1299 lines
47 KiB
Nix
1299 lines
47 KiB
Nix
{ bashInteractive
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, buildPackages
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, cacert
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, callPackage
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, closureInfo
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, coreutils
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, e2fsprogs
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, proot
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, fakeNss
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, fakeroot
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, file
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, go
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, jq
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, jshon
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, lib
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, makeWrapper
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, moreutils
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, nix
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, nixosTests
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, pigz
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, rsync
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, runCommand
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, runtimeShell
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, shadow
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, skopeo
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, storeDir ? builtins.storeDir
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, substituteAll
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, symlinkJoin
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, tarsum
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, util-linux
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, vmTools
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, writeClosure
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, writeScript
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, writeShellScriptBin
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, writeText
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, writeTextDir
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, writePython3
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, zstd
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}:
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let
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inherit (lib)
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optionals
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optionalString
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;
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inherit (lib)
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escapeShellArgs
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toList
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;
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mkDbExtraCommand = contents:
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let
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contentsList = if builtins.isList contents then contents else [ contents ];
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in
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''
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echo "Generating the nix database..."
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echo "Warning: only the database of the deepest Nix layer is loaded."
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echo " If you want to use nix commands in the container, it would"
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echo " be better to only have one layer that contains a nix store."
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export NIX_REMOTE=local?root=$PWD
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# A user is required by nix
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# https://github.com/NixOS/nix/blob/9348f9291e5d9e4ba3c4347ea1b235640f54fd79/src/libutil/util.cc#L478
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export USER=nobody
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${buildPackages.nix}/bin/nix-store --load-db < ${closureInfo {rootPaths = contentsList;}}/registration
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# Reset registration times to make the image reproducible
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${buildPackages.sqlite}/bin/sqlite3 nix/var/nix/db/db.sqlite "UPDATE ValidPaths SET registrationTime = ''${SOURCE_DATE_EPOCH}"
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mkdir -p nix/var/nix/gcroots/docker/
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for i in ${lib.concatStringsSep " " contentsList}; do
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ln -s $i nix/var/nix/gcroots/docker/$(basename $i)
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done;
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'';
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# The OCI Image specification recommends that configurations use values listed
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# in the Go Language document for GOARCH.
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# Reference: https://github.com/opencontainers/image-spec/blob/master/config.md#properties
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# For the mapping from Nixpkgs system parameters to GOARCH, we can reuse the
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# mapping from the go package.
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defaultArchitecture = go.GOARCH;
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compressors = {
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none = {
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ext = "";
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nativeInputs = [ ];
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compress = "cat";
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decompress = "cat";
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};
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gz = {
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ext = ".gz";
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nativeInputs = [ pigz ];
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compress = "pigz -p$NIX_BUILD_CORES -nTR";
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decompress = "pigz -d -p$NIX_BUILD_CORES";
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};
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zstd = {
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ext = ".zst";
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nativeInputs = [ zstd ];
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compress = "zstd -T$NIX_BUILD_CORES";
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decompress = "zstd -d -T$NIX_BUILD_CORES";
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};
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};
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compressorForImage = compressor: imageName: compressors.${compressor} or
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(throw "in docker image ${imageName}: compressor must be one of: [${toString builtins.attrNames compressors}]");
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in
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rec {
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examples = callPackage ./examples.nix {
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inherit buildImage buildLayeredImage fakeNss pullImage shadowSetup buildImageWithNixDb streamNixShellImage;
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};
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tests = {
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inherit (nixosTests)
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docker-tools
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docker-tools-overlay
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# requires remote builder
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# docker-tools-cross
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;
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};
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pullImage =
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let
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fixName = name: builtins.replaceStrings [ "/" ":" ] [ "-" "-" ] name;
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in
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{ imageName
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# To find the digest of an image, you can use skopeo:
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# see doc/functions.xml
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, imageDigest
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, sha256
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, os ? "linux"
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, # Image architecture, defaults to the architecture of the `hostPlatform` when unset
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arch ? defaultArchitecture
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# This is used to set name to the pulled image
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, finalImageName ? imageName
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# This used to set a tag to the pulled image
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, finalImageTag ? "latest"
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# This is used to disable TLS certificate verification, allowing access to http registries on (hopefully) trusted networks
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, tlsVerify ? true
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, name ? fixName "docker-image-${finalImageName}-${finalImageTag}.tar"
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}:
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runCommand name
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{
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inherit imageDigest;
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imageName = finalImageName;
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imageTag = finalImageTag;
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impureEnvVars = lib.fetchers.proxyImpureEnvVars;
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outputHashMode = "flat";
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outputHashAlgo = "sha256";
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outputHash = sha256;
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nativeBuildInputs = [ skopeo ];
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SSL_CERT_FILE = "${cacert.out}/etc/ssl/certs/ca-bundle.crt";
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sourceURL = "docker://${imageName}@${imageDigest}";
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destNameTag = "${finalImageName}:${finalImageTag}";
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} ''
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skopeo \
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--insecure-policy \
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--tmpdir=$TMPDIR \
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--override-os ${os} \
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--override-arch ${arch} \
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copy \
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--src-tls-verify=${lib.boolToString tlsVerify} \
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"$sourceURL" "docker-archive://$out:$destNameTag" \
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| cat # pipe through cat to force-disable progress bar
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'';
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# We need to sum layer.tar, not a directory, hence tarsum instead of nix-hash.
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# And we cannot untar it, because then we cannot preserve permissions etc.
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inherit tarsum; # pkgs.dockerTools.tarsum
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# buildEnv creates symlinks to dirs, which is hard to edit inside the overlay VM
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mergeDrvs =
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{ derivations
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, onlyDeps ? false
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}:
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runCommand "merge-drvs"
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{
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inherit derivations onlyDeps;
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} ''
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if [[ -n "$onlyDeps" ]]; then
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echo $derivations > $out
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exit 0
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fi
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mkdir $out
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for derivation in $derivations; do
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echo "Merging $derivation..."
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if [[ -d "$derivation" ]]; then
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# If it's a directory, copy all of its contents into $out.
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cp -drf --preserve=mode -f $derivation/* $out/
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else
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# Otherwise treat the derivation as a tarball and extract it
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# into $out.
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tar -C $out -xpf $drv || true
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fi
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done
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'';
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# Helper for setting up the base files for managing users and
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# groups, only if such files don't exist already. It is suitable for
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# being used in a runAsRoot script.
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shadowSetup = ''
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export PATH=${shadow}/bin:$PATH
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mkdir -p /etc/pam.d
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if [[ ! -f /etc/passwd ]]; then
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echo "root:x:0:0::/root:${runtimeShell}" > /etc/passwd
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echo "root:!x:::::::" > /etc/shadow
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fi
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if [[ ! -f /etc/group ]]; then
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echo "root:x:0:" > /etc/group
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echo "root:x::" > /etc/gshadow
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fi
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if [[ ! -f /etc/pam.d/other ]]; then
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cat > /etc/pam.d/other <<EOF
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account sufficient pam_unix.so
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auth sufficient pam_rootok.so
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password requisite pam_unix.so nullok yescrypt
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session required pam_unix.so
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EOF
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fi
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if [[ ! -f /etc/login.defs ]]; then
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touch /etc/login.defs
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fi
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'';
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# Run commands in a virtual machine.
