Copilot suggestions fixed

app/server.go

@@ -2,7 +2,6 @@ package app
 
 import (
 	"context"
-	"fmt"
 	"fs/api"
 	"fs/auth"
 	"fs/logging"
@@ -85,7 +84,7 @@ func RunServer(ctx context.Context) error {
 
 	if err := handler.Start(ctx, addr); err != nil {
 		logger.Error("server_stopped_with_error", "error", err)
-		return fmt.Errorf("server start failed: %w", err)
+		return err
 	}
 	return nil
 }

cmd/admin_snapshot.go

@@ -390,7 +390,10 @@ func ensureDataPathOffline(dataPath string) error {
 		}
 		return err
 	}
-	db, err := bolt.Open(dbPath, 0o600, &bolt.Options{Timeout: 100 * time.Millisecond})
+	db, err := bolt.Open(dbPath, 0o600, &bolt.Options{
+		Timeout:  100 * time.Millisecond,
+		ReadOnly: true,
+	})
 	if err != nil {
 		return fmt.Errorf("data path appears in use (metadata.db locked): %w", err)
 	}

cmd/admin_snapshot_test.go

@@ -0,0 +1,240 @@
+package cmd
+
+import (
+	"archive/tar"
+	"bytes"
+	"compress/gzip"
+	"context"
+	"crypto/sha256"
+	"encoding/hex"
+	"encoding/json"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+
+	bolt "go.etcd.io/bbolt"
+)
+
+type snapshotArchiveEntry struct {
+	Path string
+	Data []byte
+}
+
+func TestInspectSnapshotArchiveRejectsUnsafePath(t *testing.T) {
+	t.Parallel()
+
+	archive := filepath.Join(t.TempDir(), "bad.tar.gz")
+	manifest := manifestForEntries([]snapshotArchiveEntry{
+		{Path: "metadata.db", Data: []byte("db")},
+	})
+	err := writeSnapshotArchiveForTest(archive, manifest, []snapshotArchiveEntry{
+		{Path: "../escape", Data: []byte("oops")},
+	}, true)
+	if err != nil {
+		t.Fatalf("write test archive: %v", err)
+	}
+
+	_, _, err = inspectSnapshotArchive(archive)
+	if err == nil || !strings.Contains(err.Error(), "unsafe archive path") {
+		t.Fatalf("expected unsafe archive path error, got %v", err)
+	}
+}
+
+func TestInspectSnapshotArchiveChecksumMismatch(t *testing.T) {
+	t.Parallel()
+
+	archive := filepath.Join(t.TempDir(), "mismatch.tar.gz")
+	manifest := manifestForEntries([]snapshotArchiveEntry{
+		{Path: "chunks/c1", Data: []byte("good")},
+	})
+	err := writeSnapshotArchiveForTest(archive, manifest, []snapshotArchiveEntry{
+		{Path: "chunks/c1", Data: []byte("bad")},
+	}, true)
+	if err != nil {
+		t.Fatalf("write test archive: %v", err)
+	}
+
+	_, _, err = inspectSnapshotArchive(archive)
+	if err == nil || !strings.Contains(err.Error(), "checksum mismatch") {
+		t.Fatalf("expected checksum mismatch error, got %v", err)
+	}
+}
+
+func TestInspectSnapshotArchiveMissingManifest(t *testing.T) {
+	t.Parallel()
+
+	archive := filepath.Join(t.TempDir(), "no-manifest.tar.gz")
+	err := writeSnapshotArchiveForTest(archive, nil, []snapshotArchiveEntry{
+		{Path: "chunks/c1", Data: []byte("x")},
+	}, false)
+	if err != nil {
+		t.Fatalf("write test archive: %v", err)
+	}
+
+	_, _, err = inspectSnapshotArchive(archive)
+	if err == nil || !strings.Contains(err.Error(), "manifest.json not found") {
+		t.Fatalf("expected missing manifest error, got %v", err)
+	}
+}
+
+func TestInspectSnapshotArchiveUnsupportedFormat(t *testing.T) {
+	t.Parallel()
+
+	archive := filepath.Join(t.TempDir(), "unsupported-format.tar.gz")
+	manifest := manifestForEntries([]snapshotArchiveEntry{
+		{Path: "chunks/c1", Data: []byte("x")},
+	})
+	manifest.FormatVersion = 99
+	err := writeSnapshotArchiveForTest(archive, manifest, []snapshotArchiveEntry{
+		{Path: "chunks/c1", Data: []byte("x")},
+	}, true)
+	if err != nil {
+		t.Fatalf("write test archive: %v", err)
+	}
+
+	_, _, err = inspectSnapshotArchive(archive)
+	if err == nil || !strings.Contains(err.Error(), "unsupported snapshot format version") {
+		t.Fatalf("expected unsupported format error, got %v", err)
+	}
+}
+
+func TestRestoreSnapshotArchiveDestinationBehavior(t *testing.T) {
+	t.Parallel()
+
+	root := t.TempDir()
+	archive := filepath.Join(root, "ok.tar.gz")
+	destination := filepath.Join(root, "dst")
+
+	entries := []snapshotArchiveEntry{
