depot/pkgs/applications/networking/cluster/k3s/builder.nix
Luke Granger-Brown 57725ef3ec Squashed 'third_party/nixpkgs/' content from commit 76612b17c0ce
git-subtree-dir: third_party/nixpkgs
git-subtree-split: 76612b17c0ce71689921ca12d9ffdc9c23ce40b2
2024-11-10 23:59:47 +00:00

479 lines
16 KiB
Nix

lib:
{
# git tag
k3sVersion,
# commit hash
k3sCommit,
k3sRepoSha256 ? lib.fakeHash,
k3sVendorHash ? lib.fakeHash,
# taken from ./scripts/version.sh VERSION_ROOT https://github.com/k3s-io/k3s/blob/v1.23.3%2Bk3s1/scripts/version.sh#L47
k3sRootVersion,
k3sRootSha256 ? lib.fakeHash,
# Based on the traefik charts here: https://github.com/k3s-io/k3s/blob/d71ab6317e22dd34673faa307a412a37a16767f6/scripts/download#L29-L32
# see also https://github.com/k3s-io/k3s/blob/d71ab6317e22dd34673faa307a412a37a16767f6/manifests/traefik.yaml#L8
chartVersions,
# Air gap container images that are released as assets with every k3s release
imagesVersions,
# taken from ./scripts/version.sh VERSION_CNIPLUGINS https://github.com/k3s-io/k3s/blob/v1.23.3%2Bk3s1/scripts/version.sh#L45
k3sCNIVersion,
k3sCNISha256 ? lib.fakeHash,
# taken from ./scripts/version.sh VERSION_CONTAINERD
containerdVersion,
containerdSha256 ? lib.fakeHash,
# run `grep github.com/kubernetes-sigs/cri-tools go.mod | head -n1 | awk '{print $4}'` in the k3s repo at the tag
criCtlVersion,
updateScript ? null,
}@attrs:
# builder.nix contains a "builder" expression that, given k3s version and hash
# variables, creates a package for that version.
# Due to variance in k3s's build process, this builder only works for k3s 1.26+
# currently.
# It is likely we will have to split out additional builders for additional
# versions in the future, or customize this one further.
{
bash,
bridge-utils,
btrfs-progs,
buildGoModule,
conntrack-tools,
coreutils,
ethtool,
fetchFromGitHub,
fetchgit,
fetchurl,
fetchzip,
findutils,
gnugrep,
gnused,
go,
iproute2,
ipset,
iptables,
kmod,
lib,
libseccomp,
makeWrapper,
nixosTests,
pkg-config,
pkgsBuildBuild,
procps,
rsync,
runc,
runCommand,
socat,
sqlite,
stdenv,
systemd,
util-linux,
yq-go,
zstd,
}:
