Exit as interrupted when Ctrl-C lands during a local index write (closes #301)

Once the run's context is cancelled, database/sql rolls an open
transaction back itself, so the rollback in WithTx returned
sql.ErrTxDone. WithTx treated any rollback error as fatal and called
os.Exit(1): an interrupted backup printed "FATAL: failed to rollback
transaction", exited 1 instead of 130 and skipped its deferred cleanup.

WithTx now ignores sql.ErrTxDone from the rollback and returns the
body's error. A rollback that really fails is returned together with
the body's error instead of ending the process; on a panic it is
dropped and the panic carries on. The tests make the rollback really
fail by running ROLLBACK inside the body.

Model: opus-5-5

internal/database/repositories.go

@@ -3,6 +3,7 @@ package database
 import (
 	"context"
 	"database/sql"
+	"errors"
 	"fmt"
 )
 
@@ -60,22 +61,24 @@ func (r *Repositories) WithTx(ctx context.Context, fn TxFunc) error {
 
 	defer func() {
 		if p := recover(); p != nil {
-			rollbackErr := tx.Rollback()
-			if rollbackErr != nil {
-				Fatalf("failed to rollback transaction: %v", rollbackErr)
-			}
+			// The panic is the failure to report, so a rollback error
+			// is dropped.
+			_ = tx.Rollback()
 
 			panic(p)
-		} else if err != nil {
-			rollbackErr := tx.Rollback()
-			if rollbackErr != nil {
-				Fatalf("failed to rollback transaction: %v", rollbackErr)
-			}
 		}
 	}()
 
 	err = fn(ctx, tx)
 	if err != nil {
+		// Once ctx is cancelled, database/sql rolls the transaction
+		// back itself and Rollback returns sql.ErrTxDone.
+		rollbackErr := tx.Rollback()
+		if rollbackErr != nil && !errors.Is(rollbackErr, sql.ErrTxDone) {
+			return fmt.Errorf("%w; rolling back transaction: %w",
+				err, rollbackErr)
+		}
+
 		return err
 	}
 

internal/database/repositories_test.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"database/sql"
 	"errors"
+	"strings"
 	"testing"
 	"time"
 
@@ -235,6 +236,121 @@ func TestRepositoriesTransactionRollback(t *testing.T) {
 	}
 }
 
+// When the context is cancelled during the body, database/sql rolls the
+// transaction back itself, so WithTx's own rollback finds it already
+// done. WithTx must still return the body's error.
+func TestRepositoriesTransactionContextCancelled(t *testing.T) {
+	t.Parallel()
+
+	db, cleanup := setupTestDB(t)
+	defer cleanup()
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	repos := database.NewRepositories(db)
+
+	err := repos.WithTx(ctx, func(ctx context.Context, tx *sql.Tx) error {
+		file := &database.File{
+			Path:  "/test/cancelled_file.txt",
+			MTime: time.Now().Truncate(time.Second),
+			Size:  1024,
+			Mode:  0644,
+			UID:   1000,
+			GID:   1000,
+		}
+
+		err := repos.Files.Create(ctx, tx, file)
+		if err != nil {
+			return err
+		}
+
+		cancel()
+
+		// database/sql rolls back from a goroutine of its own; wait
+		// until it has, so the test does not depend on that race.
+		for {
+			_, err = tx.ExecContext(context.WithoutCancel(ctx), "SELECT 1")
+			if errors.Is(err, sql.ErrTxDone) {
+				return ctx.Err()
+			}
+
+			time.Sleep(time.Millisecond)
+		}
+	})
+	if !errors.Is(err, context.Canceled) {
+		t.Fatalf("expected context.Canceled, got: %v", err)
+	}
+
+	file, err := repos.Files.GetByPath(
+		context.Background(), "/test/cancelled_file.txt",
+	)
+	if err != nil {
+		t.Fatalf("error checking for file: %v", err)
+	}
+
+	if file != nil {
+		t.Error("file should not exist after the cancelled transaction")
+	}
+}
+
+// A body that ends the transaction itself with ROLLBACK makes WithTx's
+// own rollback fail. WithTx must return that failure together with the
+// body's error.
+func TestRepositoriesTransactionRollbackFails(t *testing.T) {
+	t.Parallel()
+
+	db, cleanup := setupTestDB(t)
+	defer cleanup()
+
+	ctx := context.Background()
+	repos := database.NewRepositories(db)
+
+	err := repos.WithTx(ctx, func(ctx context.Context, tx *sql.Tx) error {
+		_, err := tx.ExecContext(ctx, "ROLLBACK")
+		if err != nil {
+			return err
+		}
+
+		return errIntentionalRollback
+	})
+	if !errors.Is(err, errIntentionalRollback) {
+		t.Fatalf("expected the body's error, got: %v", err)
+	}
+
+	if !strings.Contains(err.Error(), "rolling back transaction") {
+		t.Errorf("expected the failed rollback in the error, got: %v", err)
+	}
+}
+
+// When the body ends the transaction itself with ROLLBACK and then
+// panics, WithTx's own rollback fails; the panic must still reach the
+// caller.
+func TestRepositoriesTransactionPanicRollbackFails(t *testing.T) {
+	t.Parallel()
+
+	db, cleanup := setupTestDB(t)
+	defer cleanup()
+
+	ctx := context.Background()
+	repos := database.NewRepositories(db)
+
+	defer func() {
+		if recover() == nil {
+			t.Error("expected the body's panic to reach the caller")
+		}
+	}()
+
+	_ = repos.WithTx(ctx, func(ctx context.Context, tx *sql.Tx) error {
+		_, err := tx.ExecContext(ctx, "ROLLBACK")
+		if err != nil {
+			return err
+		}
+
+		panic(errIntentionalRollback)
+	})
+}
+
 func TestRepositoriesReadTransaction(t *testing.T) {
 	t.Parallel()
 

