vaultik/internal/vaultik/missing_destination_test.go

package vaultik_test

import (
	"bytes"
	"context"
	"io/fs"
	"os"
	"path/filepath"
	"strings"
	"sync"
	"testing"

	"github.com/spf13/afero"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
	"sneak.berlin/go/vaultik/internal/database"
	"sneak.berlin/go/vaultik/internal/log"
	"sneak.berlin/go/vaultik/internal/storage"
	"sneak.berlin/go/vaultik/internal/ui"
	"sneak.berlin/go/vaultik/internal/vaultik"
)

// These tests cover https://git.eeqj.de/sneak/vaultik/issues/220: a
// file:// destination whose directory is missing, such as a USB stick
// that is not plugged in, cannot be listed. It is not an empty store, so
// no command may conclude from it that the local snapshots are gone.

// newFileDestinationVaultik writes the fault source tree and returns a
// Vaultik that backs it up to a file:// destination at storeDir.
func newFileDestinationVaultik(
	ctx context.Context, t *testing.T, storeDir string,
) (*vaultik.Vaultik, *database.Repositories) {
	t.Helper()

	tempDir := t.TempDir()
	dataDir := filepath.Join(tempDir, "src")
	writeFaultSourceTree(t, afero.NewOsFs(), dataDir)

	return openFileDestinationVaultik(ctx, t, storeDir, dataDir,
		filepath.Join(tempDir, "index.sqlite"))
}

// openFileDestinationVaultik returns a Vaultik that backs up dataDir to a
// file:// destination at storeDir, with its local index at dbPath. The
// index is closed when the test ends.
func openFileDestinationVaultik(
	ctx context.Context, t *testing.T, storeDir, dataDir, dbPath string,
) (*vaultik.Vaultik, *database.Repositories) {
	t.Helper()

	store, err := storage.NewFileStorer(storeDir)
	require.NoError(t, err)

	db, err := database.New(ctx, dbPath)
	require.NoError(t, err)
	t.Cleanup(func() { _ = db.Close() })

	repos := database.NewRepositories(db)
	cfg := changedFileConfig(dataDir, dbPath)

	return newBackupVaultik(ctx, cfg, store, repos, db, afero.NewOsFs()), repos
}

// firstBackup is one backup of the snapshot named "first" to a file://
// destination. dir holds its source tree in src, its store in store and
// its closed local index in index/index.sqlite. The first test that
// needs it makes it, and TestMain removes it. Every test that copies it
// backs up the same source tree, so no test may change that tree.
//
//nolint:gochecknoglobals // made once and shared by the tests that copy it
var firstBackup struct {
	once  sync.Once
	dir   string
	ready bool
}

// TestMain removes firstBackup once every test has run.
func TestMain(m *testing.M) {
	code := m.Run()

	_ = os.RemoveAll(firstBackup.dir)

	os.Exit(code)
}

// makeFirstBackup writes the fault source tree and backs it up as the
// snapshot named "first", all in a new directory that it records in
// firstBackup.
func makeFirstBackup(ctx context.Context, t *testing.T) {
	t.Helper()

	dir, err := os.MkdirTemp("", "vaultik-first-backup-")
	require.NoError(t, err)

	firstBackup.dir = dir
	storeDir := filepath.Join(dir, "store")
	dataDir := filepath.Join(dir, "src")
	indexDir := filepath.Join(dir, "index")

	require.NoError(t, os.Mkdir(storeDir, 0o750))
	require.NoError(t, os.Mkdir(indexDir, 0o750))
	writeFaultSourceTree(t, afero.NewOsFs(), dataDir)

	v, _ := openFileDestinationVaultik(ctx, t, storeDir, dataDir,
		filepath.Join(indexDir, "index.sqlite"))
	require.NoError(t, backUp(v, "first"))
	require.NoError(t, v.DB.Close())

