[#469] List multipart uploads streaming

Signed-off-by: Nikita Zinkevich <n.zinkevich@yadro.com>

api/cache/listmultipart.go

@@ -0,0 +1,109 @@
+package cache
+
+import (
+	"fmt"
+	"time"
+
+	"git.frostfs.info/TrueCloudLab/frostfs-s3-gw/api/data"
+	"git.frostfs.info/TrueCloudLab/frostfs-s3-gw/internal/logs"
+	cid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/container/id"
+	"github.com/bluele/gcache"
+	"go.uber.org/zap"
+)
+
+type (
+	// ListMultipartSessionCache contains cache for list multiparts session (during pagination).
+	ListMultipartSessionCache struct {
+		cache  gcache.Cache
+		logger *zap.Logger
+	}
+
+	// ListMultipartSessionKey is a key to find a ListMultipartSessionCache's entry.
+	ListMultipartSessionKey struct {
+		cid      cid.ID
+		prefix   string
+		marker   string
+		uploadID string
+	}
+)
+
+const (
+	// DefaultListMultipartSessionCacheLifetime is a default lifetime of entries in cache of ListMultipartUploads.
+	DefaultListMultipartSessionCacheLifetime = time.Second * 60
+	// DefaultListMultipartSessionCacheSize is a default size of cache of ListMultipartUploads.
+	DefaultListMultipartSessionCacheSize = 100
+)
+
+// DefaultListMultipartSessionConfig returns new default cache expiration values.
+func DefaultListMultipartSessionConfig(logger *zap.Logger) *Config {
+	return &Config{
+		Size:     DefaultListMultipartSessionCacheSize,
+		Lifetime: DefaultListMultipartSessionCacheLifetime,
+		Logger:   logger,
+	}
+}
+
+func (k *ListMultipartSessionKey) String() string {
+	return k.cid.EncodeToString() + k.prefix + k.marker + k.uploadID
+}
+
+// NewListMultipartSessionCache is a constructor which creates an object of ListObjectsCache with the given lifetime of entries.
+func NewListMultipartSessionCache(config *Config) *ListMultipartSessionCache {
+	gc := gcache.New(config.Size).LRU().Expiration(config.Lifetime).EvictedFunc(func(_ interface{}, val interface{}) {
+		session, ok := val.(*data.ListMultipartSession)
+		if !ok {
+			config.Logger.Warn(logs.InvalidCacheEntryType, zap.String("actual", fmt.Sprintf("%T", val)),
+				zap.String("expected", fmt.Sprintf("%T", session)))
+		}
+
+		if !session.Acquired.Load() {
+			session.Cancel()
+		}
+	}).Build()
+	return &ListMultipartSessionCache{cache: gc, logger: config.Logger}
+}
+
+// GetListMultipartSession returns a session of ListMultipartUploads request.
+func (l *ListMultipartSessionCache) GetListMultipartSession(key ListMultipartSessionKey) *data.ListMultipartSession {
+	entry, err := l.cache.Get(key)
+	if err != nil {
+		return nil
+	}
+
+	result, ok := entry.(*data.ListMultipartSession)
+	if !ok {
+		l.logger.Warn(logs.InvalidCacheEntryType, zap.String("actual", fmt.Sprintf("%T", entry)),
+			zap.String("expected", fmt.Sprintf("%T", result)))
+		return nil
+	}
+
+	return result
+}
+
+// PutListMultipartSession puts a ListMultipartUploads session info to cache.
+func (l *ListMultipartSessionCache) PutListMultipartSession(key ListMultipartSessionKey, session *data.ListMultipartSession) error {
+	s := l.GetListMultipartSession(key)
+	if s != nil && s != session {
+		if !s.Acquired.Load() {
+			s.Cancel()
+		}
+	}
+	return l.cache.Set(key, session)
+}
+
+// DeleteListMultipartSession removes key from cache.
+func (l *ListMultipartSessionCache) DeleteListMultipartSession(key ListMultipartSessionKey) {
+	l.cache.Remove(key)
+}
+
+// CreateListMultipartSessionCacheKey returns ListMultipartSessionKey with the given CID, prefix, marker and uploadID.
+func CreateListMultipartSessionCacheKey(cnr cid.ID, prefix, marker, uploadID string) ListMultipartSessionKey {
+	p := ListMultipartSessionKey{
+		cid:      cnr,
+		prefix:   prefix,
+		marker:   marker,
+		uploadID: uploadID,
+	}
+
+	return p
+}

api/data/listsession.go

@@ -9,11 +9,25 @@ type VersionsStream interface {
 	Next(ctx context.Context) (*NodeVersion, error)
 }
 
