treewide: replace hardcoded runfiles paths

We hardcoded some of the runfiles paths to find specific files. This replaces the hardcoded paths by a call to rlocationpath. This prevents running a target without the correct dependencies at build time instead of at runtime

Change-Id: I7ce56935ac80be6b28b824ccb0781ab401bd6521
Reviewed-on: https://review.monogon.dev/c/monogon/+/3301
Reviewed-by: Serge Bazanski <serge@monogon.tech>
Tested-by: Jenkins CI
diff --git a/metropolis/installer/test/run_test.go b/metropolis/installer/test/run_test.go
new file mode 100644
index 0000000..fef8e20
--- /dev/null
+++ b/metropolis/installer/test/run_test.go
@@ -0,0 +1,327 @@
+// Copyright 2020 The Monogon Project Authors.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// This package runs the installer image in a VM provided with an empty block
+// device. It then examines the installer console output and the blok device to
+// determine whether the installation process completed without issue.
+package installer
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"log"
+	"os"
+	"path/filepath"
+	"syscall"
+	"testing"
+	"time"
+
+	"github.com/bazelbuild/rules_go/go/runfiles"
+	"github.com/diskfs/go-diskfs"
+	"github.com/diskfs/go-diskfs/disk"
+	"github.com/diskfs/go-diskfs/partition/gpt"
+
+	"source.monogon.dev/metropolis/proto/api"
+
+	mctl "source.monogon.dev/metropolis/cli/metroctl/core"
+	"source.monogon.dev/metropolis/node/build/mkimage/osimage"
+	"source.monogon.dev/osbase/cmd"
+)
+
+var (
+	// These are filled by bazel at linking time with the canonical path of
+	// their corresponding file. Inside the init function we resolve it
+	// with the rules_go runfiles package to the real path.
+	xOvmfCodePath  string
+	xOvmfVarsPath  string
+	xQemuPath      string
+	xInstallerPath string
+	xBundlePath    string
+)
+
+func init() {
+	var err error
+	for _, path := range []*string{
+		&xOvmfCodePath, &xOvmfVarsPath, &xQemuPath,
+		&xInstallerPath, &xBundlePath,
+	} {
+		*path, err = runfiles.Rlocation(*path)
+		if err != nil {
+			panic(err)
+		}
+	}
+}
+
+// Each variable in this block points to either a test dependency or a side
+// effect. These variables are initialized in TestMain using Bazel.
+var (
+	// installerImage is a filesystem path pointing at the installer image that
+	// is generated during the test, and is removed afterwards.
+	installerImage string
+)
+
+// runQemu starts a new QEMU process, expecting the given output to appear
+// in any line printed. It returns true, if the expected string was found,
+// and false otherwise.
+//
+// QEMU is killed shortly after the string is found, or when the context is
+// cancelled.
+func runQemu(ctx context.Context, args []string, expectedOutput string) (bool, error) {
+	defaultArgs := []string{
+		"-machine", "q35", "-accel", "kvm", "-nographic", "-nodefaults",
+		"-m", "512",
+		"-smp", "2",
+		"-cpu", "host",
+		"-drive", "if=pflash,format=raw,snapshot=on,file=" + xOvmfCodePath,
+		"-drive", "if=pflash,format=raw,readonly=on,file=" + xOvmfVarsPath,
+		"-serial", "stdio",
+		"-no-reboot",
+	}
+	qemuArgs := append(defaultArgs, args...)
+	pf := cmd.TerminateIfFound(expectedOutput, nil)
+	return cmd.RunCommand(ctx, xQemuPath, qemuArgs, pf)
+}
+
+// runQemuWithInstaller runs the Metropolis Installer in a qemu, performing the
+// same search-through-std{out,err} as runQemu.
+func runQemuWithInstaller(ctx context.Context, args []string, expectedOutput string) (bool, error) {
+	args = append(args, "-drive", "if=virtio,format=raw,snapshot=on,cache=unsafe,file="+installerImage)
+	return runQemu(ctx, args, expectedOutput)
+}
+
+// getStorage creates a sparse file, given a size expressed in mebibytes, and
+// returns a path to that file. It may return an error.