internal/vaultik/restore.go

@@ -309,22 +309,11 @@ func (v *Vaultik) restoreAllFiles(
 		return nil, err
 	}
 
-	plan, unplanned, err := newRestorePlan(
-		v.ctx, repos, files, chunkToBlobMap, blobIDToHash)
+	plan, err := newRestorePlan(v.ctx, repos, files, chunkToBlobMap, blobIDToHash)
 	if err != nil {
 		return nil, fmt.Errorf("building restore plan: %w", err)
 	}
 
-	// Ranging over files rather than the map reports them in a stable order.
-	for _, file := range files {
-		if planErr, ok := unplanned[file.ID]; ok {
-			err = v.handleRestoreFileError(plan, opts, result, file, file.ID, planErr)
-			if err != nil {
-				return nil, err
-			}
-		}
-	}
-
 	filesByID, totalBytesExpected := indexRestoreFiles(files)
 
 	v.UI.Beginf("Restoring %s files (%s) to %s.",

internal/vaultik/restore_malformed_db_test.go

@@ -61,8 +61,8 @@ func craftedFile(
 }
 
 // TestRestoreShortChunkHashInNoBlob proves a file whose short chunk hash
-// has no blob_chunks row is left out of the restore plan with an error,
-// and fails the chunk write with an error.
+// has no blob_chunks row fails restore planning and the chunk write with
+// an error.
 func TestRestoreShortChunkHashInNoBlob(t *testing.T) {
 	t.Parallel()
 
@@ -77,11 +77,9 @@ func TestRestoreShortChunkHashInNoBlob(t *testing.T) {
 	chunkToBlobMap, err := v.buildChunkToBlobMap(ctx, repos)
 	require.NoError(t, err)
 
-	plan, unplanned, err := newRestorePlan(ctx, repos, []*database.File{file},
+	_, err = newRestorePlan(ctx, repos, []*database.File{file},
 		chunkToBlobMap, map[string]string{})
-	require.NoError(t, err)
-	require.ErrorIs(t, unplanned[file.ID], errPlanChunkMissing)
-	require.False(t, plan.hasPending())
+	require.ErrorIs(t, err, errPlanChunkMissing)
 
 	fileChunks, err := repos.FileChunks.GetByFileID(ctx, file.ID)
 	require.NoError(t, err)

internal/vaultik/restore_plan.go

@@ -41,25 +41,20 @@ type restorePlan struct {
 
 // newRestorePlan builds the file→blob index for the given files. Files
 // whose chunks reference no blobs (symlinks, directories) start in the
-// ready queue immediately. A file with a chunk that no blob holds cannot
-// be restored: it is left out of the plan and returned, by ID, with the
-// reason.
+// ready queue immediately.
 func newRestorePlan(
 	ctx context.Context,
 	repos *database.Repositories,
 	files []*database.File,
 	chunkToBlobMap map[string]*database.BlobChunk,
 	blobIDToHash map[string]string,
-) (*restorePlan, map[types.FileID]error, error) {
+) (*restorePlan, error) {
 	p := &restorePlan{
 		fileBlobs: make(map[types.FileID]map[string]struct{}, len(files)),
 		blobFiles: make(map[string]map[types.FileID]struct{}),
 		ready:     make([]types.FileID, 0, len(files)),
 		cached:    make(map[string]struct{}),
 	}
-	unplanned := make(map[types.FileID]error)
-
-nextFile:
 	for _, f := range files {
 		if f.IsSymlink() || f.Mode&uint32(os.ModeDir) != 0 {
 			// No chunks to fetch — restore can run immediately.
@@ -71,7 +66,7 @@ nextFile:
 