-type ListSession struct {
+type CommonSession struct {
-	Next     []*ExtendedNodeVersion
-	Stream   VersionsStream
-	NamesMap map[string]struct{}
 	Context  context.Context
 	Cancel   context.CancelFunc
 	Acquired atomic.Bool
 }
+
+type ListSession struct {
+	CommonSession
+	Next     []*ExtendedNodeVersion
+	Stream   VersionsStream
+	NamesMap map[string]struct{}
+}
+
+type MultipartInfoStream interface {
+	Next(ctx context.Context) (*MultipartInfo, error)
+}
+
+type ListMultipartSession struct {
+	CommonSession
+	Next   *MultipartInfo
+	Stream MultipartInfoStream
+}

api/data/tree.go

@@ -207,3 +207,9 @@ func (l LockInfo) UntilDate() string {
 func (l LockInfo) IsCompliance() bool {
 	return l.isCompliance
 }
+
+type MultipartStreamParams struct {
+	Prefix         string
+	KeyMarker      string
+	UploadIDMarker string
+}

api/handler/handlers_test.go

@@ -244,6 +244,7 @@ func getMinCacheConfig(logger *zap.Logger) *layer.CachesConfig {
 		Buckets:       minCacheCfg,
 		System:        minCacheCfg,
 		AccessControl: minCacheCfg,
+		MultipartList: minCacheCfg,
 		NetworkInfo:   &cache.NetworkInfoCacheConfig{Lifetime: minCacheCfg.Lifetime},
 	}
 }

api/handler/multipart_upload.go

@@ -513,7 +513,7 @@ func (h *handler) ListMultipartUploadsHandler(w http.ResponseWriter, r *http.Req
 
 	if maxUploadsStr != "" {
 		val, err := strconv.Atoi(maxUploadsStr)
-		if err != nil || val < 1 || val > 1000 {
+		if err != nil || val < 1 || val > maxObjectList {
 			h.logAndSendError(ctx, w, "invalid maxUploads", reqInfo, errors.GetAPIError(errors.ErrInvalidMaxUploads))
 			return
 		}

api/handler/multipart_upload_test.go

@@ -294,6 +294,58 @@ func TestListMultipartUploads(t *testing.T) {
 			require.Equal(t, uploadInfo3.UploadID, listUploads.Uploads[0].UploadID)
 		})
 	})
+
+	t.Run("check next markers", func(t *testing.T) {
+		t.Run("check both next-key-marker and next-upload-id-marker", func(t *testing.T) {
+			listUploads := listMultipartUploads(hc, bktName, "", "", "", "", 1)
+			require.True(t, listUploads.IsTruncated)
+			require.Len(t, listUploads.Uploads, 1)
+			require.Equal(t, uploadInfo1.Key, listUploads.NextKeyMarker)
+			require.Equal(t, uploadInfo1.UploadID, listUploads.NextUploadIDMarker)
+			require.Equal(t, uploadInfo1.UploadID, listUploads.Uploads[0].UploadID)
+			require.Equal(t, uploadInfo1.Key, listUploads.Uploads[0].Key)
+
+			listUploads = listMultipartUploads(hc, bktName, "", "", listUploads.NextUploadIDMarker, listUploads.NextKeyMarker, 1)
+			require.True(t, listUploads.IsTruncated)
+			require.Len(t, listUploads.Uploads, 1)
+			require.Equal(t, uploadInfo2.Key, listUploads.NextKeyMarker)
+			require.Equal(t, uploadInfo2.UploadID, listUploads.NextUploadIDMarker)
+			require.Equal(t, uploadInfo2.UploadID, listUploads.Uploads[0].UploadID)
+			require.Equal(t, uploadInfo2.Key, listUploads.Uploads[0].Key)
+
+			listUploads = listMultipartUploads(hc, bktName, "", "", listUploads.NextUploadIDMarker, listUploads.NextKeyMarker, 1)
+			require.False(t, listUploads.IsTruncated)
+			require.Len(t, listUploads.Uploads, 1)
+			require.Empty(t, listUploads.NextUploadIDMarker)
+			require.Empty(t, listUploads.NextKeyMarker)
+			require.Equal(t, uploadInfo3.UploadID, listUploads.Uploads[0].UploadID)
+		})
+
+		t.Run("check only next-key-marker", func(t *testing.T) {
+			listUploads := listMultipartUploads(hc, bktName, "", "", "", "", 1)
+			require.True(t, listUploads.IsTruncated)
+			require.Len(t, listUploads.Uploads, 1)
+			require.Equal(t, uploadInfo1.Key, listUploads.NextKeyMarker)
+			require.Equal(t, uploadInfo1.UploadID, listUploads.NextUploadIDMarker)
+			require.Equal(t, uploadInfo1.UploadID, listUploads.Uploads[0].UploadID)
+			require.Equal(t, uploadInfo1.Key, listUploads.Uploads[0].Key)
+
+			listUploads = listMultipartUploads(hc, bktName, "", "", "", listUploads.NextKeyMarker, 1)
+			require.True(t, listUploads.IsTruncated)
+			require.Len(t, listUploads.Uploads, 1)
+			require.Equal(t, uploadInfo2.Key, listUploads.NextKeyMarker)
+			require.Equal(t, uploadInfo2.UploadID, listUploads.NextUploadIDMarker)
+			require.Equal(t, uploadInfo2.UploadID, listUploads.Uploads[0].UploadID)
+			require.Equal(t, uploadInfo2.Key, listUploads.Uploads[0].Key)
+
+			listUploads = listMultipartUploads(hc, bktName, "", "", "", listUploads.NextKeyMarker, 1)
+			require.False(t, listUploads.IsTruncated)
+			require.Len(t, listUploads.Uploads, 1)
+			require.Empty(t, listUploads.NextUploadIDMarker)
+			require.Empty(t, listUploads.NextKeyMarker)
+			require.Equal(t, uploadInfo3.UploadID, listUploads.Uploads[0].UploadID)
+		})
+	})
 }
 
