nixpkgs/nixos/tests/docker-tools.nix
Louis Blin b3f68289df dockerTools.streamLayeredImage: resolve duplicate env vars
For images running on Kubernetes, there is no guarantee on how duplicate
environment variables in the image config will be handled. This seems
to be different from Docker, where the last environment variable value
is consistently selected.

The current code for `streamLayeredImage` was exploiting that assumption
to easily propagate environment variables from the base image, leaving
duplicates unchecked. It should rather resolve these duplicates to
ensure consistent behavior on Docker and Kubernetes.
2021-03-25 23:29:54 +00:00

318 lines
13 KiB
Nix

# this test creates a simple GNU image with docker tools and sees if it executes
import ./make-test-python.nix ({ pkgs, ... }: {
name = "docker-tools";
meta = with pkgs.lib.maintainers; {
maintainers = [ lnl7 ];
};
nodes = {
docker = { ... }: {
virtualisation = {
diskSize = 2048;
docker.enable = true;
};
};
};
testScript = with pkgs.dockerTools; ''
unix_time_second1 = "1970-01-01T00:00:01Z"
docker.wait_for_unit("sockets.target")
with subtest("Ensure Docker images use a stable date by default"):
docker.succeed(
"docker load --input='${examples.bash}'"
)
assert unix_time_second1 in docker.succeed(
"docker inspect ${examples.bash.imageName} "
+ "| ${pkgs.jq}/bin/jq -r .[].Created",
)
docker.succeed("docker run --rm ${examples.bash.imageName} bash --version")
# Check imageTag attribute matches image
docker.succeed("docker images --format '{{.Tag}}' | grep -F '${examples.bash.imageTag}'")
docker.succeed("docker rmi ${examples.bash.imageName}")
# The remaining combinations
with subtest("Ensure imageTag attribute matches image"):
docker.succeed(
"docker load --input='${examples.bashNoTag}'"
)
docker.succeed(
"docker images --format '{{.Tag}}' | grep -F '${examples.bashNoTag.imageTag}'"
)
docker.succeed("docker rmi ${examples.bashNoTag.imageName}:${examples.bashNoTag.imageTag}")
docker.succeed(
"docker load --input='${examples.bashNoTagLayered}'"
)
docker.succeed(
"docker images --format '{{.Tag}}' | grep -F '${examples.bashNoTagLayered.imageTag}'"
)
docker.succeed("docker rmi ${examples.bashNoTagLayered.imageName}:${examples.bashNoTagLayered.imageTag}")
docker.succeed(
"${examples.bashNoTagStreamLayered} | docker load"
)
docker.succeed(
"docker images --format '{{.Tag}}' | grep -F '${examples.bashNoTagStreamLayered.imageTag}'"
)
docker.succeed(
"docker rmi ${examples.bashNoTagStreamLayered.imageName}:${examples.bashNoTagStreamLayered.imageTag}"
)
docker.succeed(
"docker load --input='${examples.nixLayered}'"
)
docker.succeed("docker images --format '{{.Tag}}' | grep -F '${examples.nixLayered.imageTag}'")
docker.succeed("docker rmi ${examples.nixLayered.imageName}")
with subtest(
"Check if the nix store is correctly initialized by listing "
"dependencies of the installed Nix binary"
):
docker.succeed(
"docker load --input='${examples.nix}'",
"docker run --rm ${examples.nix.imageName} nix-store -qR ${pkgs.nix}",
"docker rmi ${examples.nix.imageName}",
)
with subtest(
"Ensure (layered) nix store has correct permissions "
"and that the container starts when its process does not have uid 0"
):
docker.succeed(
"docker load --input='${examples.bashLayeredWithUser}'",
"docker run -u somebody --rm ${examples.bashLayeredWithUser.imageName} ${pkgs.bash}/bin/bash -c 'test 555 == $(stat --format=%a /nix) && test 555 == $(stat --format=%a /nix/store)'",
"docker rmi ${examples.bashLayeredWithUser.imageName}",
)
with subtest("The nix binary symlinks are intact"):
docker.succeed(
"docker load --input='${examples.nix}'",
"docker run --rm ${examples.nix.imageName} ${pkgs.bash}/bin/bash -c 'test nix == $(readlink ${pkgs.nix}/bin/nix-daemon)'",
"docker rmi ${examples.nix.imageName}",
)
