nix/tests/nixos/tarball-flakes.nix
Eelco Dolstra 1ff186fc6e nix flake metadata: Show flake fingerprint
This is useful for testing/debugging and maybe for sharing eval caches
(since it tells you what file in ~/.cache/nix/eval-cache-v5 to copy).
2024-07-03 17:00:30 +02:00

93 lines
3.3 KiB
Nix

{ lib, config, nixpkgs, ... }:
let
pkgs = config.nodes.machine.nixpkgs.pkgs;
root = pkgs.runCommand "nixpkgs-flake" {}
''
mkdir -p $out/{stable,tags}
set -x
dir=nixpkgs-${nixpkgs.shortRev}
cp -prd ${nixpkgs} $dir
# Set the correct timestamp in the tarball.
find $dir -print0 | xargs -0 touch -h -t ${builtins.substring 0 12 nixpkgs.lastModifiedDate}.${builtins.substring 12 2 nixpkgs.lastModifiedDate} --
tar cfz $out/stable/${nixpkgs.rev}.tar.gz $dir --hard-dereference
# Set the "Link" header on the redirect but not the final response to
# simulate an S3-like serving environment where the final host cannot set
# arbitrary headers.
cat >$out/tags/.htaccess <<EOF
Redirect "/tags/latest.tar.gz" "/stable/${nixpkgs.rev}.tar.gz"
Header always set Link "<http://localhost/stable/${nixpkgs.rev}.tar.gz?rev=${nixpkgs.rev}&revCount=1234>; rel=\"immutable\""
EOF
'';
in
{
name = "tarball-flakes";
nodes =
{
machine =
{ config, pkgs, ... }:
{ networking.firewall.allowedTCPPorts = [ 80 ];
services.httpd.enable = true;
services.httpd.adminAddr = "foo@example.org";
services.httpd.extraConfig = ''
ErrorLog syslog:local6
'';
services.httpd.virtualHosts."localhost" =
{ servedDirs =
[ { urlPath = "/";
dir = root;
}
];
};
virtualisation.writableStore = true;
virtualisation.diskSize = 2048;
virtualisation.additionalPaths = [ pkgs.hello pkgs.fuse ];
virtualisation.memorySize = 4096;
nix.settings.substituters = lib.mkForce [ ];
nix.extraOptions = "experimental-features = nix-command flakes";
};
};
testScript = { nodes }: ''
# fmt: off
import json
start_all()
machine.wait_for_unit("httpd.service")
out = machine.succeed("nix flake metadata --json http://localhost/tags/latest.tar.gz")
print(out)
info = json.loads(out)
# Check that we got redirected to the immutable URL.
assert info["locked"]["url"] == "http://localhost/stable/${nixpkgs.rev}.tar.gz"
# Check that we got a fingerprint for caching.
assert info["fingerprint"]
# Check that we got the rev and revCount attributes.
assert info["revision"] == "${nixpkgs.rev}"
assert info["revCount"] == 1234
# Check that fetching with rev/revCount/narHash succeeds.
machine.succeed("nix flake metadata --json http://localhost/tags/latest.tar.gz?rev=" + info["revision"])
machine.succeed("nix flake metadata --json http://localhost/tags/latest.tar.gz?revCount=" + str(info["revCount"]))
machine.succeed("nix flake metadata --json http://localhost/tags/latest.tar.gz?narHash=" + info["locked"]["narHash"])
# Check that fetching fails if we provide incorrect attributes.
machine.fail("nix flake metadata --json http://localhost/tags/latest.tar.gz?rev=493300eb13ae6fb387fbd47bf54a85915acc31c0")
machine.fail("nix flake metadata --json http://localhost/tags/latest.tar.gz?revCount=789")
machine.fail("nix flake metadata --json http://localhost/tags/latest.tar.gz?narHash=sha256-tbudgBSg+bHWHiHnlteNzN8TUvI80ygS9IULh4rklEw=")
'';
}