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runWithOverlay =
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{ name
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, fromImage ? null
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, fromImageName ? null
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, fromImageTag ? null
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, diskSize ? 1024
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, buildVMMemorySize ? 512
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, preMount ? ""
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, postMount ? ""
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, postUmount ? ""
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}:
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vmTools.runInLinuxVM (
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runCommand name
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{
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preVM = vmTools.createEmptyImage {
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size = diskSize;
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fullName = "docker-run-disk";
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destination = "./image";
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};
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inherit fromImage fromImageName fromImageTag;
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memSize = buildVMMemorySize;
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nativeBuildInputs = [ util-linux e2fsprogs jshon rsync jq ];
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} ''
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mkdir disk
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mkfs /dev/${vmTools.hd}
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mount /dev/${vmTools.hd} disk
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cd disk
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function dedup() {
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declare -A seen
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while read ln; do
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if [[ -z "''${seen["$ln"]:-}" ]]; then
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echo "$ln"; seen["$ln"]=1
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fi
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done
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}
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if [[ -n "$fromImage" ]]; then
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echo "Unpacking base image..."
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mkdir image
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tar -C image -xpf "$fromImage"
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if [[ -n "$fromImageName" ]] && [[ -n "$fromImageTag" ]]; then
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parentID="$(
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cat "image/manifest.json" |
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jq -r '.[] | select(.RepoTags | contains([$desiredTag])) | rtrimstr(".json")' \
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--arg desiredTag "$fromImageName:$fromImageTag"
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)"
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else
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echo "From-image name or tag wasn't set. Reading the first ID."
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parentID="$(cat "image/manifest.json" | jq -r '.[0].Config | rtrimstr(".json")')"
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fi
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# In case of repeated layers, unpack only the last occurrence of each
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cat ./image/manifest.json | jq -r '.[0].Layers | .[]' | tac | dedup | tac > layer-list
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else
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touch layer-list
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fi
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# Unpack all of the parent layers into the image.
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lowerdir=""
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extractionID=0
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for layerTar in $(cat layer-list); do
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echo "Unpacking layer $layerTar"
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extractionID=$((extractionID + 1))
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mkdir -p image/$extractionID/layer
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tar -C image/$extractionID/layer -xpf image/$layerTar
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rm image/$layerTar
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find image/$extractionID/layer -name ".wh.*" -exec bash -c 'name="$(basename {}|sed "s/^.wh.//")"; mknod "$(dirname {})/$name" c 0 0; rm {}' \;
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# Get the next lower directory and continue the loop.
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lowerdir=image/$extractionID/layer''${lowerdir:+:}$lowerdir
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done
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mkdir work
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mkdir layer
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mkdir mnt
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${lib.optionalString (preMount != "") ''
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# Execute pre-mount steps
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echo "Executing pre-mount steps..."
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${preMount}
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''}
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if [ -n "$lowerdir" ]; then
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mount -t overlay overlay -olowerdir=$lowerdir,workdir=work,upperdir=layer mnt
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else
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mount --bind layer mnt
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fi
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${lib.optionalString (postMount != "") ''
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# Execute post-mount steps
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echo "Executing post-mount steps..."
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${postMount}
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''}
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umount mnt
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(
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cd layer
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cmd='name="$(basename {})"; touch "$(dirname {})/.wh.$name"; rm "{}"'
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find . -type c -exec bash -c "$cmd" \;
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)
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${postUmount}
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'');
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exportImage = { name ? fromImage.name, fromImage, fromImageName ? null, fromImageTag ? null, diskSize ? 1024 }:
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runWithOverlay {
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inherit name fromImage fromImageName fromImageTag diskSize;
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postMount = ''
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echo "Packing raw image..."
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tar -C mnt --hard-dereference --sort=name --mtime="@$SOURCE_DATE_EPOCH" -cf $out/layer.tar .
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'';
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postUmount = ''
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mv $out/layer.tar .
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rm -rf $out
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mv layer.tar $out
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'';
|
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};
|
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|
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# Create an executable shell script which has the coreutils in its
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# PATH. Since root scripts are executed in a blank environment, even
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# things like `ls` or `echo` will be missing.
|
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shellScript = name: text:
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writeScript name ''
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#!${runtimeShell}
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set -e
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export PATH=${coreutils}/bin:/bin
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${text}
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'';
|
|
|
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# Create a "layer" (set of files).
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mkPureLayer =
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{
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# Name of the layer
|
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name
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, # JSON containing configuration and metadata for this layer.
|
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baseJson
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, # Files to add to the layer.
|
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copyToRoot ? null
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, # When copying the contents into the image, preserve symlinks to
|
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# directories (see `rsync -K`). Otherwise, transform those symlinks
|
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# into directories.
|
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keepContentsDirlinks ? false
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, # Additional commands to run on the layer before it is tar'd up.
|
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extraCommands ? ""
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, uid ? 0
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, gid ? 0
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}:
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runCommand "docker-layer-${name}"
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{
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inherit baseJson extraCommands;
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contents = copyToRoot;
|
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nativeBuildInputs = [ jshon rsync tarsum ];
|
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}
|
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''
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mkdir layer
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if [[ -n "$contents" ]]; then
|
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echo "Adding contents..."
|
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for item in $contents; do
|
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echo "Adding $item"
|
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rsync -a${if keepContentsDirlinks then "K" else "k"} --chown=0:0 $item/ layer/
|
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done
|
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else
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echo "No contents to add to layer."
|
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fi
|
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|
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chmod ug+w layer
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|
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if [[ -n "$extraCommands" ]]; then
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(cd layer; eval "$extraCommands")
|
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fi
|
|
|
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# Tar up the layer and throw it into 'layer.tar'.
|
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echo "Packing layer..."
|
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mkdir $out
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tarhash=$(tar -C layer --hard-dereference --sort=name --mtime="@$SOURCE_DATE_EPOCH" --owner=${toString uid} --group=${toString gid} -cf - . | tee -p $out/layer.tar | tarsum)
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|
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# Add a 'checksum' field to the JSON, with the value set to the
|
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# checksum of the tarball.
|
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cat ${baseJson} | jshon -s "$tarhash" -i checksum > $out/json
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|
|
|
# Indicate to docker that we're using schema version 1.0.
|
|
echo -n "1.0" > $out/VERSION
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|
|
|
echo "Finished building layer '${name}'"
|
|
'';
|
|
|
|
# Make a "root" layer; required if we need to execute commands as a
|
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# privileged user on the image. The commands themselves will be
|
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# performed in a virtual machine sandbox.
