copier: rsync с возобновлением, папка назначения, права 777

- Заменить ручное копирование на rsync --partial --append-verify
- Структура на диске: <mount>/<dest_folder>/<rel path from /media>
- dest_folder настраивается (default: media)
- Права на диске: --no-perms --chmod=ugo=rwx
- rsync добавлен в Dockerfile
- Режим "удалить": удаляет только dest_folder, а не весь диск

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

internal/copier/copier.go

@@ -4,8 +4,8 @@ import (
 	"context"
 	"errors"
 	"fmt"
-	"io"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"sync"
 
@@ -19,6 +19,7 @@ type Options struct {
 	DiskID         string
 	MountPath      string
 	MediaPath      string
+	DestFolder     string // subfolder on disk, default "media"
 	EnabledSources []string
 	ReserveFreeGB  float64
 	OverwriteMode  config.OverwriteMode
@@ -39,7 +40,6 @@ func New(tasks *task.Store) *Copier {
 	return &Copier{tasks: tasks}
 }
 
-// SetDB replaces the active disk database (called when a disk connects or disconnects).
 func (c *Copier) SetDB(d *db.DB) {
 	c.dbMu.Lock()
 	c.db = d
@@ -65,6 +65,10 @@ func (c *Copier) Start(ctx context.Context, opts Options) (string, error) {
 		return "", errors.New("no disk database available")
 	}
 
+	if opts.DestFolder == "" {
+		opts.DestFolder = "media"
+	}
+
 	t := c.tasks.Create("copy")
 	copyCtx, cancel := context.WithCancel(ctx)
 	c.cancel = cancel
@@ -98,9 +102,11 @@ func (c *Copier) run(ctx context.Context, taskID string, opts Options, database
 
 	setStatus(task.StatusRunning, "Подготовка…", 0)
 
+	destRoot := filepath.Join(opts.MountPath, opts.DestFolder)
+
 	if opts.OverwriteMode == config.OverwriteDelete {
 		setStatus(task.StatusRunning, "Удаление данных с диска…", 0)
-		if err := deleteOurData(opts.MountPath); err != nil {
+		if err := os.RemoveAll(destRoot); err != nil {
 			fail(err)
 			return
 		}
@@ -161,8 +167,10 @@ func (c *Copier) run(ctx context.Context, taskID string, opts Options, database
 		prog := int(float64(i+1) / float64(total) * 100)
 		setStatus(task.StatusRunning, msg, prog)
 
-		dstAbs := filepath.Join(opts.MountPath, f.relPath)
-		if err := copyFile(ctx, f.srcAbs, dstAbs); err != nil {
+		// destination mirrors source structure under destRoot
+		dstAbs := filepath.Join(destRoot, f.relPath)
+
+		if err := rsyncFile(ctx, f.srcAbs, dstAbs); err != nil {
 			if errors.Is(err, context.Canceled) {
 				c.tasks.Update(taskID, func(t *task.Task) {
 					t.Status = task.StatusCanceled
@@ -187,7 +195,7 @@ func (c *Copier) run(ctx context.Context, taskID string, opts Options, database
 
 type fileEntry struct {
 	srcAbs  string
-	relPath string
+	relPath string // relative to /media
 	size    int64
 }
 
@@ -217,64 +225,29 @@ func buildFileList(mediaPath string, sources []string, skip map[string]struct{})
 	return result, nil
 }
 
-func deleteOurData(mountPath string) error {
-	entries, err := os.ReadDir(mountPath)
-	if err != nil {
-		return err
-	}
-	for _, e := range entries {
-		if e.Name() == ".jukebox" {
-			continue
-		}
-		if err := os.RemoveAll(filepath.Join(mountPath, e.Name())); err != nil {
-			return err
-		}
-	}
-	return nil
-}
-
-func copyFile(ctx context.Context, src, dst string) error {
+// rsyncFile copies src to dst using rsync with resume support.
+// --partial keeps partial files on interruption.
+// --append-verify resumes partial transfers and verifies checksums.
+func rsyncFile(ctx context.Context, src, dst string) error {
 	if err := os.MkdirAll(filepath.Dir(dst), 0o755); err != nil {
 		return err
 	}
-	in, err := os.Open(src)
+	cmd := exec.CommandContext(ctx, "rsync",
+		"--partial",
+		"--append-verify",
+		"--times",
+		"--no-perms",
+		"--no-owner",
+		"--no-group",
+		"--chmod=ugo=rwx",
+		src, dst,
+	)
+	out, err := cmd.CombinedOutput()
 	if err != nil {
-		return err
-	}
-	defer in.Close()
-
-	tmp := dst + ".juketmp"
-	out, err := os.Create(tmp)
-	if err != nil {
-		return err
-	}
-
-	buf := make([]byte, 512*1024)
-	for {
-		select {
-		case <-ctx.Done():
-			out.Close()
-			os.Remove(tmp)
+		if ctx.Err() != nil {
 			return ctx.Err()
-		default:
-		}
-		n, readErr := in.Read(buf)
-		if n > 0 {
-			if _, werr := out.Write(buf[:n]); werr != nil {
-				out.Close()
-				os.Remove(tmp)
-				return werr
-			}
-		}
-		if errors.Is(readErr, io.EOF) {
-			break
-		}
-		if readErr != nil {
-			out.Close()
-			os.Remove(tmp)
-			return readErr
 		}
+		return fmt.Errorf("rsync: %w: %s", err, out)
 	}
-	out.Close()
-	return os.Rename(tmp, dst)
+	return nil
 }