydra master) or
  `pkgs.hydra-flakes` (for flakes-support) to activate the optimization.

The steps are also documented in the release-notes and in the module
using `warnings`.

`pkgs.hydra` has been removed as latest Hydra doesn't compile with
`pkgs.nixStable` and to ensure a graceful migration using the newly
introduced packages.

To verify the approach, a simple vm-test has been added which verifies
the migration steps.

[1] https://github.com/NixOS/hydra/pull/711
[2] https://github.com/NixOS/nixpkgs/pull/82353#issuecomment-598269471
2020-03-28 23:33:25 +01:00

47 lines
1.4 KiB
Nix

{ system, ... }:
{
baseConfig = { pkgs, ... }: let
trivialJob = pkgs.writeTextDir "trivial.nix" ''
{ trivial = builtins.derivation {
name = "trivial";
system = "${system}";
builder = "/bin/sh";
allowSubstitutes = false;
preferLocalBuild = true;
args = ["-c" "echo success > $out; exit 0"];
};
}
'';
createTrivialProject = pkgs.stdenv.mkDerivation {
name = "create-trivial-project";
dontUnpack = true;
buildInputs = [ pkgs.makeWrapper ];
installPhase = "install -m755 -D ${./create-trivial-project.sh} $out/bin/create-trivial-project.sh";
postFixup = ''
wrapProgram "$out/bin/create-trivial-project.sh" --prefix PATH ":" ${pkgs.stdenv.lib.makeBinPath [ pkgs.curl ]} --set EXPR_PATH ${trivialJob}
'';
};
in {
virtualisation.memorySize = 2048;
time.timeZone = "UTC";
environment.systemPackages = [ createTrivialProject pkgs.jq ];
services.hydra = {
enable = true;
# Hydra needs those settings to start up, so we add something not harmfull.
hydraURL = "example.com";
notificationSender = "example@example.com";
extraConfig = ''
email_notification = 1
'';
};
services.postfix.enable = true;
nix = {
buildMachines = [{
hostName = "localhost";
systems = [ system ];
}];
binaryCaches = [];
};
};
}