nixpkgs/nixos/tests/cntr.nix
Jamie McClymont 126ce87b0c nixos/tests: fix flaky cntr test
The cntr sometimes hangs until the 10-hour hydra limit. This behaviour
appears to be an edge-case related to the type of TTY in which the cntr
command runs during test execution. We can work around this by running
the command as a background job.

I additionally added a wait_for_open_port to fix nondeterministic test
failures I observed after fixing the hanging issue.
2022-03-03 19:15:10 +13:00

76 lines
2.6 KiB
Nix

# Test for cntr tool
{ system ? builtins.currentSystem, config ? { }
, pkgs ? import ../.. { inherit system config; }, lib ? pkgs.lib }:
let
inherit (import ../lib/testing-python.nix { inherit system pkgs; }) makeTest;
mkOCITest = backend:
makeTest {
name = "cntr-${backend}";
meta = { maintainers = with lib.maintainers; [ sorki mic92 ]; };
nodes = {
${backend} = { pkgs, ... }: {
environment.systemPackages = [ pkgs.cntr ];
virtualisation.oci-containers = {
inherit backend;
containers.nginx = {
image = "nginx-container";
imageFile = pkgs.dockerTools.examples.nginx;
ports = [ "8181:80" ];
};
};
};
};
testScript = ''
start_all()
${backend}.wait_for_unit("${backend}-nginx.service")
${backend}.wait_for_open_port(8181)
# For some reason, the cntr command hangs when run without the &.
# As such, we have to do some messy things to ensure we check the exitcode and output in a race-condition-safe manner
${backend}.execute(
"(cntr attach -t ${backend} nginx sh -- -c 'curl localhost | grep Hello' > /tmp/result; echo $? > /tmp/exitcode; touch /tmp/done) &"
)
${backend}.wait_for_file("/tmp/done")
assert "0" == ${backend}.succeed("cat /tmp/exitcode").strip(), "non-zero exit code"
assert "Hello" in ${backend}.succeed("cat /tmp/result"), "no greeting in output"
'';
};
mkContainersTest = makeTest {
name = "cntr-containers";
meta = with pkgs.lib.maintainers; { maintainers = [ sorki mic92 ]; };
machine = { lib, ... }: {
environment.systemPackages = [ pkgs.cntr ];
containers.test = {
autoStart = true;
privateNetwork = true;
hostAddress = "172.16.0.1";
localAddress = "172.16.0.2";
config = { };
};
};
testScript = ''
machine.start()
machine.wait_for_unit("container@test.service")
# I haven't observed the same hanging behaviour in this version as in the OCI version which necessetates this messy invocation, but it's probably better to be safe than sorry and use it here as well
machine.execute(
"(cntr attach test sh -- -c 'ping -c5 172.16.0.1'; echo $? > /tmp/exitcode; touch /tmp/done) &"
)
machine.wait_for_file("/tmp/done")
assert "0" == machine.succeed("cat /tmp/exitcode").strip(), "non-zero exit code"
'';
};
in {
nixos-container = mkContainersTest;
} // (lib.foldl' (attrs: backend: attrs // { ${backend} = mkOCITest backend; })
{ } [ "docker" "podman" ])