 func TestMultipartUploadSize(t *testing.T) {

api/layer/cache.go

@@ -12,15 +12,16 @@ import (
 )
 
 type Cache struct {
-	logger           *zap.Logger
+	logger                *zap.Logger
-	listsCache       *cache.ObjectsListCache
+	listsCache            *cache.ObjectsListCache
-	sessionListCache *cache.ListSessionCache
+	sessionListCache      *cache.ListSessionCache
-	objCache         *cache.ObjectsCache
+	objCache              *cache.ObjectsCache
-	namesCache       *cache.ObjectsNameCache
+	namesCache            *cache.ObjectsNameCache
-	bucketCache      *cache.BucketCache
+	bucketCache           *cache.BucketCache
-	systemCache      *cache.SystemCache
+	systemCache           *cache.SystemCache
-	accessCache      *cache.AccessControlCache
+	accessCache           *cache.AccessControlCache
-	networkInfoCache *cache.NetworkInfoCache
+	networkInfoCache      *cache.NetworkInfoCache
+	sessionMultipartCache *cache.ListMultipartSessionCache
 }
 
 // CachesConfig contains params for caches.
@@ -33,6 +34,7 @@ type CachesConfig struct {
 	Buckets       *cache.Config
 	System        *cache.Config
 	AccessControl *cache.Config
+	MultipartList *cache.Config
 	NetworkInfo   *cache.NetworkInfoCacheConfig
 }
 
@@ -48,20 +50,22 @@ func DefaultCachesConfigs(logger *zap.Logger) *CachesConfig {
 		System:        cache.DefaultSystemConfig(logger),
 		AccessControl: cache.DefaultAccessControlConfig(logger),
 		NetworkInfo:   cache.DefaultNetworkInfoConfig(logger),
+		MultipartList: cache.DefaultListMultipartSessionConfig(logger),
 	}
 }
 
 func NewCache(cfg *CachesConfig) *Cache {
 	return &Cache{
-		logger:           cfg.Logger,
+		logger:                cfg.Logger,
-		listsCache:       cache.NewObjectsListCache(cfg.ObjectsList),
+		listsCache:            cache.NewObjectsListCache(cfg.ObjectsList),
-		sessionListCache: cache.NewListSessionCache(cfg.SessionList),
+		sessionListCache:      cache.NewListSessionCache(cfg.SessionList),
-		objCache:         cache.New(cfg.Objects),
+		objCache:              cache.New(cfg.Objects),
-		namesCache:       cache.NewObjectsNameCache(cfg.Names),
+		namesCache:            cache.NewObjectsNameCache(cfg.Names),
-		bucketCache:      cache.NewBucketCache(cfg.Buckets),
+		bucketCache:           cache.NewBucketCache(cfg.Buckets),
-		systemCache:      cache.NewSystemCache(cfg.System),
+		systemCache:           cache.NewSystemCache(cfg.System),
-		accessCache:      cache.NewAccessControlCache(cfg.AccessControl),
+		accessCache:           cache.NewAccessControlCache(cfg.AccessControl),
-		networkInfoCache: cache.NewNetworkInfoCache(cfg.NetworkInfo),
+		networkInfoCache:      cache.NewNetworkInfoCache(cfg.NetworkInfo),
+		sessionMultipartCache: cache.NewListMultipartSessionCache(cfg.MultipartList),
 	}
 }
 