+		{Path: "metadata.db", Data: []byte("db-bytes")},
+		{Path: "chunks/c1", Data: []byte("chunk-1")},
+	}
+	manifest := manifestForEntries(entries)
+	if err := writeSnapshotArchiveForTest(archive, manifest, entries, true); err != nil {
+		t.Fatalf("write test archive: %v", err)
+	}
+
+	if err := os.MkdirAll(destination, 0o755); err != nil {
+		t.Fatalf("mkdir destination: %v", err)
+	}
+	if err := os.WriteFile(filepath.Join(destination, "old.txt"), []byte("old"), 0o600); err != nil {
+		t.Fatalf("seed destination: %v", err)
+	}
+
+	if _, err := restoreSnapshotArchive(context.Background(), archive, destination, false); err == nil || !strings.Contains(err.Error(), "not empty") {
+		t.Fatalf("expected non-empty destination error, got %v", err)
+	}
+
+	if _, err := restoreSnapshotArchive(context.Background(), archive, destination, true); err != nil {
+		t.Fatalf("restore with force: %v", err)
+	}
+
+	if _, err := os.Stat(filepath.Join(destination, "old.txt")); !os.IsNotExist(err) {
+		t.Fatalf("expected old file to be removed, stat err=%v", err)
+	}
+	got, err := os.ReadFile(filepath.Join(destination, "chunks/c1"))
+	if err != nil {
+		t.Fatalf("read restored chunk: %v", err)
+	}
+	if string(got) != "chunk-1" {
+		t.Fatalf("restored chunk mismatch: got %q", string(got))
+	}
+}
+
+func TestCreateSnapshotArchiveRejectsOutputInsideDataPath(t *testing.T) {
+	t.Parallel()
+
+	root := t.TempDir()
+	if err := os.MkdirAll(filepath.Join(root, "chunks"), 0o755); err != nil {
+		t.Fatalf("mkdir chunks: %v", err)
+	}
+	if err := createBoltDBForTest(filepath.Join(root, "metadata.db")); err != nil {
+		t.Fatalf("create metadata db: %v", err)
+	}
+	if err := os.WriteFile(filepath.Join(root, "chunks/c1"), []byte("x"), 0o600); err != nil {
+		t.Fatalf("write chunk: %v", err)
+	}
+
+	out := filepath.Join(root, "inside.tar.gz")
+	if _, err := createSnapshotArchive(context.Background(), root, out); err == nil || !strings.Contains(err.Error(), "cannot be inside") {
+		t.Fatalf("expected output-inside-data-path error, got %v", err)
+	}
+}
+
+func writeSnapshotArchiveForTest(path string, manifest *snapshotManifest, entries []snapshotArchiveEntry, includeManifest bool) error {
+	file, err := os.Create(path)
+	if err != nil {
+		return err
+	}
+	defer file.Close()
+
+	gzw := gzip.NewWriter(file)
+	defer gzw.Close()
+	tw := tar.NewWriter(gzw)
+	defer tw.Close()
+
+	if includeManifest {
+		raw, err := json.Marshal(manifest)
+		if err != nil {
+			return err
+		}
+		if err := writeTarEntry(tw, snapshotManifestPath, raw); err != nil {
+			return err
+		}
+	}
+	for _, entry := range entries {
+		if err := writeTarEntry(tw, entry.Path, entry.Data); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func writeTarEntry(tw *tar.Writer, name string, data []byte) error {
+	header := &tar.Header{
+		Name: name,
+		Mode: 0o600,
+		Size: int64(len(data)),
+	}
+	if err := tw.WriteHeader(header); err != nil {
+		return err
+	}
+	_, err := ioCopyBytes(tw, data)
+	return err
+}
+
+func manifestForEntries(entries []snapshotArchiveEntry) *snapshotManifest {
+	files := make([]snapshotFileEntry, 0, len(entries))
+	for _, entry := range entries {
+		sum := sha256.Sum256(entry.Data)
+		files = append(files, snapshotFileEntry{
+			Path:   filepath.ToSlash(filepath.Clean(entry.Path)),
+			Size:   int64(len(entry.Data)),
+			SHA256: hex.EncodeToString(sum[:]),
+		})
+	}
+	return &snapshotManifest{
+		FormatVersion: snapshotFormat,
+		CreatedAt:     "2026-03-11T00:00:00Z",
+		SourcePath:    "/tmp/source",
+		Files:         files,
+	}
+}
+
+func createBoltDBForTest(path string) error {
+	db, err := bolt.Open(path, 0o600, nil)
+	if err != nil {
+		return err
+	}
+	defer db.Close()
+	return db.Update(func(tx *bolt.Tx) error {
+		_, err := tx.CreateBucketIfNotExists([]byte("x"))
+		return err
+	})
+}
+
+func ioCopyBytes(w *tar.Writer, data []byte) (int64, error) {
+	n, err := bytes.NewReader(data).WriteTo(w)
+	return n, err
+}