|
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mkRootLayer =
|
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{
|
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# Name of the image.
|
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name
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, # Script to run as root. Bash.
|
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runAsRoot
|
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, # Files to add to the layer. If null, an empty layer will be created.
|
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# To add packages to /bin, use `buildEnv` or similar.
|
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copyToRoot ? null
|
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, # When copying the contents into the image, preserve symlinks to
|
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# directories (see `rsync -K`). Otherwise, transform those symlinks
|
|
# into directories.
|
|
keepContentsDirlinks ? false
|
|
, # JSON containing configuration and metadata for this layer.
|
|
baseJson
|
|
, # Existing image onto which to append the new layer.
|
|
fromImage ? null
|
|
, # Name of the image we're appending onto.
|
|
fromImageName ? null
|
|
, # Tag of the image we're appending onto.
|
|
fromImageTag ? null
|
|
, # How much disk to allocate for the temporary virtual machine.
|
|
diskSize ? 1024
|
|
, # How much memory to allocate for the temporary virtual machine.
|
|
buildVMMemorySize ? 512
|
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, # Commands (bash) to run on the layer; these do not require sudo.
|
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extraCommands ? ""
|
|
}:
|
|
# Generate an executable script from the `runAsRoot` text.
|
|
let
|
|
runAsRootScript = shellScript "run-as-root.sh" runAsRoot;
|
|
extraCommandsScript = shellScript "extra-commands.sh" extraCommands;
|
|
in
|
|
runWithOverlay {
|
|
name = "docker-layer-${name}";
|
|
|
|
inherit fromImage fromImageName fromImageTag diskSize buildVMMemorySize;
|
|
|
|
preMount = lib.optionalString (copyToRoot != null && copyToRoot != [ ]) ''
|
|
echo "Adding contents..."
|
|
for item in ${escapeShellArgs (map (c: "${c}") (toList copyToRoot))}; do
|
|
echo "Adding $item..."
|
|
rsync -a${if keepContentsDirlinks then "K" else "k"} --chown=0:0 $item/ layer/
|
|
done
|
|
|
|
chmod ug+w layer
|
|
'';
|
|
|
|
postMount = ''
|
|
mkdir -p mnt/{dev,proc,sys,tmp} mnt${storeDir}
|
|
|
|
# Mount /dev, /sys and the nix store as shared folders.
|
|
mount --rbind /dev mnt/dev
|
|
mount --rbind /sys mnt/sys
|
|
mount --rbind ${storeDir} mnt${storeDir}
|
|
|
|
# Execute the run as root script. See 'man unshare' for
|
|
# details on what's going on here; basically this command
|
|
# means that the runAsRootScript will be executed in a nearly
|
|
# completely isolated environment.
|
|
#
|
|
# Ideally we would use --mount-proc=mnt/proc or similar, but this
|
|
# doesn't work. The workaround is to setup proc after unshare.
|
|
# See: https://github.com/karelzak/util-linux/issues/648
|
|
unshare -imnpuf --mount-proc sh -c 'mount --rbind /proc mnt/proc && chroot mnt ${runAsRootScript}'
|
|
|
|
# Unmount directories and remove them.
|
|
umount -R mnt/dev mnt/sys mnt${storeDir}
|
|
rmdir --ignore-fail-on-non-empty \
|
|
mnt/dev mnt/proc mnt/sys mnt${storeDir} \
|
|
mnt$(dirname ${storeDir})
|
|
'';
|
|
|
|
postUmount = ''
|
|
(cd layer; ${extraCommandsScript})
|
|
|
|
echo "Packing layer..."
|
|
mkdir -p $out
|
|
tarhash=$(tar -C layer --hard-dereference --sort=name --mtime="@$SOURCE_DATE_EPOCH" -cf - . |
|
|
tee -p $out/layer.tar |
|
|
${tarsum}/bin/tarsum)
|
|
|
|
cat ${baseJson} | jshon -s "$tarhash" -i checksum > $out/json
|
|
# Indicate to docker that we're using schema version 1.0.
|
|
echo -n "1.0" > $out/VERSION
|
|
|
|
echo "Finished building layer '${name}'"
|
|
'';
|
|
};
|
|
|
|
buildLayeredImage = lib.makeOverridable ({ name, compressor ? "gz", ... }@args:
|
|
let
|
|
stream = streamLayeredImage (builtins.removeAttrs args ["compressor"]);
|
|
compress = compressorForImage compressor name;
|
|
in
|
|
runCommand "${baseNameOf name}.tar${compress.ext}"
|
|
{
|
|
inherit (stream) imageName;
|
|
passthru = { inherit (stream) imageTag; inherit stream; };
|
|
nativeBuildInputs = compress.nativeInputs;
|
|
} "${stream} | ${compress.compress} > $out"
|
|
);
|
|
|
|
# 1. extract the base image
|
|
# 2. create the layer
|
|
# 3. add layer deps to the layer itself, diffing with the base image
|
|
# 4. compute the layer id
|
|
# 5. put the layer in the image
|
|
# 6. repack the image
|
|
buildImage = lib.makeOverridable (
|
|
args@{
|
|
# Image name.
|
|
name
|
|
, # Image tag, when null then the nix output hash will be used.
|
|
tag ? null
|
|
, # Parent image, to append to.
|
|
fromImage ? null
|
|
, # Name of the parent image; will be read from the image otherwise.
|
|
fromImageName ? null
|
|
, # Tag of the parent image; will be read from the image otherwise.
|
|
fromImageTag ? null
|
|
, # Files to put on the image (a nix store path or list of paths).
|
|
copyToRoot ? null
|
|
, # When copying the contents into the image, preserve symlinks to
|
|
# directories (see `rsync -K`). Otherwise, transform those symlinks
|
|
# into directories.
|
|
keepContentsDirlinks ? false
|
|
, # Docker config; e.g. what command to run on the container.
|
|
config ? null
|
|
, # Image architecture, defaults to the architecture of the `hostPlatform` when unset
|
|
architecture ? defaultArchitecture
|
|
, # Optional bash script to run on the files prior to fixturizing the layer.
|
|
extraCommands ? ""
|
|
, uid ? 0
|
|
, gid ? 0
|
|
, # Optional bash script to run as root on the image when provisioning.
|
|
runAsRoot ? null
|
|
, # Size of the virtual machine disk to provision when building the image.
|
|
diskSize ? 1024
|
|
, # Size of the virtual machine memory to provision when building the image.
|
|
buildVMMemorySize ? 512
|
|
, # Time of creation of the image.
|
|
created ? "1970-01-01T00:00:01Z"
|
|
, # Compressor to use. One of: none, gz, zstd.
|
|
compressor ? "gz"
|
|
, # Deprecated.