+func getStorage(size int64) (string, error) {
+	nodeStorageDir, err := os.MkdirTemp(os.Getenv("TEST_TMPDIR"), "storage")
+	if err != nil {
+		return "", err
+	}
+	nodeStorage := filepath.Join(nodeStorageDir, "stor.img")
+	image, err := os.Create(nodeStorage)
+	if err != nil {
+		return "", fmt.Errorf("couldn't create the block device image at %q: %w", nodeStorage, err)
+	}
+	if err := syscall.Ftruncate(int(image.Fd()), size*1024*1024); err != nil {
+		return "", fmt.Errorf("couldn't resize the block device image at %q: %w", nodeStorage, err)
+	}
+	image.Close()
+	return nodeStorage, nil
+}
+
+// qemuDriveParam returns QEMU parameters required to run it with a
+// raw-format image at path.
+func qemuDriveParam(path string) []string {
+	return []string{"-drive", "if=virtio,format=raw,snapshot=off,cache=unsafe,file=" + path}
+}
+
+// checkEspContents verifies the presence of the EFI payload inside of image's
+// first partition. It returns nil on success.
+func checkEspContents(image *disk.Disk) error {
+	// Get the ESP.
+	fs, err := image.GetFilesystem(1)
+	if err != nil {
+		return fmt.Errorf("couldn't read the installer ESP: %w", err)
+	}
+	// Make sure the EFI payload exists by attempting to open it.
+	efiPayload, err := fs.OpenFile(osimage.EFIPayloadPath, os.O_RDONLY)
+	if err != nil {
+		return fmt.Errorf("couldn't open the installer's EFI Payload at %q: %w", osimage.EFIPayloadPath, err)
+	}
+	efiPayload.Close()
+	return nil
+}
+
+func TestMain(m *testing.M) {
+	installerImage = filepath.Join(os.Getenv("TEST_TMPDIR"), "installer.img")
+
+	installer, err := os.ReadFile(xInstallerPath)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	bundle, err := os.ReadFile(xBundlePath)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	iargs := mctl.MakeInstallerImageArgs{
+		Installer:  bytes.NewReader(installer),
+		TargetPath: installerImage,
+		NodeParams: &api.NodeParameters{},
+		Bundle:     bytes.NewReader(bundle),
+	}
+	if err := mctl.MakeInstallerImage(iargs); err != nil {
+		log.Fatalf("Couldn't create the installer image at %q: %v", installerImage, err)
+	}
+	// With common dependencies set up, run the tests.
+	code := m.Run()
+	// Clean up.
+	os.Remove(installerImage)
+	os.Exit(code)
+}
+
+func TestInstallerImage(t *testing.T) {
+	// This test examines the installer image, making sure that the GPT and the
+	// ESP contents are in order.
+	image, err := diskfs.OpenWithMode(installerImage, diskfs.ReadOnly)
+	if err != nil {
+		t.Errorf("Couldn't open the installer image at %q: %s", installerImage, err.Error())
+	}
+	// Verify that GPT exists.
+	ti, err := image.GetPartitionTable()
+	if err != nil {
+		t.Fatalf("Couldn't read the installer image partition table: %s", err)
+	}
+	if ti.Type() != "gpt" {
+		t.Error("Couldn't verify that the installer image contains a GPT.")
+	}
+	// Check that the first partition is likely to be a valid ESP.
+	pi := ti.GetPartitions()
+	esp := (pi[0]).(*gpt.Partition)
+	if esp.Start == 0 || esp.End == 0 {
+		t.Error("The installer's ESP GPT entry looks off.")
+	}
+	// Verify that the image contains only one partition.
+	second := (pi[1]).(*gpt.Partition)
+	if second.Name != "" || second.Start != 0 || second.End != 0 {
+		t.Error("It appears the installer image contains more than one partition.")
+	}
+	// Verify the ESP contents.
+	if err := checkEspContents(image); err != nil {
+		t.Error(err.Error())
+	}
+}
+
+func TestNoBlockDevices(t *testing.T) {
+	ctx, ctxC := context.WithCancel(context.Background())
+	defer ctxC()
+
+	// No block devices are passed to QEMU aside from the install medium. Expect
+	// the installer to fail at the device probe stage rather than attempting to
+	// use the medium as the target device.
+	expectedOutput := "Couldn't find a suitable block device"
+	result, err := runQemuWithInstaller(ctx, nil, expectedOutput)
+	if err != nil {
+		t.Error(err.Error())
+	}
+	if !result {
+		t.Errorf("QEMU didn't produce the expected output %q", expectedOutput)
+	}
+}
+
+func TestBlockDeviceTooSmall(t *testing.T) {
+	ctx, ctxC := context.WithCancel(context.Background())
+	defer ctxC()
+
+	// Prepare the block device the installer will install to. This time the
+	// target device is too small to host a Metropolis installation.