 		fileChunks, err := repos.FileChunks.GetByFileID(ctx, f.ID)
 		if err != nil {
-			return nil, nil, fmt.Errorf("planning %s: %w", f.Path, err)
+			return nil, fmt.Errorf("planning %s: %w", f.Path, err)
 		}
 
 		blobs := make(map[string]struct{})
@@ -79,18 +74,14 @@ nextFile:
 		for _, fc := range fileChunks {
 			bc, ok := chunkToBlobMap[fc.ChunkHash.String()]
 			if !ok {
-				unplanned[f.ID] = fmt.Errorf("%w: %s",
-					errPlanChunkMissing, shortHash(fc.ChunkHash.String()))
-
-				continue nextFile
+				return nil, fmt.Errorf("planning %s: %w: %s",
+					f.Path, errPlanChunkMissing, shortHash(fc.ChunkHash.String()))
 			}
 
 			hash, ok := blobIDToHash[bc.BlobID.String()]
 			if !ok {
-				unplanned[f.ID] = fmt.Errorf("%w: %s",
-					errPlanBlobIDMissing, bc.BlobID)
-
-				continue nextFile
+				return nil, fmt.Errorf("planning %s: %w: %s",
+					f.Path, errPlanBlobIDMissing, bc.BlobID)
 			}
 
 			blobs[hash] = struct{}{}
@@ -112,7 +103,7 @@ nextFile:
 		}
 	}
 
-	return p, unplanned, nil
+	return p, nil
 }
 
 // markBlobCached records that the named blob is now resident in the

internal/vaultik/restore_skip_errors_test.go

@@ -28,8 +28,7 @@ const (
 )
 
 // missingBlobBackup is a snapshot of single-chunk files spread over two
-// blobs, with one of those blobs lost: deleted from the store, or missing
-// from the snapshot metadata.
+// blobs, with one of those blobs deleted from the store.
 type missingBlobBackup struct {
 	fs         afero.Fs
 	cfg        *config.Config
@@ -38,39 +37,20 @@ type missingBlobBackup struct {
 	restoreDir string
 	// files holds the original content by source path.
 	files map[string][]byte
-	// lost holds the source paths whose chunk is in the lost blob.
+	// lost holds the source paths whose chunk is in the deleted blob.
 	lost map[string]bool
 }
 
 // TestRestoreSkipErrorsSkipsFilesOfMissingBlob restores with SkipErrors
-// after one blob of a two-blob snapshot was deleted from the store.
+// after one blob of a two-blob snapshot was deleted. Every file stored in
+// that blob must be reported as failed and left absent, every other file
+// must be restored intact, and Restore must still return an error.
 func TestRestoreSkipErrorsSkipsFilesOfMissingBlob(t *testing.T) {
 	log.Initialize(log.Config{})
 	t.Parallel()
 
 	ctx := context.Background()
-	assertRestoreSkipsLostFiles(ctx, t, backupThenDeleteOneBlob(ctx, t))
-}
-
-// TestRestoreSkipErrorsSkipsFilesWithChunkInNoBlob restores with
-// SkipErrors a snapshot whose metadata lists chunks that no blob holds, as
-// earlier backup defects left behind.
-func TestRestoreSkipErrorsSkipsFilesWithChunkInNoBlob(t *testing.T) {
-	log.Initialize(log.Config{})
-	t.Parallel()
-
-	ctx := context.Background()
-	assertRestoreSkipsLostFiles(ctx, t, backupThenDropOneBlobFromMetadata(ctx, t))
-}
-
-// assertRestoreSkipsLostFiles restores backup with SkipErrors. Every file
-// stored in the lost blob must be reported as failed and left absent,
-// every other file must be restored intact, and Restore must still return
-// an error.
-func assertRestoreSkipsLostFiles(
-	ctx context.Context, t *testing.T, backup *missingBlobBackup,
-) {
-	t.Helper()
+	backup := backupThenDeleteOneBlob(ctx, t)
 
 	var out bytes.Buffer
 
@@ -92,14 +72,14 @@ func assertRestoreSkipsLostFiles(
 
 		if backup.lost[path] {
 			assert.Containsf(t, out.String(), path,
-				"%s needs the lost blob and must be reported", path)
+				"%s needs the deleted blob and must be reported", path)
 			assert.NoFileExists(t, restored)
 
 			continue
 		}
 
 		got, err := afero.ReadFile(backup.fs, restored)
-		require.NoErrorf(t, err, "%s does not need the lost blob", path)
+		require.NoErrorf(t, err, "%s does not need the deleted blob", path)
 		assert.Equalf(t, content, got, "%s restored with wrong content", path)
 	}
 }
@@ -123,30 +103,6 @@ func TestRestoreMissingBlobAbortsWithoutSkipErrors(t *testing.T) {
 	require.ErrorIs(t, err, storage.ErrNotFound)
 }
 