	firstBackup.ready = true
}

// backUpToFileDestination creates the directory storeDir, as a user must
// before the first backup, and returns a Vaultik whose file://
// destination there holds a backup of the snapshot named "first". The
// store and the local index are copies of firstBackup's, which is faster
// than backing up in every test. The returned Vaultik backs up a source
// tree shared with every other caller, so no test may change that tree.
// Everything the returned Vaultik prints after the backup goes to the
// returned buffer.
func backUpToFileDestination(
	ctx context.Context, t *testing.T, storeDir string,
) (*vaultik.Vaultik, *database.Repositories, *bytes.Buffer) {
	t.Helper()

	firstBackup.once.Do(func() { makeFirstBackup(ctx, t) })
	require.True(t, firstBackup.ready, "another test failed to make firstBackup")

	require.NoError(t, os.MkdirAll(storeDir, 0o750))
	require.NoError(t, os.CopyFS(storeDir,
		os.DirFS(filepath.Join(firstBackup.dir, "store"))))

	indexDir := t.TempDir()
	require.NoError(t, os.CopyFS(indexDir,
		os.DirFS(filepath.Join(firstBackup.dir, "index"))))

	v, repos := openFileDestinationVaultik(ctx, t, storeDir,
		filepath.Join(firstBackup.dir, "src"),
		filepath.Join(indexDir, "index.sqlite"))

	out := &bytes.Buffer{}
	v.Stdout = out
	v.UI = ui.NewWithColor(out, false)

	return v, repos, out
}

// backUpThenUnplug backs up to a file:// destination, then moves the
// destination directory away, as unplugging the volume it lives on would.
func backUpThenUnplug(
	ctx context.Context, t *testing.T,
) (*vaultik.Vaultik, *database.Repositories, *bytes.Buffer) {
	t.Helper()

	storeDir := filepath.Join(t.TempDir(), "usbstick")
	v, repos, out := backUpToFileDestination(ctx, t, storeDir)

	require.NoError(t, os.Rename(storeDir, storeDir+"-unplugged"))

	return v, repos, out
}

// TestBackupFailsWhenDestinationDirectoryMissing checks that a backup to
// a file:// destination whose directory does not exist fails before it
// records a snapshot, and does not create the directory.
func TestBackupFailsWhenDestinationDirectoryMissing(t *testing.T) {
	log.Initialize(log.Config{})
	t.Parallel()

	ctx := context.Background()
	volume := filepath.Join(t.TempDir(), "volume")
	v, repos := newFileDestinationVaultik(ctx, t, filepath.Join(volume, "backup"))

	err := backUp(v, "first")
	require.ErrorIs(t, err, fs.ErrNotExist)
	require.ErrorContains(t, err, "create it, or mount the volume it is on")

	_, err = os.Stat(volume)
	require.ErrorIs(t, err, fs.ErrNotExist,
		"the backup must not create the destination directory")

	snapshots, err := repos.Snapshots.ListRecent(ctx, listRecentTestLimit)
	require.NoError(t, err)
	assert.Empty(t, snapshots)
}

// TestListSnapshotsWarnsWhenDestinationMissing checks that snapshot list
// warns and shows the local index alone, without reporting the local
// snapshot as missing from the destination.
func TestListSnapshotsWarnsWhenDestinationMissing(t *testing.T) {
	log.Initialize(log.Config{})
	t.Parallel()

	ctx := context.Background()
	v, repos, out := backUpThenUnplug(ctx, t)
	id := localSnapshotID(ctx, t, repos, "first")

	require.NoError(t, v.ListSnapshots(false))

	assert.Contains(t, out.String(), "Could not list backup destination store")
	assert.Contains(t, out.String(), "Showing snapshots from the local index only.")
	assert.Contains(t, out.String(), id)
	assert.NotContains(t, out.String(), "not found in backup destination store")
}