+	imagePath, err := getStorage(64)
+	defer os.Remove(imagePath)
+	if err != nil {
+		t.Errorf(err.Error())
+	}
+
+	// Run QEMU. Expect the installer to fail with a predefined error string.
+	expectedOutput := "Couldn't find a suitable block device"
+	result, err := runQemuWithInstaller(ctx, qemuDriveParam(imagePath), expectedOutput)
+	if err != nil {
+		t.Error(err.Error())
+	}
+	if !result {
+		t.Errorf("QEMU didn't produce the expected output %q", expectedOutput)
+	}
+}
+
+func TestInstall(t *testing.T) {
+	ctx, ctxC := context.WithCancel(context.Background())
+	defer ctxC()
+
+	// Prepare the block device image the installer will install to.
+	// Needs enough storage for two 4096 MiB system partitions, a 384 MiB ESP
+	// and a 128 MiB data partition. In addition at the start and end we need
+	// 1MiB for GPT headers and alignment.
+	storagePath, err := getStorage(4096*2 + 384 + 128 + 2)
+	defer os.Remove(storagePath)
+	if err != nil {
+		t.Errorf(err.Error())
+	}
+
+	// Run QEMU. Expect the installer to succeed.
+	expectedOutput := "Installation completed"
+	result, err := runQemuWithInstaller(ctx, qemuDriveParam(storagePath), expectedOutput)
+	if err != nil {
+		t.Error(err.Error())
+	}
+	if !result {
+		t.Errorf("QEMU didn't produce the expected output %q", expectedOutput)
+	}
+
+	// Verify the resulting node image. Check whether the node GPT was created.
+	storage, err := diskfs.OpenWithMode(storagePath, diskfs.ReadOnly)
+	if err != nil {
+		t.Errorf("Couldn't open the resulting node image at %q: %s", storagePath, err.Error())
+	}
+	// Verify that GPT exists.
+	ti, err := storage.GetPartitionTable()
+	if err != nil {
+		t.Fatalf("Couldn't read the installer image partition table: %s", err)
+	}
+	if ti.Type() != "gpt" {
+		t.Error("Couldn't verify that the resulting node image contains a GPT.")
+	}
+	// Check that the first partition is likely to be a valid ESP.
+	pi := ti.GetPartitions()
+	esp := (pi[0]).(*gpt.Partition)
+	if esp.Name != osimage.ESPLabel || esp.Start == 0 || esp.End == 0 {
+		t.Error("The node's ESP GPT entry looks off.")
+	}
+	// Verify the system partition's GPT entry.
+	system := (pi[1]).(*gpt.Partition)
+	if system.Name != osimage.SystemALabel || system.Start == 0 || system.End == 0 {
+		t.Error("The node's system partition GPT entry looks off.")
+	}
+	// Verify the system partition's GPT entry.
+	systemB := (pi[2]).(*gpt.Partition)
+	if systemB.Name != osimage.SystemBLabel || systemB.Start == 0 || systemB.End == 0 {
+		t.Error("The node's system partition GPT entry looks off.")
+	}
+	// Verify the data partition's GPT entry.
+	data := (pi[3]).(*gpt.Partition)
+	if data.Name != osimage.DataLabel || data.Start == 0 || data.End == 0 {
+		t.Errorf("The node's data partition GPT entry looks off: %+v", data)
+	}
+	// Verify that there are no more partitions.
+	fourth := (pi[4]).(*gpt.Partition)
+	if fourth.Name != "" || fourth.Start != 0 || fourth.End != 0 {
+		t.Error("The resulting node image contains more partitions than expected.")
+	}
+	// Verify the ESP contents.
+	if err := checkEspContents(storage); err != nil {
+		t.Error(err.Error())
+	}
+	storage.File.Close()
+	// Run QEMU again. Expect TestOS to launch successfully.
+	expectedOutput = "_TESTOS_LAUNCH_SUCCESS_"
+	time.Sleep(time.Second)
+	result, err = runQemu(ctx, qemuDriveParam(storagePath), expectedOutput)
+	if err != nil {
+		t.Error(err.Error())
+	}
+	if !result {
+		t.Errorf("QEMU didn't produce the expected output %q", expectedOutput)
+	}
+}