nixpkgs/nixos/lib/testing-python.nix
Andreas Rammhold 04100cd281
nixos/tests: restructure test driver so that QEMU is actually overriden
Previously you would be able to override only the QEMU package to be
used in the test runner. Frankly that doesn't help a lot if you are
trying to get a graphical session. The graphical session requires the
option in the NixOS module system to bet set to the correct QEMU
package.

In this commit I moved most of the test node configuration and
transformations into the `mkDriver` function (previously called
`driver`). The motivation was to be able to create a `driver` instance
with a given QEMU package that will be used consistently througout the
test expression.
2020-10-25 20:09:33 +01:00

290 lines
8.7 KiB
Nix

{ system
, pkgs ? import ../.. { inherit system config; }
# Use a minimal kernel?
, minimal ? false
# Ignored
, config ? {}
# !!! See comment about args in lib/modules.nix
, specialArgs ? {}
# Modules to add to each VM
, extraConfigurations ? [] }:
with pkgs;
rec {
inherit pkgs;
mkTestDriver = let
testDriverScript = ./test-driver/test-driver.py;
in qemu_pkg: stdenv.mkDerivation {
name = "nixos-test-driver";
nativeBuildInputs = [ makeWrapper ];
buildInputs = [ (python3.withPackages (p: [ p.ptpython ])) ];
checkInputs = with python3Packages; [ pylint black mypy ];
dontUnpack = true;
preferLocalBuild = true;
doCheck = true;
checkPhase = ''
mypy --disallow-untyped-defs \
--no-implicit-optional \
--ignore-missing-imports ${testDriverScript}
pylint --errors-only ${testDriverScript}
black --check --diff ${testDriverScript}
'';
installPhase =
''
mkdir -p $out/bin
cp ${testDriverScript} $out/bin/nixos-test-driver
chmod u+x $out/bin/nixos-test-driver
# TODO: copy user script part into this file (append)
wrapProgram $out/bin/nixos-test-driver \
--prefix PATH : "${lib.makeBinPath [ qemu_pkg vde2 netpbm coreutils ]}" \
'';
};
# Run an automated test suite in the given virtual network.
# `driver' is the script that runs the network.
runTests = driver:
stdenv.mkDerivation {
name = "vm-test-run-${driver.testName}";
requiredSystemFeatures = [ "kvm" "nixos-test" ];
buildCommand =
''
mkdir -p $out
LOGFILE=/dev/null tests='exec(os.environ["testScript"])' ${driver}/bin/nixos-test-driver
'';
};
makeTest =
{ testScript
, enableOCR ? false
, name ? "unnamed"
# Skip linting (mainly intended for faster dev cycles)
, skipLint ? false
, ...
} @ t:
let
# A standard store path to the vm monitor is built like this:
# /tmp/nix-build-vm-test-run-$name.drv-0/vm-state-machine/monitor
# The max filename length of a unix domain socket is 108 bytes.
# This means $name can at most be 50 bytes long.
maxTestNameLen = 50;
testNameLen = builtins.stringLength name;
ocrProg = tesseract4.override { enableLanguages = [ "eng" ]; };
imagemagick_tiff = imagemagick_light.override { inherit libtiff; };
# Generate convenience wrappers for running the test driver
# interactively with the specified network, and for starting the
# VMs from the command line.
mkDriver = qemu_pkg:
let
build-vms = import ./build-vms.nix {
inherit system pkgs minimal specialArgs;
extraConfigurations = extraConfigurations ++ (pkgs.lib.optional (qemu_pkg != null)
{
virtualisation.qemu.package = qemu_pkg;
}
);
};
# FIXME: get this pkg from the module system
testDriver = mkTestDriver (if qemu_pkg == null then pkgs.qemu_test else qemu_pkg);
nodes = build-vms.buildVirtualNetwork (
t.nodes or (if t ? machine then { machine = t.machine; } else { }));
vlans = map (m: m.config.virtualisation.vlans) (lib.attrValues nodes);
vms = map (m: m.config.system.build.vm) (lib.attrValues nodes);
testScript' =
# Call the test script with the computed nodes.
if lib.isFunction testScript
then testScript { inherit nodes; }
else testScript;
testDriverName = with builtins;
if testNameLen > maxTestNameLen then
abort ("The name of the test '${name}' must not be longer than ${toString maxTestNameLen} " +