// TestRemoveSnapshotWarnsWhenDestinationMissing checks that snapshot
// remove warns that the metadata could not be removed from the
// destination, instead of reporting that it was.
func TestRemoveSnapshotWarnsWhenDestinationMissing(t *testing.T) {
	log.Initialize(log.Config{})
	t.Parallel()

	ctx := context.Background()
	v, repos, out := backUpThenUnplug(ctx, t)

	result, err := v.RemoveSnapshot(localSnapshotID(ctx, t, repos, "first"),
		&vaultik.RemoveOptions{Force: true})
	require.NoError(t, err)

	assert.False(t, result.RemoteRemoved)
	assert.Contains(t, out.String(),
		"Could not remove snapshot metadata from remote")
	assert.NotContains(t, out.String(),
		"Removed snapshot metadata from remote storage")
}

// TestPruneKeepsLocalRecordsWhenDestinationMissing checks that prune
// fails on a destination it cannot list and deletes no local snapshot
// record.
func TestPruneKeepsLocalRecordsWhenDestinationMissing(t *testing.T) {
	log.Initialize(log.Config{})
	t.Parallel()

	ctx := context.Background()
	v, repos, _ := backUpThenUnplug(ctx, t)

	err := v.Prune(&vaultik.PruneOptions{Force: true})
	require.ErrorIs(t, err, fs.ErrNotExist)
	require.ErrorContains(t, err, "listing remote snapshots")

	snapshots, err := repos.Snapshots.ListRecent(ctx, listRecentTestLimit)
	require.NoError(t, err)
	assert.Len(t, snapshots, 1, "prune must delete no local snapshot record")
}

// TestPurgeSaysListingFailedOnceWhenDestinationMissing checks that
// snapshot purge fails on a destination it cannot list, with an error
// that says "listing remote snapshots" once.
func TestPurgeSaysListingFailedOnceWhenDestinationMissing(t *testing.T) {
	log.Initialize(log.Config{})
	t.Parallel()

	ctx := context.Background()
	v, _, _ := backUpThenUnplug(ctx, t)

	err := v.PurgeSnapshotsWithOptions(&vaultik.SnapshotPurgeOptions{
		KeepLatest: true,
		Force:      true,
	})
	require.ErrorIs(t, err, fs.ErrNotExist)
	assert.Equal(t, 1, strings.Count(err.Error(), "listing remote snapshots"),
		err.Error())
}

// TestNukeRemoteKeepsLocalIndexWhenDestinationMissing checks that remote
// nuke fails on a destination it cannot list, leaves the local index
// unchanged, and neither reports the destination empty nor advises
// running nuke again.
func TestNukeRemoteKeepsLocalIndexWhenDestinationMissing(t *testing.T) {
	log.Initialize(log.Config{})
	t.Parallel()

	ctx := context.Background()
	v, repos, out := backUpThenUnplug(ctx, t)

	filesBefore, err := repos.Files.ListAll(ctx)
	require.NoError(t, err)
	require.NotEmpty(t, filesBefore)

	blobsBefore, err := repos.Blobs.GetAll(ctx)
	require.NoError(t, err)
	require.NotEmpty(t, blobsBefore)

	err = v.NukeRemote(true)
	require.ErrorIs(t, err, fs.ErrNotExist)
	require.ErrorContains(t, err, "listing remote snapshots")
	assert.NotContains(t, out.String(), "now empty")
	assert.NotContains(t, out.String(), "vaultik remote nuke --force")

	snapshots, err := repos.Snapshots.ListRecent(ctx, listRecentTestLimit)
	require.NoError(t, err)
	assert.Len(t, snapshots, 1, "nuke must delete no local snapshot record")

	files, err := repos.Files.ListAll(ctx)
	require.NoError(t, err)
	assert.Len(t, files, len(filesBefore), "nuke must delete no local file record")

	blobs, err := repos.Blobs.GetAll(ctx)
	require.NoError(t, err)
	assert.Len(t, blobs, len(blobsBefore), "nuke must delete no local blob record")
}