# k3s is a kinda weird derivation. One of the main points of k3s is the
# simplicity of it being one binary that can perform several tasks.
# However, when you have a good package manager (like nix), that doesn't
# actually make much of a difference; you don't really care if it's one binary
# or 10 since with a good package manager, installing and running it is
# identical.
# Since upstream k3s packages itself as one large binary with several
# "personalities" (in the form of subcommands like 'k3s agent' and 'k3s
# kubectl'), it ends up being easiest to mostly mimic upstream packaging, with
# some exceptions.
# K3s also carries patches to some packages (such as containerd and cni
# plugins), so we intentionally use the k3s versions of those binaries for k3s,
# even if the upstream version of those binaries exist in nixpkgs already. In
# the end, that means we have a thick k3s binary that behaves like the upstream
# one for the most part.
# However, k3s also bundles several pieces of unpatched software, from the
# strongswan vpn software, to iptables, to socat, conntrack, busybox, etc.
# Those pieces of software we entirely ignore upstream's handling of, and just
# make sure they're in the path if desired.
let
baseMeta = {
description = "Lightweight Kubernetes distribution";
license = lib.licenses.asl20;
homepage = "https://k3s.io";
maintainers = lib.teams.k3s.members;
platforms = lib.platforms.linux;
# resolves collisions with other installations of kubectl, crictl, ctr
# prefer non-k3s versions
priority = 5;
};
# https://github.com/k3s-io/k3s/blob/5fb370e53e0014dc96183b8ecb2c25a61e891e76/scripts/build#L19-L40
versionldflags = [
"-X github.com/k3s-io/k3s/pkg/version.Version=v${k3sVersion}"
"-X github.com/k3s-io/k3s/pkg/version.GitCommit=${lib.substring 0 8 k3sCommit}"
"-X github.com/k3s-io/k3s/pkg/version.UpstreamGolang=go${go.version}"
"-X k8s.io/client-go/pkg/version.gitVersion=v${k3sVersion}"
"-X k8s.io/client-go/pkg/version.gitCommit=${k3sCommit}"
"-X k8s.io/client-go/pkg/version.gitTreeState=clean"
"-X k8s.io/client-go/pkg/version.buildDate=1970-01-01T01:01:01Z"
"-X k8s.io/component-base/version.gitVersion=v${k3sVersion}"
"-X k8s.io/component-base/version.gitCommit=${k3sCommit}"
"-X k8s.io/component-base/version.gitTreeState=clean"
"-X k8s.io/component-base/version.buildDate=1970-01-01T01:01:01Z"
"-X github.com/kubernetes-sigs/cri-tools/pkg/version.Version=v${criCtlVersion}"
"-X github.com/containerd/containerd/version.Version=v${containerdVersion}"
"-X github.com/containerd/containerd/version.Package=github.com/k3s-io/containerd"
];
# bundled into the k3s binary
traefikChart = fetchurl chartVersions.traefik;
traefik-crdChart = fetchurl chartVersions.traefik-crd;
mutFirstChar =
f: s:
let
firstChar = f (lib.substring 0 1 s);
rest = lib.substring 1 (-1) s;
in
firstChar + rest;
kebabToCamel =
s:
mutFirstChar lib.toLower (lib.concatMapStrings (mutFirstChar lib.toUpper) (lib.splitString "-" s));
# finds the images archive for the desired architecture, aborts in case no suitable archive is found
findImagesArchive =
arch:
let
imagesVersionsNames = builtins.attrNames imagesVersions;
in
lib.findFirst (
n: lib.hasInfix arch n
) (abort "k3s: no airgap images for ${arch} available") imagesVersionsNames;
# a shortcut that provides the images archive for the host platform. Currently only supports
# aarch64 (arm64) and x86_64 (amd64), aborts on other architectures.
airgapImages = fetchurl (
if stdenv.hostPlatform.isAarch64 then
imagesVersions.${findImagesArchive "arm64"}
else if stdenv.hostPlatform.isx86_64 then
imagesVersions.${findImagesArchive "amd64"}
else
abort "k3s: airgap images cannot be found automatically for architecture ${stdenv.hostPlatform.linuxArch}, consider using an image archive with an explicit architecture."
);
# so, k3s is a complicated thing to package
# This derivation attempts to avoid including any random binaries from the
# internet. k3s-root is _mostly_ binaries built to be bundled in k3s (which
# we don't care about doing, we can add those as build or runtime
# dependencies using a real package manager).
# In addition to those binaries, it's also configuration though (right now
# mostly strongswan configuration), and k3s does use those files.
# As such, we download it in order to grab 'etc' and bundle it into the final
# k3s binary.
k3sRoot = fetchzip {
# Note: marked as apache 2.0 license
url = "https://github.com/k3s-io/k3s-root/releases/download/v${k3sRootVersion}/k3s-root-amd64.tar";
sha256 = k3sRootSha256;
stripRoot = false;
};
k3sCNIPlugins = buildGoModule rec {
pname = "k3s-cni-plugins";
version = k3sCNIVersion;
vendorHash = null;
subPackages = [ "." ];
src = fetchFromGitHub {
owner = "rancher";
repo = "plugins";
rev = "v${version}";
sha256 = k3sCNISha256;
};
postInstall = ''
mv $out/bin/plugins $out/bin/cni
'';
meta = baseMeta // {
description = "CNI plugins, as patched by rancher for k3s";
};
};