-// TestRestoreChunkInNoBlobAbortsWithoutSkipErrors checks that a chunk held
-// by no blob still ends the restore, before any file is written, when
-// SkipErrors is not set.
-func TestRestoreChunkInNoBlobAbortsWithoutSkipErrors(t *testing.T) {
-	log.Initialize(log.Config{})
-	t.Parallel()
-
-	ctx := context.Background()
-	backup := backupThenDropOneBlobFromMetadata(ctx, t)
-
-	v := newReaderVaultik(ctx, backup.cfg, backup.storer, nil, backup.fs)
-
-	err := v.Restore(&vaultik.RestoreOptions{
-		SnapshotID: backup.snapshotID,
-		TargetDir:  backup.restoreDir,
-	})
-
-	require.ErrorContains(t, err, "chunk missing from blob map")
-
-	for path := range backup.files {
-		assert.NoFileExists(t, filepath.Join(backup.restoreDir, path))
-	}
-}
-
 // backupThenDeleteOneBlob backs up missingBlobFileCount single-chunk
 // files, then deletes from the store the blob holding the first of them.
 func backupThenDeleteOneBlob(
@@ -154,54 +110,6 @@ func backupThenDeleteOneBlob(
 ) *missingBlobBackup {
 	t.Helper()
 
-	backup, db, lostBlob := backupSingleChunkFiles(ctx, t)
-	require.NoError(t, db.Close())
-
-	require.NoError(t, backup.storer.Delete(ctx, fmt.Sprintf(
-		"blobs/%s/%s/%s", lostBlob[:2], lostBlob[2:4], lostBlob)))
-
-	return backup
-}
-
-// backupThenDropOneBlobFromMetadata backs up missingBlobFileCount
-// single-chunk files, then removes the blob holding the first of them from
-// the snapshot and exports the snapshot metadata again. The exported
-// metadata then lists chunks that no blob holds.
-func backupThenDropOneBlobFromMetadata(
-	ctx context.Context, t *testing.T,
-) *missingBlobBackup {
-	t.Helper()
-
-	backup, db, lostBlob := backupSingleChunkFiles(ctx, t)
-
-	// The uploads row refers to the blob row, so it would keep the export
-	// from deleting it.
-	for _, query := range []string{
-		"DELETE FROM snapshot_blobs WHERE blob_hash = ?",
-		"DELETE FROM uploads WHERE blob_hash = ?",
-	} {
-		_, err := db.Conn().ExecContext(ctx, query, lostBlob)
-		require.NoError(t, err)
-	}
-
-	sm := newFaultSnapshotManager(
-		backup.fs, backup.storer, backup.cfg, database.NewRepositories(db))
-	require.NoError(t,
-		sm.ExportSnapshotMetadata(ctx, db.Path(), backup.snapshotID))
-	require.NoError(t, db.Close())
-
-	return backup
-}
-
-// backupSingleChunkFiles backs up missingBlobFileCount single-chunk files.
-// It returns the backup, with lost naming the files stored in the same
-// blob as the first of them, the still open local index, and the hash of
-// that blob.
-func backupSingleChunkFiles(
-	ctx context.Context, t *testing.T,
-) (*missingBlobBackup, *database.DB, string) {
-	t.Helper()
-
 	fs := afero.NewOsFs()
 	tempDir := t.TempDir()
 	dataDir := filepath.Join(tempDir, "src")
@@ -235,11 +143,16 @@ func backupSingleChunkFiles(
 		blobOfFile[path] = blobHashOfSingleChunkFile(ctx, t, repos, path)
 	}
 
-	lostBlob := blobOfFile[filepath.Join(dataDir, "file-00.bin")]
+	require.NoError(t, db.Close())
+
+	deleted := blobOfFile[filepath.Join(dataDir, "file-00.bin")]
+	require.NoError(t, storer.Delete(ctx, fmt.Sprintf(
+		"blobs/%s/%s/%s", deleted[:2], deleted[2:4], deleted)))
+
 	lost := make(map[string]bool)
 
 	for path, hash := range blobOfFile {
-		if hash == lostBlob {
+		if hash == deleted {
 			lost[path] = true
 		}
 	}
@@ -255,7 +168,7 @@ func backupSingleChunkFiles(
 		restoreDir: filepath.Join(tempDir, "restored"),
 		files:      files,
 		lost:       lost,
-	}, db, lostBlob
+	}
 }
 
 // blobHashOfSingleChunkFile returns the hash of the blob holding the one