|
|
contents ? null
|
|
,
|
|
}:
|
|
|
|
let
|
|
checked =
|
|
lib.warnIf (contents != null)
|
|
"in docker image ${name}: The contents parameter is deprecated. Change to copyToRoot if the contents are designed to be copied to the root filesystem, such as when you use `buildEnv` or similar between contents and your packages. Use copyToRoot = buildEnv { ... }; or similar if you intend to add packages to /bin."
|
|
lib.throwIf (contents != null && copyToRoot != null) "in docker image ${name}: You can not specify both contents and copyToRoot."
|
|
;
|
|
|
|
rootContents = if copyToRoot == null then contents else copyToRoot;
|
|
|
|
baseName = baseNameOf name;
|
|
|
|
# Create a JSON blob of the configuration. Set the date to unix zero.
|
|
baseJson =
|
|
let
|
|
pure = writeText "${baseName}-config.json" (builtins.toJSON {
|
|
inherit created config architecture;
|
|
preferLocalBuild = true;
|
|
os = "linux";
|
|
});
|
|
impure = runCommand "${baseName}-config.json"
|
|
{
|
|
nativeBuildInputs = [ jq ];
|
|
preferLocalBuild = true;
|
|
}
|
|
''
|
|
jq ".created = \"$(TZ=utc date --iso-8601="seconds")\"" ${pure} > $out
|
|
'';
|
|
in
|
|
if created == "now" then impure else pure;
|
|
|
|
compress = compressorForImage compressor name;
|
|
|
|
layer =
|
|
if runAsRoot == null
|
|
then
|
|
mkPureLayer
|
|
{
|
|
name = baseName;
|
|
inherit baseJson keepContentsDirlinks extraCommands uid gid;
|
|
copyToRoot = rootContents;
|
|
} else
|
|
mkRootLayer {
|
|
name = baseName;
|
|
inherit baseJson fromImage fromImageName fromImageTag
|
|
keepContentsDirlinks runAsRoot diskSize buildVMMemorySize
|
|
extraCommands;
|
|
copyToRoot = rootContents;
|
|
};
|
|
result = runCommand "docker-image-${baseName}.tar${compress.ext}"
|
|
{
|
|
nativeBuildInputs = [ jshon jq moreutils ] ++ compress.nativeInputs;
|
|
# Image name must be lowercase
|
|
imageName = lib.toLower name;
|
|
imageTag = lib.optionalString (tag != null) tag;
|
|
inherit fromImage baseJson;
|
|
layerClosure = writeClosure [ layer ];
|
|
passthru.buildArgs = args;
|
|
passthru.layer = layer;
|
|
passthru.imageTag =
|
|
if tag != null
|
|
then tag
|
|
else
|
|
lib.head (lib.strings.splitString "-" (baseNameOf (builtins.unsafeDiscardStringContext result.outPath)));
|
|
} ''
|
|
${lib.optionalString (tag == null) ''
|
|
outName="$(basename "$out")"
|
|
outHash=$(echo "$outName" | cut -d - -f 1)
|
|
|
|
imageTag=$outHash
|
|
''}
|
|
|
|
# Print tar contents:
|
|
# 1: Interpreted as relative to the root directory
|
|
# 2: With no trailing slashes on directories
|
|
# This is useful for ensuring that the output matches the
|
|
# values generated by the "find" command
|
|
ls_tar() {
|
|
for f in $(tar -tf $1 | xargs realpath -ms --relative-to=.); do
|
|
if [[ "$f" != "." ]]; then
|
|
echo "/$f"
|
|
fi
|
|
done
|
|
}
|
|
|
|
mkdir image
|
|
touch baseFiles
|
|
baseEnvs='[]'
|
|
if [[ -n "$fromImage" ]]; then
|
|
echo "Unpacking base image..."
|
|
tar -C image -xpf "$fromImage"
|
|
|
|
# Store the layers and the environment variables from the base image
|
|
cat ./image/manifest.json | jq -r '.[0].Layers | .[]' > layer-list
|
|
configName="$(cat ./image/manifest.json | jq -r '.[0].Config')"
|
|
baseEnvs="$(cat "./image/$configName" | jq '.config.Env // []')"
|
|
|
|
# Extract the parentID from the manifest
|
|
if [[ -n "$fromImageName" ]] && [[ -n "$fromImageTag" ]]; then
|
|
parentID="$(
|
|
cat "image/manifest.json" |
|
|
jq -r '.[] | select(.RepoTags | contains([$desiredTag])) | rtrimstr(".json")' \
|
|
--arg desiredTag "$fromImageName:$fromImageTag"
|
|
)"
|
|
else
|
|
echo "From-image name or tag wasn't set. Reading the first ID."
|
|
parentID="$(cat "image/manifest.json" | jq -r '.[0].Config | rtrimstr(".json")')"
|
|
fi
|
|
|
|
# Otherwise do not import the base image configuration and manifest
|
|
chmod a+w image image/*.json
|
|
rm -f image/*.json
|
|
|
|
for l in image/*/layer.tar; do
|
|
ls_tar $l >> baseFiles
|
|
done
|
|
else
|
|
touch layer-list
|
|
fi
|
|
|
|
chmod -R ug+rw image
|
|
|
|
mkdir temp
|
|
cp ${layer}/* temp/
|
|
chmod ug+w temp/*
|
|
|
|
for dep in $(cat $layerClosure); do
|
|
find $dep >> layerFiles
|
|
done
|
|
|
|
echo "Adding layer..."
|
|
# Record the contents of the tarball with ls_tar.
|
|
ls_tar temp/layer.tar >> baseFiles
|
|
|
|
# Append nix/store directory to the layer so that when the layer is loaded in the
|
|
# image /nix/store has read permissions for non-root users.
|
|
# nix/store is added only if the layer has /nix/store paths in it.
|
|
if [ $(wc -l < $layerClosure) -gt 1 ] && [ $(grep -c -e "^/nix/store$" baseFiles) -eq 0 ]; then
|
|
mkdir -p nix/store
|
|
chmod -R 555 nix
|
|
echo "./nix" >> layerFiles
|
|
echo "./nix/store" >> layerFiles
|
|
fi
|
|
|
|
# Get the files in the new layer which were *not* present in
|
|
# the old layer, and record them as newFiles.
|
|
comm <(sort -n baseFiles|uniq) \
|
|
<(sort -n layerFiles|uniq|grep -v ${layer}) -1 -3 > newFiles
|
|
# Append the new files to the layer.
|
|
tar -rpf temp/layer.tar --hard-dereference --sort=name --mtime="@$SOURCE_DATE_EPOCH" \
|
|
--owner=0 --group=0 --no-recursion --verbatim-files-from --files-from newFiles
|
|
|
|
echo "Adding meta..."