# Grab this separately from a build because it's used by both stages of the
# k3s build.
k3sRepo = fetchgit {
url = "https://github.com/k3s-io/k3s";
rev = "v${k3sVersion}";
sha256 = k3sRepoSha256;
};
# Modify the k3s installer script so that we can let it install only
# killall.sh
k3sKillallSh = runCommand "k3s-killall.sh" { } ''
# Copy the upstream k3s install script except for the last lines that
# actually run the install process
sed --quiet '/# --- run the install process --/q;p' ${k3sRepo}/install.sh > install.sh
# Let killall expect "containerd-shim" in the Nix store
to_replace="/data/\[\^/\]\*/bin/containerd-shim"
replacement="/nix/store/.*k3s-containerd.*/bin/containerd-shim"
changes=$(sed -i "s|$to_replace|$replacement| w /dev/stdout" install.sh)
if [ -z "$changes" ]; then
echo "failed to replace \"$to_replace\" in k3s installer script (install.sh)"
exit 1
fi
remove_matching_line() {
line_to_delete=$(grep -n "$1" install.sh | cut -d : -f 1 || true)
if [ -z $line_to_delete ]; then
echo "failed to find expression \"$1\" in k3s installer script (install.sh)"
exit 1
fi
sed -i "''${line_to_delete}d" install.sh
}
# Don't change mode and owner of killall
remove_matching_line "chmod.*KILLALL_K3S_SH"
remove_matching_line "chown.*KILLALL_K3S_SH"
# Execute only the "create_killall" function of the installer script
sed -i '$acreate_killall' install.sh
KILLALL_K3S_SH=$out bash install.sh
'';
# Stage 1 of the k3s build:
# Let's talk about how k3s is structured.
# One of the ideas of k3s is that there's the single "k3s" binary which can
# do everything you need, from running a k3s server, to being a worker node,
# to running kubectl.
# The way that actually works is that k3s is a single go binary that contains
# a bunch of bindata that it unpacks at runtime into directories (either the
# user's home directory or /var/lib/rancher if run as root).
# This bindata includes both binaries and configuration.
# In order to let nixpkgs do all its autostripping/patching/etc, we split this into two derivations.
# First, we build all the binaries that get packed into the thick k3s binary
# (and output them from one derivation so they'll all be suitably patched up).
# Then, we bundle those binaries into our thick k3s binary and use that as
# the final single output.
# This approach was chosen because it ensures the bundled binaries all are
# correctly built to run with nix (we can lean on the existing buildGoModule
# stuff), and we can again lean on that tooling for the final k3s binary too.
# Other alternatives would be to manually run the
# strip/patchelf/remove-references step ourselves in the installPhase of the
# derivation when we've built all the binaries, but haven't bundled them in
# with generated bindata yet.
k3sServer = buildGoModule {
pname = "k3s-server";
version = k3sVersion;
src = k3sRepo;
vendorHash = k3sVendorHash;
nativeBuildInputs = [ pkg-config ];
buildInputs = [
libseccomp
sqlite.dev
];
subPackages = [ "cmd/server" ];
ldflags = versionldflags;
tags = [
"ctrd"
"libsqlite3"
"linux"
];
# create the multicall symlinks for k3s
postInstall = ''
mv $out/bin/server $out/bin/k3s
pushd $out
# taken verbatim from https://github.com/k3s-io/k3s/blob/v1.23.3%2Bk3s1/scripts/build#L105-L113
ln -s k3s ./bin/containerd
ln -s k3s ./bin/crictl
ln -s k3s ./bin/ctr
ln -s k3s ./bin/k3s-agent
ln -s k3s ./bin/k3s-certificate
ln -s k3s ./bin/k3s-completion
ln -s k3s ./bin/k3s-etcd-snapshot
ln -s k3s ./bin/k3s-secrets-encrypt
ln -s k3s ./bin/k3s-server
ln -s k3s ./bin/k3s-token
ln -s k3s ./bin/kubectl
popd
'';
meta = baseMeta // {
description = "Various binaries that get packaged into the final k3s binary";
};
};
# Only used for the shim since
# https://github.com/k3s-io/k3s/blob/v1.27.2%2Bk3s1/scripts/build#L153
k3sContainerd = buildGoModule {
pname = "k3s-containerd";
version = containerdVersion;
src = fetchFromGitHub {
owner = "k3s-io";
repo = "containerd";
rev = "v${containerdVersion}";
sha256 = containerdSha256;
};
vendorHash = null;
buildInputs = [ btrfs-progs ];
subPackages = [ "cmd/containerd-shim-runc-v2" ];
ldflags = versionldflags;
};
in
buildGoModule rec {
pname = "k3s";
version = k3sVersion;
pos = builtins.unsafeGetAttrPos "k3sVersion" attrs;
tags = [
"libsqlite3"
"linux"
"ctrd"
];
src = k3sRepo;
vendorHash = k3sVendorHash;
postPatch = ''
