From ba3edc5638f656b73592a44151fd9341a5935031 Mon Sep 17 00:00:00 2001 From: Florian Klink Date: Sat, 23 Sep 2023 17:34:01 +0300 Subject: feat(tvix/tests): add basic plumbing for integration tests This adds a basic skeleton to test various tvix components in combination. As a first start, we test the virtiofs integration, by seeding the tvix- store with some data, booting a VM, and listing the contents from there. Change-Id: Ice6516d0eb508d19ea8fabefee860a0950046171 Reviewed-on: https://cl.tvl.fyi/c/depot/+/9449 Autosubmit: flokli Tested-by: BuildkiteCI Reviewed-by: Connor Brewster --- tvix/tests/README.md | 115 ++++++++++++++++++++++++++++++++++++++++ tvix/tests/default.nix | 137 ++++++++++++++++++++++++++++++++++++++++++++++++ tvix/tests/tvix-init.go | 85 ++++++++++++++++++++++++++++++ 3 files changed, 337 insertions(+) create mode 100644 tvix/tests/README.md create mode 100644 tvix/tests/default.nix create mode 100644 tvix/tests/tvix-init.go (limited to 'tvix/tests') diff --git a/tvix/tests/README.md b/tvix/tests/README.md new file mode 100644 index 000000000000..b079a85dbddd --- /dev/null +++ b/tvix/tests/README.md @@ -0,0 +1,115 @@ +# tvix/tests + +This directory provides a bunch of integration tests using tvix. + +The currently most interesting (and only) ones ;-) are using a cloud-hypervisor +VM. + +## //tvix/tests:test-docs +This is a test encapsulated in a nix build. +It seeds a tvix-store with the tvix docs, then starts a VM, asks it to list all +files in /nix/store, and ensures the store path is present, which acts as a +nice smoketest. + +## //tvix/tests:runVM +A script spinning up a `tvix-store virtiofs` daemon, then starting a cloud- +hypervisor VM. + +The cloud-hypervisor VM is using a (semi-)minimal kernel image with virtiofs +support, and a custom initrd (using u-root). It supports various command line +options, to be able to do VM tests, act as an interactive shell or exec a binary +from a closure. + +It supports the following env vars: + - `CH_NUM_CPUS=1` controls the number of CPUs available to the VM + - `CH_MEM_SIZE=512M` controls the memory availabe to the VM + - `CH_CMDLINE=` controls the kernel cmdline (which can be used to control the + boot) + +### Usage +First, ensure you have `tvix-store` in `$PATH`, as that's what `run-tvix-vm` +expects: + +Assuming you ran `cargo build --profile=release-with-debug` before, and are in +the `tvix` directory: + +``` +export PATH=$PATH:$PWD/target/release-with-debug +``` + +Secondly, configure tvix to use the local backend: + +``` +export BLOB_SERVICE_ADDR=sled://$PWD/blobs.sled +export DIRECTORY_SERVICE_ADDR=sled://$PWD/directories.sled +export PATH_INFO_SERVICE_ADDR=sled://$PWD/pathinfo.sled +``` + +Potentially copy some data into tvix-store (via nar-bridge): + +``` +mg run //tvix:store -- daemon & +mg run //tvix:nar-bridge -- & +rm -Rf ~/.cache/nix; nix copy --to http://localhost:9000\?compression\=none $(mg build //third_party/nixpkgs:hello) +pkill nar-bridge; pkill tvix-store +``` + +#### Interactive shell +Run the VM like this: + +``` +CH_CMDLINE=tvix.shell mg run //tvix/tests:runVM -- +``` + +You'll get dropped into a shell, from which you can list the store contents: + +``` +[ 0.282381] Run /init as init process +2023/09/24 13:03:38 Welcome to u-root! + _ + _ _ _ __ ___ ___ | |_ + | | | |____| '__/ _ \ / _ \| __| + | |_| |____| | | (_) | (_) | |_ + \__,_| |_| \___/ \___/ \__| + +2023/09/24 13:03:38 Running tvix-init… +2023/09/24 13:03:38 Creating /nix/store +2023/09/24 13:03:38 Mounting… +2023/09/24 13:03:38 Invoking shell +… +/# ls -la /nix/store/ +dr-xr-xr-x root 0 0 Jan 1 00:00 . +dr-xr-xr-x root 0 989 Jan 1 00:00 aw2fw9ag10wr9pf0qk4nk5sxi0q0bn56-glibc-2.37-8 +dr-xr-xr-x root 0 3 Jan 1 00:00 jbwb8d8l28lg9z0xzl784wyb9vlbwss6-xgcc-12.3.0-libgcc +dr-xr-xr-x root 0 82 Jan 1 00:00 k8ivghpggjrq1n49xp8sj116i4sh8lia-libidn2-2.3.4 +dr-xr-xr-x root 0 141 Jan 1 00:00 mdi7lvrn2mx7rfzv3fdq3v5yw8swiks6-hello-2.12.1 +dr-xr-xr-x root 0 5 Jan 1 00:00 s2gi8pfjszy6rq3ydx0z1vwbbskw994i-libunistring-1.1 +``` + +Once you're done, run `poweroff` to turn off the VM. + +#### Execute a specific binary +Run the VM like this: + +``` +hello_cmd=$(mg build //third_party/nixpkgs:hello)/bin/hello +CH_CMDLINE=tvix.exec=$hello_cmd mg run //tvix/tests:runVM -- +``` + +Observe it executing the file (and closure) from the tvix-store: + +``` +2023/09/24 13:06:13 Welcome to u-root! + _ + _ _ _ __ ___ ___ | |_ + | | | |____| '__/ _ \ / _ \| __| + | |_| |____| | | (_) | (_) | |_ + \__,_| |_| \___/ \___/ \__| + +2023/09/24 13:06:13 Running tvix-init… +2023/09/24 13:06:13 Creating /nix/store +2023/09/24 13:06:13 Mounting… +2023/09/24 13:06:13 Invoking /nix/store/mdi7lvrn2mx7rfzv3fdq3v5yw8swiks6-hello-2.12.1/bin/hello +… +Hello, world! +``` \ No newline at end of file diff --git a/tvix/tests/default.nix b/tvix/tests/default.nix new file mode 100644 index 000000000000..9e9a22a66221 --- /dev/null +++ b/tvix/tests/default.nix @@ -0,0 +1,137 @@ +{ depot, pkgs, ... }: + +rec { + # A binary that sets up /nix/store from virtiofs, lists all store paths, and + # powers off the machine. + tvix-init = depot.nix.buildGo.program { + name = "tvix-init"; + srcs = [ + ./tvix-init.go + ]; + }; + + # A kernel with virtiofs support baked in + kernel = pkgs.buildLinux ({ } // { + inherit (pkgs.linuxPackages_latest.kernel) src version modDirVersion; + autoModules = false; + kernelPreferBuiltin = true; + ignoreConfigErrors = true; + kernelPatches = [ ]; + structuredExtraConfig = with pkgs.lib.kernel; { + FUSE_FS = option yes; + DAX_DRIVER = option yes; + DAX = option yes; + FS_DAX = option yes; + VIRTIO_FS = option yes; + VIRTIO = option yes; + ZONE_DEVICE = option yes; + }; + }); + + # A build framework for minimal initrds + uroot = pkgs.buildGoModule { + pname = "u-root"; + version = "unstable-2023-09-20"; + src = pkgs.fetchFromGitHub { + owner = "u-root"; + repo = "u-root"; + rev = "72921548ce2e88c4c5b62e83c717cbd834b58067"; + hash = "sha256-fEoUGqh6ZXprtSpJ55MeuSFe7L5A/rkIIVLCwxbPHzE="; + }; + vendorHash = null; + + doCheck = false; # Some tests invoke /bin/bash + }; + + # Use u-root to build a initrd with our tvix-init inside. + initrd = pkgs.stdenv.mkDerivation { + name = "initrd.cpio"; + nativeBuildInputs = [ pkgs.go ]; + # https://github.com/u-root/u-root/issues/2466 + buildCommand = '' + mkdir -p /tmp/go/src/github.com/u-root/ + cp -R ${uroot.src} /tmp/go/src/github.com/u-root/u-root + cd /tmp/go/src/github.com/u-root/u-root + chmod +w . + cp ${tvix-init}/bin/tvix-init tvix-init + + export HOME=$(mktemp -d) + export GOROOT="$(go env GOROOT)" + + GO111MODULE=off GOPATH=/tmp/go GOPROXY=off ${uroot}/bin/u-root -files ./tvix-init -uinitcmd "/tvix-init" -o $out + ''; + }; + + # Start a `tvix-store` virtiofs daemon from $PATH, then a cloud-hypervisor + # pointed to it. + # Supports the following env vars (and defaults) + # CH_NUM_CPUS=1 + # CH_MEM_SIZE=512M + # CH_CMDLINE="" + runVM = pkgs.writers.writeBashBin "run-tvix-vm" '' + tempdir=$(mktemp -d) + + cleanup() { + kill $virtiofsd_pid + if [[ -n ''${work_dir-} ]]; then + chmod -R u+rw "$tempdir" + rm -rf "$tempdir" + fi + } + trap cleanup EXIT + + # Spin up the virtiofs daemon + tvix-store virtiofs -l $tempdir/tvix.sock & + virtiofsd_pid=$! + + # Wait for the socket to exist. + until [ -e $tempdir/tvix.sock ]; do sleep 0.1; done + + CH_NUM_CPUS="''${CH_NUM_CPUS:-1}" + CH_MEM_SIZE="''${CH_MEM_SIZE:-512M}" + CH_CMDLINE="''${CH_CMDLINE:-}" + + # spin up cloud_hypervisor + ${pkgs.cloud-hypervisor}/bin/cloud-hypervisor \ + --cpus boot=$CH_NUM_CPU \ + --memory mergeable=on,shared=on,size=$CH_MEM_SIZE \ + --console null \ + --serial tty \ + --kernel ${kernel.dev}/vmlinux \ + --initramfs ${initrd} \ + --cmdline "console=ttyS0 $CH_CMDLINE" \ + --fs tag=tvix,socket=$tempdir/tvix.sock,num_queues=1,queue_size=512 + ''; + + # Seed a tvix-store with the tvix docs, then start a VM and search for the + # store path in the output. + test-docs = pkgs.stdenv.mkDerivation { + name = "run-vm"; + nativeBuildInputs = [ + depot.tvix.store + ]; + buildCommand = '' + touch $out + + # Configure tvix to put data in the local working directory + export BLOB_SERVICE_ADDR=sled://$PWD/blobs.sled + export DIRECTORY_SERVICE_ADDR=sled://$PWD/directories.sled + export PATH_INFO_SERVICE_ADDR=sled://$PWD/pathinfo.sled + + # Seed the tvix store with some data + # Create a `docs` directory with the contents from ../docs + # Make sure it still is called "docs" when calling import, so we can + # predict the store path. + cp -R ${../docs} docs + outpath=$(tvix-store import docs) + + echo "Store contents imported to $outpath" + + CH_CMDLINE="tvix.find" ${runVM}/bin/run-tvix-vm 2>&1 | tee output.txt + grep ${../docs} output.txt + ''; + requiredSystemFeatures = [ "kvm" ]; + }; + + meta.ci.targets = [ "test-docs" ]; +} diff --git a/tvix/tests/tvix-init.go b/tvix/tests/tvix-init.go new file mode 100644 index 000000000000..a81001159ae2 --- /dev/null +++ b/tvix/tests/tvix-init.go @@ -0,0 +1,85 @@ +package main + +import ( + "log" + "os" + "os/exec" + "strings" + "syscall" +) + +// run the given command, connecting std{in,err,out} with the OS one. +func run(args ...string) error { + cmd := exec.Command(args[0], args[1:]...) + cmd.Stdin = os.Stdin + cmd.Stderr = os.Stderr + cmd.Stdout = os.Stdout + + return cmd.Run() +} + +// parse the cmdline, return a map[string]string. +func parseCmdline(cmdline string) map[string]string { + line := strings.TrimSuffix(cmdline, "\n") + fields := strings.Fields(line) + out := make(map[string]string, 0) + + for _, arg := range fields { + kv := strings.SplitN(arg, "=", 2) + switch len(kv) { + case 1: + out[kv[0]] = "" + case 2: + out[kv[0]] = kv[1] + } + } + + return out +} + +func main() { + log.Println("Running tvix-init…") + + log.Println("Creating /nix/store") + os.MkdirAll("/nix/store", os.ModePerm) + + cmdline, err := os.ReadFile("/proc/cmdline") + if err != nil { + log.Printf("Failed to read cmdline: %s\n", err) + } + cmdlineFields := parseCmdline(string(cmdline)) + + log.Println("Mounting…") + if err := run("mount", "-t", "virtiofs", "tvix", "/nix/store", "-o", "ro"); err != nil { + log.Printf("Failed to run mount: %v\n", err) + } + + // If tvix.find is set, invoke find /nix/store + if _, ok := cmdlineFields["tvix.find"]; ok { + log.Println("Listing…") + if err := run("find", "/nix/store"); err != nil { + log.Printf("Failed to run find command: %s\n", err) + } + } + + // If tvix.shell is set, invoke the elvish shell + if v, ok := cmdlineFields["tvix.shell"]; ok { + log.Printf("Invoking shell%s\n…", v) + if err := run("elvish"); err != nil { + log.Printf("Failed to run shell: %s\n", err) + } + } + + // If tvix.exec is set, invoke the binary specified + if v, ok := cmdlineFields["tvix.exec"]; ok { + log.Printf("Invoking %s\n…", v) + if err := syscall.Exec(v, []string{v}, []string{}); err != nil { + log.Printf("Failed to exec: %s\n", err) + } + } + + log.Println("Powering off") + if err := run("poweroff"); err != nil { + log.Printf("Failed to run command: %v\n", err) + } +} -- cgit 1.4.1