|
|
|
|
# If we have a parentID, add it to the json metadata.
|
|
if [[ -n "$parentID" ]]; then
|
|
cat temp/json | jshon -s "$parentID" -i parent > tmpjson
|
|
mv tmpjson temp/json
|
|
fi
|
|
|
|
# Take the sha256 sum of the generated json and use it as the layer ID.
|
|
# Compute the size and add it to the json under the 'Size' field.
|
|
layerID=$(sha256sum temp/json|cut -d ' ' -f 1)
|
|
size=$(stat --printf="%s" temp/layer.tar)
|
|
cat temp/json | jshon -s "$layerID" -i id -n $size -i Size > tmpjson
|
|
mv tmpjson temp/json
|
|
|
|
# Use the temp folder we've been working on to create a new image.
|
|
mv temp image/$layerID
|
|
|
|
# Add the new layer ID to the end of the layer list
|
|
(
|
|
cat layer-list
|
|
# originally this used `sed -i "1i$layerID" layer-list`, but
|
|
# would fail if layer-list was completely empty.
|
|
echo "$layerID/layer.tar"
|
|
) | sponge layer-list
|
|
|
|
# Create image json and image manifest
|
|
imageJson=$(cat ${baseJson} | jq '.config.Env = $baseenv + .config.Env' --argjson baseenv "$baseEnvs")
|
|
imageJson=$(echo "$imageJson" | jq ". + {\"rootfs\": {\"diff_ids\": [], \"type\": \"layers\"}}")
|
|
manifestJson=$(jq -n "[{\"RepoTags\":[\"$imageName:$imageTag\"]}]")
|
|
|
|
for layerTar in $(cat ./layer-list); do
|
|
layerChecksum=$(sha256sum image/$layerTar | cut -d ' ' -f1)
|
|
imageJson=$(echo "$imageJson" | jq ".history |= . + [{\"created\": \"$(jq -r .created ${baseJson})\"}]")
|
|
# diff_ids order is from the bottom-most to top-most layer
|
|
imageJson=$(echo "$imageJson" | jq ".rootfs.diff_ids |= . + [\"sha256:$layerChecksum\"]")
|
|
manifestJson=$(echo "$manifestJson" | jq ".[0].Layers |= . + [\"$layerTar\"]")
|
|
done
|
|
|
|
imageJsonChecksum=$(echo "$imageJson" | sha256sum | cut -d ' ' -f1)
|
|
echo "$imageJson" > "image/$imageJsonChecksum.json"
|
|
manifestJson=$(echo "$manifestJson" | jq ".[0].Config = \"$imageJsonChecksum.json\"")
|
|
echo "$manifestJson" > image/manifest.json
|
|
|
|
# Store the json under the name image/repositories.
|
|
jshon -n object \
|
|
-n object -s "$layerID" -i "$imageTag" \
|
|
-i "$imageName" > image/repositories
|
|
|
|
# Make the image read-only.
|
|
chmod -R a-w image
|
|
|
|
echo "Cooking the image..."
|
|
tar -C image --hard-dereference --sort=name --mtime="@$SOURCE_DATE_EPOCH" --owner=0 --group=0 --xform s:'^./':: -c . | ${compress.compress} > $out
|
|
|
|
echo "Finished."
|
|
'';
|
|
|
|
in
|
|
checked result
|
|
);
|
|
|
|
# Merge the tarballs of images built with buildImage into a single
|
|
# tarball that contains all images. Running `docker load` on the resulting
|
|
# tarball will load the images into the docker daemon.
|
|
mergeImages = images: runCommand "merge-docker-images"
|
|
{
|
|
inherit images;
|
|
nativeBuildInputs = [ file jq ]
|
|
++ compressors.none.nativeInputs
|
|
++ compressors.gz.nativeInputs
|
|
++ compressors.zstd.nativeInputs;
|
|
} ''
|
|
mkdir image inputs
|
|
# Extract images
|
|
repos=()
|
|
manifests=()
|
|
last_image_mime="application/gzip"
|
|
for item in $images; do
|
|
name=$(basename $item)
|
|
mkdir inputs/$name
|
|
|
|
last_image_mime=$(file --mime-type -b $item)
|
|
case $last_image_mime in
|
|
"application/x-tar") ${compressors.none.decompress};;
|
|
"application/zstd") ${compressors.zstd.decompress};;
|
|
"application/gzip") ${compressors.gz.decompress};;
|
|
*) echo "error: unexpected layer type $last_image_mime" >&2; exit 1;;
|
|
esac < $item | tar -xC inputs/$name
|
|
|
|
if [ -f inputs/$name/repositories ]; then
|
|
repos+=(inputs/$name/repositories)
|
|
fi
|
|
if [ -f inputs/$name/manifest.json ]; then
|
|
manifests+=(inputs/$name/manifest.json)
|
|
fi
|
|
done
|
|
# Copy all layers from input images to output image directory
|
|
cp -R --update=none inputs/*/* image/
|
|
# Merge repositories objects and manifests
|
|
jq -s add "''${repos[@]}" > repositories
|
|
jq -s add "''${manifests[@]}" > manifest.json
|
|
# Replace output image repositories and manifest with merged versions
|
|
mv repositories image/repositories
|
|
mv manifest.json image/manifest.json
|
|
# Create tarball and gzip
|
|
tar -C image --hard-dereference --sort=name --mtime="@$SOURCE_DATE_EPOCH" --owner=0 --group=0 --xform s:'^./':: -c . | (
|
|
case $last_image_mime in
|
|
"application/x-tar") ${compressors.none.compress};;
|
|
"application/zstd") ${compressors.zstd.compress};;
|
|
"application/gzip") ${compressors.gz.compress};;
|
|
# `*)` not needed; already checked.
|
|
esac
|
|
) > $out
|
|
'';
|
|
|
|
|
|
# Provide a /etc/passwd and /etc/group that contain root and nobody.
|
|
# Useful when packaging binaries that insist on using nss to look up
|
|
# username/groups (like nginx).
|
|
# /bin/sh is fine to not exist, and provided by another shim.
|
|
inherit fakeNss; # alias
|
|
|
|
# This provides a /usr/bin/env, for shell scripts using the
|
|
# "#!/usr/bin/env executable" shebang.
|
|
usrBinEnv = runCommand "usr-bin-env" { } ''
|
|
mkdir -p $out/usr/bin
|
|
ln -s ${coreutils}/bin/env $out/usr/bin
|
|
'';
|
|
|
|
# This provides /bin/sh, pointing to bashInteractive.
|
|
# The use of bashInteractive here is intentional to support cases like `docker run -it <image_name>`, so keep these use cases in mind if making any changes to how this works.