# Nix prefers dynamically linked binaries over static binary.
substituteInPlace scripts/package-cli \
--replace '"$LDFLAGS $STATIC" -o' \
'"$LDFLAGS" -o' \
--replace "STATIC=\"-extldflags \'-static\'\"" \
""
# Upstream codegen fails with trimpath set. Removes "trimpath" for 'go generate':
substituteInPlace scripts/package-cli \
--replace '"''${GO}" generate' \
'GOFLAGS="" \
GOOS="${pkgsBuildBuild.go.GOOS}" \
GOARCH="${pkgsBuildBuild.go.GOARCH}" \
CC="${pkgsBuildBuild.stdenv.cc}/bin/cc" \
"''${GO}" generate'
'';
# Important utilities used by the kubelet, see
# https://github.com/kubernetes/kubernetes/issues/26093#issuecomment-237202494
# Note the list in that issue is stale and some aren't relevant for k3s.
k3sRuntimeDeps = [
kmod
socat
iptables
iproute2
ipset
bridge-utils
ethtool
util-linux # kubelet wants 'nsenter' from util-linux: https://github.com/kubernetes/kubernetes/issues/26093#issuecomment-705994388
conntrack-tools
runc
bash
];
k3sKillallDeps = [
bash
systemd
procps
coreutils
gnugrep
findutils
gnused
];
buildInputs = k3sRuntimeDeps;
nativeBuildInputs = [
makeWrapper
rsync
yq-go
zstd
];
# embedded in the final k3s cli
propagatedBuildInputs = [
k3sCNIPlugins
k3sContainerd
k3sServer
];
# We override most of buildPhase due to peculiarities in k3s's build.
# Specifically, it has a 'go generate' which runs part of the package. See
# this comment:
# https://github.com/NixOS/nixpkgs/pull/158089#discussion_r799965694
# So, why do we use buildGoModule at all? For the `vendorHash` / `go mod download` stuff primarily.
buildPhase = ''
runHook preBuild
patchShebangs ./scripts/package-cli ./scripts/download ./scripts/build-upload
# copy needed 'go generate' inputs into place
mkdir -p ./bin/aux
rsync -a --no-perms ${k3sServer}/bin/ ./bin/
ln -vsf ${k3sCNIPlugins}/bin/cni ./bin/cni
ln -vsf ${k3sContainerd}/bin/containerd-shim-runc-v2 ./bin
rsync -a --no-perms --chmod u=rwX ${k3sRoot}/etc/ ./etc/
mkdir -p ./build/static/charts
cp ${traefikChart} ./build/static/charts
cp ${traefik-crdChart} ./build/static/charts
export ARCH=$GOARCH
export DRONE_TAG="v${k3sVersion}"
export DRONE_COMMIT="${k3sCommit}"
# use ./scripts/package-cli to run 'go generate' + 'go build'
./scripts/package-cli
mkdir -p $out/bin
runHook postBuild
'';
# Otherwise it depends on 'getGoDirs', which is normally set in buildPhase
doCheck = false;
installPhase = ''
runHook preInstall
# wildcard to match the arm64 build too
install -m 0755 dist/artifacts/k3s* -D $out/bin/k3s
wrapProgram $out/bin/k3s \
--prefix PATH : ${lib.makeBinPath k3sRuntimeDeps} \
--prefix PATH : "$out/bin"
ln -s $out/bin/k3s $out/bin/kubectl
ln -s $out/bin/k3s $out/bin/crictl
ln -s $out/bin/k3s $out/bin/ctr
install -m 0755 ${k3sKillallSh} -D $out/bin/k3s-killall.sh
wrapProgram $out/bin/k3s-killall.sh \
--prefix PATH : ${lib.makeBinPath (k3sRuntimeDeps ++ k3sKillallDeps)}
runHook postInstall
'';
doInstallCheck = true;
installCheckPhase = ''
runHook preInstallCheck
$out/bin/k3s --version | grep -F "v${k3sVersion}" >/dev/null
runHook postInstallCheck
'';
passthru =
{
inherit airgapImages;
k3sCNIPlugins = k3sCNIPlugins;
k3sContainerd = k3sContainerd;
k3sRepo = k3sRepo;
k3sRoot = k3sRoot;
k3sServer = k3sServer;
mkTests =
version:
let
k3s_version = "k3s_" + lib.replaceStrings [ "." ] [ "_" ] (lib.versions.majorMinor version);
in
lib.mapAttrs (name: value: nixosTests.k3s.${name}.${k3s_version}) nixosTests.k3s;
tests = passthru.mkTests k3sVersion;
updateScript = updateScript;
}
// (lib.mapAttrs' (
name: _: lib.nameValuePair (kebabToCamel name) (fetchurl imagesVersions.${name})
) imagesVersions);
meta = baseMeta;
}