nix/tests/remote-builds.nix
aszlig 5cfdf16dd6
Convert VM tests to Python
Perl-based tests are deprecated since NixOS 20.03 and subsequently got
removed in NixOS 20.09, which effectively means that tests are going to
fail as soon as we build it with NixOS 20.09 or anything newer.

I've put "# fmt: off" at the start of every testScript, because
formatting with Black really messes up indentation and I don't think it
really adds anything in value or readability for inlined Python scripts.

Signed-off-by: aszlig <aszlig@nix.build>
2020-10-17 23:32:03 +02:00

112 lines
3.5 KiB
Nix

# Test Nix's remote build feature.
{ nixpkgs, system, overlay }:
with import (nixpkgs + "/nixos/lib/testing-python.nix") {
inherit system;
extraConfigurations = [ { nixpkgs.overlays = [ overlay ]; } ];
};
makeTest (
let
# The configuration of the remote builders.
builder =
{ config, pkgs, ... }:
{ services.openssh.enable = true;
virtualisation.writableStore = true;
nix.useSandbox = true;
};
# Trivial Nix expression to build remotely.
expr = config: nr: pkgs.writeText "expr.nix"
''
let utils = builtins.storePath ${config.system.build.extraUtils}; in
derivation {
name = "hello-${toString nr}";
system = "i686-linux";
PATH = "''${utils}/bin";
builder = "''${utils}/bin/sh";
args = [ "-c" "if [ ${toString nr} = 5 ]; then echo FAIL; exit 1; fi; echo Hello; mkdir $out $foo; cat /proc/sys/kernel/hostname > $out/host; ln -s $out $foo/bar; sleep 10" ];
outputs = [ "out" "foo" ];
}
'';
in
{
nodes =
{ builder1 = builder;
builder2 = builder;
client =
{ config, lib, pkgs, ... }:
{ nix.maxJobs = 0; # force remote building
nix.distributedBuilds = true;
nix.buildMachines =
[ { hostName = "builder1";
sshUser = "root";
sshKey = "/root/.ssh/id_ed25519";
system = "i686-linux";
maxJobs = 1;
}
{ hostName = "builder2";
sshUser = "root";
sshKey = "/root/.ssh/id_ed25519";
system = "i686-linux";
maxJobs = 1;
}
];
virtualisation.writableStore = true;
virtualisation.pathsInNixDB = [ config.system.build.extraUtils ];
nix.binaryCaches = lib.mkForce [ ];
programs.ssh.extraConfig = "ConnectTimeout 30";
};
};
testScript = { nodes }: ''
# fmt: off
import subprocess
start_all()
# Create an SSH key on the client.
subprocess.run([
"${pkgs.openssh}/bin/ssh-keygen", "-t", "ed25519", "-f", "key", "-N", ""
], capture_output=True, check=True)
client.succeed("mkdir -p -m 700 /root/.ssh")
client.copy_from_host("key", "/root/.ssh/id_ed25519")
client.succeed("chmod 600 /root/.ssh/id_ed25519")
# Install the SSH key on the builders.
client.wait_for_unit("network.target")
for builder in [builder1, builder2]:
builder.succeed("mkdir -p -m 700 /root/.ssh")
builder.copy_from_host("key.pub", "/root/.ssh/authorized_keys")
builder.wait_for_unit("sshd")
client.succeed(f"ssh -o StrictHostKeyChecking=no {builder.name} 'echo hello world'")
# Perform a build and check that it was performed on the builder.
out = client.succeed(
"nix-build ${expr nodes.client.config 1} 2> build-output",
"grep -q Hello build-output"
)
builder1.succeed(f"test -e {out}")
# And a parallel build.
paths = client.succeed(r'nix-store -r $(nix-instantiate ${expr nodes.client.config 2})\!out $(nix-instantiate ${expr nodes.client.config 3})\!out')
out1, out2 = paths.split()
builder1.succeed(f"test -e {out1} -o -e {out2}")
builder2.succeed(f"test -e {out1} -o -e {out2}")
# And a failing build.
client.fail("nix-build ${expr nodes.client.config 5}")
# Test whether the build hook automatically skips unavailable builders.
builder1.block()
client.succeed("nix-build ${expr nodes.client.config 4}")
'';
})