|
|
binSh = runCommand "bin-sh" { } ''
|
|
mkdir -p $out/bin
|
|
ln -s ${bashInteractive}/bin/bash $out/bin/sh
|
|
'';
|
|
|
|
# This provides the ca bundle in common locations
|
|
caCertificates = runCommand "ca-certificates" { } ''
|
|
mkdir -p $out/etc/ssl/certs $out/etc/pki/tls/certs
|
|
# Old NixOS compatibility.
|
|
ln -s ${cacert}/etc/ssl/certs/ca-bundle.crt $out/etc/ssl/certs/ca-bundle.crt
|
|
# NixOS canonical location + Debian/Ubuntu/Arch/Gentoo compatibility.
|
|
ln -s ${cacert}/etc/ssl/certs/ca-bundle.crt $out/etc/ssl/certs/ca-certificates.crt
|
|
# CentOS/Fedora compatibility.
|
|
ln -s ${cacert}/etc/ssl/certs/ca-bundle.crt $out/etc/pki/tls/certs/ca-bundle.crt
|
|
'';
|
|
|
|
# Build an image and populate its nix database with the provided
|
|
# contents. The main purpose is to be able to use nix commands in
|
|
# the container.
|
|
# Be careful since this doesn't work well with multilayer.
|
|
# TODO: add the dependencies of the config json.
|
|
buildImageWithNixDb = args@{ copyToRoot ? contents, contents ? null, extraCommands ? "", ... }: (
|
|
buildImage (args // {
|
|
extraCommands = (mkDbExtraCommand copyToRoot) + extraCommands;
|
|
})
|
|
);
|
|
|
|
# TODO: add the dependencies of the config json.
|
|
buildLayeredImageWithNixDb = args@{ contents ? null, extraCommands ? "", ... }: (
|
|
buildLayeredImage (args // {
|
|
extraCommands = (mkDbExtraCommand contents) + extraCommands;
|
|
})
|
|
);
|
|
|
|
# Arguments are documented in ../../../doc/build-helpers/images/dockertools.section.md
|
|
streamLayeredImage = lib.makeOverridable (
|
|
{
|
|
name
|
|
, tag ? null
|
|
, fromImage ? null
|
|
, contents ? [ ]
|
|
, config ? { }
|
|
, architecture ? defaultArchitecture
|
|
, created ? "1970-01-01T00:00:01Z"
|
|
, uid ? 0
|
|
, gid ? 0
|
|
, uname ? "root"
|
|
, gname ? "root"
|
|
, maxLayers ? 100
|
|
, extraCommands ? ""
|
|
, fakeRootCommands ? ""
|
|
, enableFakechroot ? false
|
|
, includeStorePaths ? true
|
|
, passthru ? {}
|
|
,
|
|
}:
|
|
assert
|
|
(lib.assertMsg (maxLayers > 1)
|
|
"the maxLayers argument of dockerTools.buildLayeredImage function must be greather than 1 (current value: ${toString maxLayers})");
|
|
let
|
|
baseName = baseNameOf name;
|
|
|
|
streamScript = writePython3 "stream" { } ./stream_layered_image.py;
|
|
baseJson = writeText "${baseName}-base.json" (builtins.toJSON {
|
|
inherit config architecture;
|
|
os = "linux";
|
|
});
|
|
|
|
contentsList = if builtins.isList contents then contents else [ contents ];
|
|
bind-paths = builtins.toString (builtins.map (path: "--bind=${path}:${path}!") [
|
|
"/dev/"
|
|
"/proc/"
|
|
"/sys/"
|
|
"${builtins.storeDir}/"
|
|
"$out/layer.tar"
|
|
]);
|
|
|
|
# We store the customisation layer as a tarball, to make sure that
|
|
# things like permissions set on 'extraCommands' are not overridden
|
|
# by Nix. Then we precompute the sha256 for performance.
|
|
customisationLayer = symlinkJoin {
|
|
name = "${baseName}-customisation-layer";
|
|
paths = contentsList;
|
|
inherit extraCommands fakeRootCommands;
|
|
nativeBuildInputs = [
|
|
fakeroot
|
|
] ++ optionals enableFakechroot [
|
|
proot
|
|
];
|
|
postBuild = ''
|
|
mv $out old_out
|
|
(cd old_out; eval "$extraCommands" )
|
|
|
|
mkdir $out
|
|
${if enableFakechroot then ''
|
|
proot -r $PWD/old_out ${bind-paths} --pwd=/ fakeroot bash -c '
|
|
source $stdenv/setup
|
|
eval "$fakeRootCommands"
|
|
tar \
|
|
--sort name \
|
|
--exclude=./proc \
|
|
--exclude=./sys \
|
|
--exclude=.${builtins.storeDir} \
|
|
--numeric-owner --mtime "@$SOURCE_DATE_EPOCH" \
|
|
--hard-dereference \
|
|
-cf $out/layer.tar .
|
|
'
|
|
'' else ''
|
|
fakeroot bash -c '
|
|
source $stdenv/setup
|
|
cd old_out
|
|
eval "$fakeRootCommands"
|
|
tar \
|
|
--sort name \
|
|
--numeric-owner --mtime "@$SOURCE_DATE_EPOCH" \
|
|
--hard-dereference \
|
|
-cf $out/layer.tar .
|
|
'
|
|
''}
|
|
sha256sum $out/layer.tar \
|
|
| cut -f 1 -d ' ' \
|
|
> $out/checksum
|
|
'';
|
|
};
|
|
|
|
closureRoots = lib.optionals includeStorePaths /* normally true */ (
|
|
[ baseJson customisationLayer ]
|
|
);
|
|
overallClosure = writeText "closure" (lib.concatStringsSep " " closureRoots);
|
|
|
|
# These derivations are only created as implementation details of docker-tools,
|
|
# so they'll be excluded from the created images.
|
|
unnecessaryDrvs = [ baseJson overallClosure customisationLayer ];
|
|
|
|
conf = runCommand "${baseName}-conf.json"
|
|
{
|
|
inherit fromImage maxLayers created uid gid uname gname;
|
|
imageName = lib.toLower name;
|
|
preferLocalBuild = true;
|
|
passthru.imageTag =
|
|
if tag != null
|
|
then tag
|
|
else
|
|
lib.head (lib.strings.splitString "-" (baseNameOf (builtins.unsafeDiscardStringContext conf.outPath)));
|
|
paths = buildPackages.referencesByPopularity overallClosure;
|
|
nativeBuildInputs = [ jq ];
|
|
} ''
|
|
${if (tag == null) then ''
|
|
outName="$(basename "$out")"
|
|
outHash=$(echo "$outName" | cut -d - -f 1)
|
|
|
|
imageTag=$outHash
|
|
'' else ''
|
|
imageTag="${tag}"
|
|
''}
|
|
|
|
# convert "created" to iso format
|
|
if [[ "$created" != "now" ]]; then
|
|
created="$(date -Iseconds -d "$created")"
|
|
fi
|
|
|
|
paths() {
|
|
cat $paths ${lib.concatMapStringsSep " "
|
|
(path: "| (grep -v ${path} || true)")
|
|
unnecessaryDrvs}
|
|
}
|
|
|
|
# Compute the number of layers that are already used by a potential
|
|
# 'fromImage' as well as the customization layer. Ensure that there is
|
|
# still at least one layer available to store the image contents.
|
|
usedLayers=0
|
|
|
|
# subtract number of base image layers
|
|
if [[ -n "$fromImage" ]]; then
|
|
(( usedLayers += $(tar -xOf "$fromImage" manifest.json | jq '.[0].Layers | length') ))
|
|
fi
|
|
|
|
# one layer will be taken up by the customisation layer
|
|
(( usedLayers += 1 ))
|
|
|
|
if ! (( $usedLayers < $maxLayers )); then
|
|
echo >&2 "Error: usedLayers $usedLayers layers to store 'fromImage' and" \
|
|
"'extraCommands', but only maxLayers=$maxLayers were" \
|
|
"allowed. At least 1 layer is required to store contents."