with subtest("The nix binary symlinks are intact when the image is layered"):
docker.succeed(
"docker load --input='${examples.nixLayered}'",
"docker run --rm ${examples.nixLayered.imageName} ${pkgs.bash}/bin/bash -c 'test nix == $(readlink ${pkgs.nix}/bin/nix-daemon)'",
"docker rmi ${examples.nixLayered.imageName}",
)
with subtest("The pullImage tool works"):
docker.succeed(
"docker load --input='${examples.nixFromDockerHub}'",
"docker run --rm nix:2.2.1 nix-store --version",
"docker rmi nix:2.2.1",
)
with subtest("runAsRoot and entry point work"):
docker.succeed(
"docker load --input='${examples.nginx}'",
"docker run --name nginx -d -p 8000:80 ${examples.nginx.imageName}",
)
docker.wait_until_succeeds("curl -f http://localhost:8000/")
docker.succeed(
"docker rm --force nginx",
"docker rmi '${examples.nginx.imageName}'",
)
with subtest("A pulled image can be used as base image"):
docker.succeed(
"docker load --input='${examples.onTopOfPulledImage}'",
"docker run --rm ontopofpulledimage hello",
"docker rmi ontopofpulledimage",
)
with subtest("Regression test for issue #34779"):
docker.succeed(
"docker load --input='${examples.runAsRootExtraCommands}'",
"docker run --rm runasrootextracommands cat extraCommands",
"docker run --rm runasrootextracommands cat runAsRoot",
"docker rmi '${examples.runAsRootExtraCommands.imageName}'",
)
with subtest("Ensure Docker images can use an unstable date"):
docker.succeed(
"docker load --input='${examples.unstableDate}'"
)
assert unix_time_second1 not in docker.succeed(
"docker inspect ${examples.unstableDate.imageName} "
+ "| ${pkgs.jq}/bin/jq -r .[].Created"
)
with subtest("Ensure Layered Docker images can use an unstable date"):
docker.succeed(
"docker load --input='${examples.unstableDateLayered}'"
)
assert unix_time_second1 not in docker.succeed(
"docker inspect ${examples.unstableDateLayered.imageName} "
+ "| ${pkgs.jq}/bin/jq -r .[].Created"
)
with subtest("Ensure Layered Docker images work"):
docker.succeed(
"docker load --input='${examples.layered-image}'",
"docker run --rm ${examples.layered-image.imageName}",
"docker run --rm ${examples.layered-image.imageName} cat extraCommands",
)
with subtest("Ensure images built on top of layered Docker images work"):
docker.succeed(
"docker load --input='${examples.layered-on-top}'",
"docker run --rm ${examples.layered-on-top.imageName}",
)
with subtest("Ensure layered images built on top of layered Docker images work"):
docker.succeed(
"docker load --input='${examples.layered-on-top-layered}'",
"docker run --rm ${examples.layered-on-top-layered.imageName}",
)
def set_of_layers(image_name):
return set(
docker.succeed(
f"docker inspect {image_name} "
+ "| ${pkgs.jq}/bin/jq -r '.[] | .RootFS.Layers | .[]'"
).split()
)
with subtest("Ensure layers are shared between images"):
docker.succeed(
"docker load --input='${examples.another-layered-image}'"
)
layers1 = set_of_layers("${examples.layered-image.imageName}")
layers2 = set_of_layers("${examples.another-layered-image.imageName}")
assert bool(layers1 & layers2)
with subtest("Ensure order of layers is correct"):
docker.succeed(
"docker load --input='${examples.layersOrder}'"
)
for index in 1, 2, 3:
assert f"layer{index}" in docker.succeed(
f"docker run --rm ${examples.layersOrder.imageName} cat /tmp/layer{index}"
)
with subtest("Ensure environment variables are correctly inherited"):
docker.succeed(
"docker load --input='${examples.environmentVariables}'"
)
out = docker.succeed("docker run --rm ${examples.environmentVariables.imageName} env")
env = out.splitlines()
assert "FROM_PARENT=true" in env, "envvars from the parent should be preserved"
assert "FROM_CHILD=true" in env, "envvars from the child should be preserved"
assert "LAST_LAYER=child" in env, "envvars from the child should take priority"