"it's currently ${toString testNameLen} characters long.")
else
"nixos-test-driver-${name}";
warn = if skipLint then lib.warn "Linting is disabled!" else lib.id;
in
warn (runCommand testDriverName
{ buildInputs = [ makeWrapper];
testScript = testScript';
preferLocalBuild = true;
testName = name;
passthru = {
inherit nodes;
};
}
''
mkdir -p $out/bin
echo -n "$testScript" > $out/test-script
${lib.optionalString (!skipLint) ''
${python3Packages.black}/bin/black --check --diff $out/test-script
''}
ln -s ${testDriver}/bin/nixos-test-driver $out/bin/
vms=($(for i in ${toString vms}; do echo $i/bin/run-*-vm; done))
wrapProgram $out/bin/nixos-test-driver \
--add-flags "''${vms[*]}" \
${lib.optionalString enableOCR
"--prefix PATH : '${ocrProg}/bin:${imagemagick_tiff}/bin'"} \
--run "export testScript=\"\$(${coreutils}/bin/cat $out/test-script)\"" \
--set VLANS '${toString vlans}'
ln -s ${testDriver}/bin/nixos-test-driver $out/bin/nixos-run-vms
wrapProgram $out/bin/nixos-run-vms \
--add-flags "''${vms[*]}" \
${lib.optionalString enableOCR "--prefix PATH : '${ocrProg}/bin'"} \
--set tests 'start_all(); join_all();' \
--set VLANS '${toString vlans}' \
${lib.optionalString (builtins.length vms == 1) "--set USE_SERIAL 1"}
''); # "
passMeta = drv: drv // lib.optionalAttrs (t ? meta) {
meta = (drv.meta or {}) // t.meta;
};
driver = mkDriver null;
driverInteractive = mkDriver pkgs.qemu;
test = passMeta (runTests driver);
nodeNames = builtins.attrNames driver.nodes;
invalidNodeNames = lib.filter
(node: builtins.match "^[A-z_]([A-z0-9_]+)?$" node == null) nodeNames;
in
if lib.length invalidNodeNames > 0 then
throw ''
Cannot create machines out of (${lib.concatStringsSep ", " invalidNodeNames})!
All machines are referenced as python variables in the testing framework which will break the
script when special characters are used.
Please stick to alphanumeric chars and underscores as separation.
''
else
test // {
inherit test driver driverInteractive;
inherit (test) nodes;
};
runInMachine =
{ drv
, machine
, preBuild ? ""
, postBuild ? ""
, ... # ???
}:
let
build-vms = import ./build-vms.nix {
inherit system pkgs minimal specialArgs extraConfigurations;
};
vm = build-vms.buildVM { }
[ machine
{ key = "run-in-machine";
networking.hostName = "client";
nix.readOnlyStore = false;
virtualisation.writableStore = false;
}
];
buildrunner = writeText "vm-build" ''
source $1
${coreutils}/bin/mkdir -p $TMPDIR
cd $TMPDIR
exec $origBuilder $origArgs
'';
testScript = ''
start_all()
client.wait_for_unit("multi-user.target")
${preBuild}
client.succeed("env -i ${bash}/bin/bash ${buildrunner} /tmp/xchg/saved-env >&2")
${postBuild}
client.succeed("sync") # flush all data before pulling the plug
'';
vmRunCommand = writeText "vm-run" ''
xchg=vm-state-client/xchg
${coreutils}/bin/mkdir $out
${coreutils}/bin/mkdir -p $xchg
for i in $passAsFile; do
i2=''${i}Path
_basename=$(${coreutils}/bin/basename ''${!i2})
${coreutils}/bin/cp ''${!i2} $xchg/$_basename
eval $i2=/tmp/xchg/$_basename
${coreutils}/bin/ls -la $xchg
done
unset i i2 _basename
export | ${gnugrep}/bin/grep -v '^xchg=' > $xchg/saved-env
unset xchg
export tests='${testScript}'
${testDriver}/bin/nixos-test-driver ${vm.config.system.build.vm}/bin/run-*-vm
''; # */
in
lib.overrideDerivation drv (attrs: {
requiredSystemFeatures = [ "kvm" ];
builder = "${bash}/bin/sh";
args = ["-e" vmRunCommand];
origArgs = attrs.args;
origBuilder = attrs.builder;
});
runInMachineWithX = { require ? [], ... } @ args:
let
client =
{ ... }:
{
inherit require;
imports = [
../tests/common/auto.nix
];
virtualisation.memorySize = 1024;
services.xserver.enable = true;
test-support.displayManager.auto.enable = true;
services.xserver.displayManager.defaultSession = "none+icewm";
services.xserver.windowManager.icewm.enable = true;
};
in
runInMachine ({
machine = client;
preBuild =
''
client.wait_for_x()
'';
} // args);
simpleTest = as: (makeTest as).test;
}