|
|
exit 1
|
|
fi
|
|
availableLayers=$(( maxLayers - usedLayers ))
|
|
|
|
# Create $maxLayers worth of Docker Layers, one layer per store path
|
|
# unless there are more paths than $maxLayers. In that case, create
|
|
# $maxLayers-1 for the most popular layers, and smush the remainaing
|
|
# store paths in to one final layer.
|
|
#
|
|
# The following code is fiddly w.r.t. ensuring every layer is
|
|
# created, and that no paths are missed. If you change the
|
|
# following lines, double-check that your code behaves properly
|
|
# when the number of layers equals:
|
|
# maxLayers-1, maxLayers, and maxLayers+1, 0
|
|
paths |
|
|
jq -sR '
|
|
rtrimstr("\n") | split("\n")
|
|
| (.[:$maxLayers-1] | map([.])) + [ .[$maxLayers-1:] ]
|
|
| map(select(length > 0))
|
|
' \
|
|
--argjson maxLayers "$availableLayers" > store_layers.json
|
|
|
|
# The index on $store_layers is necessary because the --slurpfile
|
|
# automatically reads the file as an array.
|
|
cat ${baseJson} | jq '
|
|
. + {
|
|
"store_dir": $store_dir,
|
|
"from_image": $from_image,
|
|
"store_layers": $store_layers[0],
|
|
"customisation_layer", $customisation_layer,
|
|
"repo_tag": $repo_tag,
|
|
"created": $created,
|
|
"uid": $uid,
|
|
"gid": $gid,
|
|
"uname": $uname,
|
|
"gname": $gname
|
|
}
|
|
' --arg store_dir "${storeDir}" \
|
|
--argjson from_image ${if fromImage == null then "null" else "'\"${fromImage}\"'"} \
|
|
--slurpfile store_layers store_layers.json \
|
|
--arg customisation_layer ${customisationLayer} \
|
|
--arg repo_tag "$imageName:$imageTag" \
|
|
--arg created "$created" \
|
|
--arg uid "$uid" \
|
|
--arg gid "$gid" \
|
|
--arg uname "$uname" \
|
|
--arg gname "$gname" |
|
|
tee $out
|
|
'';
|
|
|
|
result = runCommand "stream-${baseName}"
|
|
{
|
|
inherit (conf) imageName;
|
|
preferLocalBuild = true;
|
|
passthru = passthru // {
|
|
inherit (conf) imageTag;
|
|
|
|
# Distinguish tarballs and exes at the Nix level so functions that
|
|
# take images can know in advance how the image is supposed to be used.
|
|
isExe = true;
|
|
};
|
|
nativeBuildInputs = [ makeWrapper ];
|
|
} ''
|
|
makeWrapper ${streamScript} $out --add-flags ${conf}
|
|
'';
|
|
in
|
|
result
|
|
);
|
|
|
|
# This function streams a docker image that behaves like a nix-shell for a derivation
|
|
streamNixShellImage =
|
|
{ # The derivation whose environment this docker image should be based on
|
|
drv
|
|
, # Image Name
|
|
name ? drv.name + "-env"
|
|
, # Image tag, the Nix's output hash will be used if null
|
|
tag ? null
|
|
, # User id to run the container as. Defaults to 1000, because many
|
|
# binaries don't like to be run as root
|
|
uid ? 1000
|
|
, # Group id to run the container as, see also uid
|
|
gid ? 1000
|
|
, # The home directory of the user
|
|
homeDirectory ? "/build"
|
|
, # The path to the bash binary to use as the shell. See `NIX_BUILD_SHELL` in `man nix-shell`
|
|
shell ? bashInteractive + "/bin/bash"
|
|
, # Run this command in the environment of the derivation, in an interactive shell. See `--command` in `man nix-shell`
|
|
command ? null
|
|
, # Same as `command`, but runs the command in a non-interactive shell instead. See `--run` in `man nix-shell`
|
|
run ? null
|
|
}:
|
|
assert lib.assertMsg (! (drv.drvAttrs.__structuredAttrs or false))
|
|
"streamNixShellImage: Does not work with the derivation ${drv.name} because it uses __structuredAttrs";
|
|
assert lib.assertMsg (command == null || run == null)
|
|
"streamNixShellImage: Can't specify both command and run";
|
|
let
|
|
|
|
# A binary that calls the command to build the derivation
|
|
builder = writeShellScriptBin "buildDerivation" ''
|
|
exec ${lib.escapeShellArg (stringValue drv.drvAttrs.builder)} ${lib.escapeShellArgs (map stringValue drv.drvAttrs.args)}
|
|
'';
|
|
|
|
staticPath = "${dirOf shell}:${lib.makeBinPath [ builder ]}";
|
|
|
|
# https://github.com/NixOS/nix/blob/2.8.0/src/nix-build/nix-build.cc#L493-L526
|
|
rcfile = writeText "nix-shell-rc" ''
|
|
unset PATH
|
|
dontAddDisableDepTrack=1
|
|
# TODO: https://github.com/NixOS/nix/blob/2.8.0/src/nix-build/nix-build.cc#L506
|
|
[ -e $stdenv/setup ] && source $stdenv/setup
|
|
PATH=${staticPath}:"$PATH"
|
|
SHELL=${lib.escapeShellArg shell}
|
|
BASH=${lib.escapeShellArg shell}
|
|
set +e
|
|
[ -n "$PS1" -a -z "$NIX_SHELL_PRESERVE_PROMPT" ] && PS1='\n\[\033[1;32m\][nix-shell:\w]\$\[\033[0m\] '
|
|
if [ "$(type -t runHook)" = function ]; then
|
|
runHook shellHook
|
|
fi
|
|
unset NIX_ENFORCE_PURITY
|
|
shopt -u nullglob
|
|
shopt -s execfail
|
|
${optionalString (command != null || run != null) ''
|
|
${optionalString (command != null) command}
|
|
${optionalString (run != null) run}
|
|
exit
|
|
''}
|
|
'';
|
|
|
|
# https://github.com/NixOS/nix/blob/2.8.0/src/libstore/globals.hh#L464-L465
|
|
sandboxBuildDir = "/build";
|
|
|
|
# This function closely mirrors what this Nix code does:
|
|
# https://github.com/NixOS/nix/blob/2.8.0/src/libexpr/primops.cc#L1102
|
|
# https://github.com/NixOS/nix/blob/2.8.0/src/libexpr/eval.cc#L1981-L2036
|
|