with subtest("Ensure environment variables of layered images are correctly inherited"):
docker.succeed(
"docker load --input='${examples.environmentVariablesLayered}'"
)
out = docker.succeed("docker run --rm ${examples.environmentVariablesLayered.imageName} env")
env = out.splitlines()
assert "FROM_PARENT=true" in env, "envvars from the parent should be preserved"
assert "FROM_CHILD=true" in env, "envvars from the child should be preserved"
assert "LAST_LAYER=child" in env, "envvars from the child should take priority"
with subtest(
"Ensure inherited environment variables of layered images are correctly resolved"
):
# Read environment variables as stored in image config
config = docker.succeed(
"tar -xOf ${examples.environmentVariablesLayered} manifest.json | ${pkgs.jq}/bin/jq -r .[].Config"
).strip()
out = docker.succeed(
f"tar -xOf ${examples.environmentVariablesLayered} {config} | ${pkgs.jq}/bin/jq -r '.config.Env | .[]'"
)
env = out.splitlines()
assert (
sum(entry.startswith("LAST_LAYER") for entry in env) == 1
), "envvars overridden by child should be unique"
with subtest("Ensure image with only 2 layers can be loaded"):
docker.succeed(
"docker load --input='${examples.two-layered-image}'"
)
with subtest(
"Ensure the bulk layer doesn't miss store paths (regression test for #78744)"
):
docker.succeed(
"docker load --input='${pkgs.dockerTools.examples.bulk-layer}'",
# Ensure the two output paths (ls and hello) are in the layer
"docker run bulk-layer ls /bin/hello",
)
with subtest(
"Ensure the bulk layer with a base image respects the number of maxLayers"
):
docker.succeed(
"docker load --input='${pkgs.dockerTools.examples.layered-bulk-layer}'",
# Ensure the image runs correctly
"docker run layered-bulk-layer ls /bin/hello",
)
# Ensure the image has the correct number of layers
assert len(set_of_layers("layered-bulk-layer")) == 4
with subtest("Ensure correct behavior when no store is needed"):
# This check tests that buildLayeredImage can build images that don't need a store.
docker.succeed(
"docker load --input='${pkgs.dockerTools.examples.no-store-paths}'"
)
# This check may be loosened to allow an *empty* store rather than *no* store.
docker.succeed("docker run --rm no-store-paths ls /")
docker.fail("docker run --rm no-store-paths ls /nix/store")
with subtest("Ensure buildLayeredImage does not change store path contents."):
docker.succeed(
"docker load --input='${pkgs.dockerTools.examples.filesInStore}'",
"docker run --rm file-in-store nix-store --verify --check-contents",
"docker run --rm file-in-store |& grep 'some data'",
)
with subtest("Ensure cross compiled image can be loaded and has correct arch."):
docker.succeed(
"docker load --input='${pkgs.dockerTools.examples.cross}'",
)
assert (
docker.succeed(
"docker inspect ${pkgs.dockerTools.examples.cross.imageName} "
+ "| ${pkgs.jq}/bin/jq -r .[].Architecture"
).strip()
== "${if pkgs.system == "aarch64-linux" then "amd64" else "arm64"}"
)
with subtest("buildLayeredImage doesn't dereference /nix/store symlink layers"):
docker.succeed(
"docker load --input='${examples.layeredStoreSymlink}'",
"docker run --rm ${examples.layeredStoreSymlink.imageName} bash -c 'test -L ${examples.layeredStoreSymlink.passthru.symlink}'",
"docker rmi ${examples.layeredStoreSymlink.imageName}",
)
with subtest("buildImage supports registry/ prefix in image name"):
docker.succeed(
"docker load --input='${examples.prefixedImage}'"
)
docker.succeed(
"docker images --format '{{.Repository}}' | grep -F '${examples.prefixedImage.imageName}'"
)
with subtest("buildLayeredImage supports registry/ prefix in image name"):
docker.succeed(
"docker load --input='${examples.prefixedLayeredImage}'"
)
docker.succeed(
"docker images --format '{{.Repository}}' | grep -F '${examples.prefixedLayeredImage.imageName}'"
)
'';
})