stringValue = value:
|
|
# We can't just use `toString` on all derivation attributes because that
|
|
# would not put path literals in the closure. So we explicitly copy
|
|
# those into the store here
|
|
if builtins.typeOf value == "path" then "${value}"
|
|
else if builtins.typeOf value == "list" then toString (map stringValue value)
|
|
else toString value;
|
|
|
|
# https://github.com/NixOS/nix/blob/2.8.0/src/libstore/build/local-derivation-goal.cc#L992-L1004
|
|
drvEnv = lib.mapAttrs' (name: value:
|
|
let str = stringValue value;
|
|
in if lib.elem name (drv.drvAttrs.passAsFile or [])
|
|
then lib.nameValuePair "${name}Path" (writeText "pass-as-text-${name}" str)
|
|
else lib.nameValuePair name str
|
|
) drv.drvAttrs //
|
|
# A mapping from output name to the nix store path where they should end up
|
|
# https://github.com/NixOS/nix/blob/2.8.0/src/libexpr/primops.cc#L1253
|
|
lib.genAttrs drv.outputs (output: builtins.unsafeDiscardStringContext drv.${output}.outPath);
|
|
|
|
# Environment variables set in the image
|
|
envVars = {
|
|
|
|
# Root certificates for internet access
|
|
SSL_CERT_FILE = "${cacert}/etc/ssl/certs/ca-bundle.crt";
|
|
NIX_SSL_CERT_FILE = "${cacert}/etc/ssl/certs/ca-bundle.crt";
|
|
|
|
# https://github.com/NixOS/nix/blob/2.8.0/src/libstore/build/local-derivation-goal.cc#L1027-L1030
|
|
# PATH = "/path-not-set";
|
|
# Allows calling bash and `buildDerivation` as the Cmd
|
|
PATH = staticPath;
|
|
|
|
# https://github.com/NixOS/nix/blob/2.8.0/src/libstore/build/local-derivation-goal.cc#L1032-L1038
|
|
HOME = homeDirectory;
|
|
|
|
# https://github.com/NixOS/nix/blob/2.8.0/src/libstore/build/local-derivation-goal.cc#L1040-L1044
|
|
NIX_STORE = storeDir;
|
|
|
|
# https://github.com/NixOS/nix/blob/2.8.0/src/libstore/build/local-derivation-goal.cc#L1046-L1047
|
|
# TODO: Make configurable?
|
|
NIX_BUILD_CORES = "1";
|
|
|
|
} // drvEnv // {
|
|
|
|
# https://github.com/NixOS/nix/blob/2.8.0/src/libstore/build/local-derivation-goal.cc#L1008-L1010
|
|
NIX_BUILD_TOP = sandboxBuildDir;
|
|
|
|
# https://github.com/NixOS/nix/blob/2.8.0/src/libstore/build/local-derivation-goal.cc#L1012-L1013
|
|
TMPDIR = sandboxBuildDir;
|
|
TEMPDIR = sandboxBuildDir;
|
|
TMP = sandboxBuildDir;
|
|
TEMP = sandboxBuildDir;
|
|
|
|
# https://github.com/NixOS/nix/blob/2.8.0/src/libstore/build/local-derivation-goal.cc#L1015-L1019
|
|
PWD = sandboxBuildDir;
|
|
|
|
# https://github.com/NixOS/nix/blob/2.8.0/src/libstore/build/local-derivation-goal.cc#L1071-L1074
|
|
# We don't set it here because the output here isn't handled in any special way
|
|
# NIX_LOG_FD = "2";
|
|
|
|
# https://github.com/NixOS/nix/blob/2.8.0/src/libstore/build/local-derivation-goal.cc#L1076-L1077
|
|
TERM = "xterm-256color";
|
|
};
|
|
|
|
|
|
in streamLayeredImage {
|
|
inherit name tag;
|
|
contents = [
|
|
binSh
|
|
usrBinEnv
|
|
(fakeNss.override {
|
|
# Allows programs to look up the build user's home directory
|
|
# https://github.com/NixOS/nix/blob/ffe155abd36366a870482625543f9bf924a58281/src/libstore/build/local-derivation-goal.cc#L906-L910
|
|
# Slightly differs however: We use the passed-in homeDirectory instead of sandboxBuildDir.
|
|
# We're doing this because it's arguably a bug in Nix that sandboxBuildDir is used here: https://github.com/NixOS/nix/issues/6379
|
|
extraPasswdLines = [
|
|
"nixbld:x:${toString uid}:${toString gid}:Build user:${homeDirectory}:/noshell"
|
|
];
|
|
extraGroupLines = [
|
|
"nixbld:!:${toString gid}:"
|
|
];
|
|
})
|
|
];
|
|
|
|
fakeRootCommands = ''
|
|
# Effectively a single-user installation of Nix, giving the user full
|
|
# control over the Nix store. Needed for building the derivation this
|
|
# shell is for, but also in case one wants to use Nix inside the
|
|
# image
|
|
mkdir -p ./nix/{store,var/nix} ./etc/nix
|
|
chown -R ${toString uid}:${toString gid} ./nix ./etc/nix
|
|
|
|
# Gives the user control over the build directory
|
|
mkdir -p .${sandboxBuildDir}
|
|
chown -R ${toString uid}:${toString gid} .${sandboxBuildDir}
|
|
'';
|
|
|
|
# Run this image as the given uid/gid
|
|
config.User = "${toString uid}:${toString gid}";
|
|
config.Cmd =
|
|
# https://github.com/NixOS/nix/blob/2.8.0/src/nix-build/nix-build.cc#L185-L186
|
|
# https://github.com/NixOS/nix/blob/2.8.0/src/nix-build/nix-build.cc#L534-L536
|
|
if run == null
|
|
then [ shell "--rcfile" rcfile ]
|
|
else [ shell rcfile ];
|
|
config.WorkingDir = sandboxBuildDir;
|
|
config.Env = lib.mapAttrsToList (name: value: "${name}=${value}") envVars;
|
|
};
|
|
|
|
# Wrapper around streamNixShellImage to build an image from the result
|
|
buildNixShellImage = { drv, compressor ? "gz", ... }@args:
|
|
let
|
|
stream = streamNixShellImage (builtins.removeAttrs args ["compressor"]);
|
|
compress = compressorForImage compressor drv.name;
|
|
in
|
|
runCommand "${drv.name}-env.tar${compress.ext}"
|
|
{
|
|
inherit (stream) imageName;
|
|
passthru = { inherit (stream) imageTag; };
|
|
nativeBuildInputs = compress.nativeInputs;
|
|
} "${stream} | ${compress.compress} > $out";
|
|
}
|