@@ -161,6 +165,14 @@ func (c *Cache) GetListSession(owner user.ID, key cache.ListSessionKey) *data.Li
 	return c.sessionListCache.GetListSession(key)
 }
 
+func (c *Cache) GetListMultipartSession(owner user.ID, key cache.ListMultipartSessionKey) *data.ListMultipartSession {
+	if !c.accessCache.Get(owner, key.String()) {
+		return nil
+	}
+
+	return c.sessionMultipartCache.GetListMultipartSession(key)
+}
+
 func (c *Cache) PutListSession(owner user.ID, key cache.ListSessionKey, session *data.ListSession) {
 	if err := c.sessionListCache.PutListSession(key, session); err != nil {
 		c.logger.Warn(logs.CouldntCacheListSession, zap.Error(err))
@@ -176,6 +188,21 @@ func (c *Cache) DeleteListSession(owner user.ID, key cache.ListSessionKey) {
 	c.accessCache.Delete(owner, key.String())
 }
 
+func (c *Cache) PutListMultipartSession(owner user.ID, key cache.ListMultipartSessionKey, session *data.ListMultipartSession) {
+	if err := c.sessionMultipartCache.PutListMultipartSession(key, session); err != nil {
+		c.logger.Warn(logs.CouldntCacheListMultipartSession, zap.Error(err))
+	}
+
+	if err := c.accessCache.Put(owner, key.String()); err != nil {
+		c.logger.Warn(logs.CouldntCacheAccessControlOperation, zap.Error(err))
+	}
+}
+
+func (c *Cache) DeleteListMultipartSession(owner user.ID, key cache.ListMultipartSessionKey) {
+	c.sessionMultipartCache.DeleteListMultipartSession(key)
+	c.accessCache.Delete(owner, key.String())
+}
+
 func (c *Cache) GetTagging(owner user.ID, key string) map[string]string {
 	if !c.accessCache.Get(owner, key) {
 		return nil

api/layer/listing.go

@@ -79,7 +79,8 @@ type (
 		Prefix    string
 		MaxKeys   int
 		Marker    string
-		Bookmark  string
+		// Bookmark contains Marker or ContinuationToken and is used for pagination and as part of a cache key for list session.
+		Bookmark string
 	}
 
 	commonLatestVersionsListingParams struct {
@@ -193,11 +194,10 @@ func (n *Layer) getLatestObjectsVersions(ctx context.Context, p commonLatestVers
 		return nil, nil, nil
 	}
 
-	session, err := n.getListLatestVersionsSession(ctx, p)
+	session, err := n.getListVersionsSession(ctx, p.commonVersionsListingParams, true)
 	if err != nil {
 		return nil, nil, err
 	}
-
 	generator, errorCh := nodesGeneratorStream(ctx, p.commonVersionsListingParams, session)
 	objOutCh, err := n.initWorkerPool(ctx, 2, p.commonVersionsListingParams, generator)
 	if err != nil {
@@ -230,7 +230,7 @@ func (n *Layer) getAllObjectsVersions(ctx context.Context, p commonVersionsListi
 		return nil, false, nil
 	}
 
-	session, err := n.getListAllVersionsSession(ctx, p)
+	session, err := n.getListVersionsSession(ctx, p, false)
 	if err != nil {
 		return nil, false, err
 	}
@@ -301,48 +301,31 @@ func formVersionsListRow(objects []*data.ExtendedNodeVersion, rowStartIndex int,
 	}
 }
 
-func (n *Layer) getListLatestVersionsSession(ctx context.Context, p commonLatestVersionsListingParams) (*data.ListSession, error) {
+func (n *Layer) getListVersionsSession(ctx context.Context, p commonVersionsListingParams, latestOnly bool) (session *data.ListSession, err error) {
-	return n.getListVersionsSession(ctx, p.commonVersionsListingParams, true)
-}
-
-func (n *Layer) getListAllVersionsSession(ctx context.Context, p commonVersionsListingParams) (*data.ListSession, error) {
-	return n.getListVersionsSession(ctx, p, false)
-}
-
-func (n *Layer) getListVersionsSession(ctx context.Context, p commonVersionsListingParams, latestOnly bool) (*data.ListSession, error) {
 	owner := n.BearerOwner(ctx)
 
 	cacheKey := cache.CreateListSessionCacheKey(p.BktInfo.CID, p.Prefix, p.Bookmark)
-	session := n.cache.GetListSession(owner, cacheKey)
+	session = n.cache.GetListSession(owner, cacheKey)
-	if session == nil {
+	if session == nil || session.Acquired.Swap(true) {
-		return n.initNewVersionsByPrefixSession(ctx, p, latestOnly)
+		session = n.newSession(ctx)
+		session.Stream, err = n.treeService.InitVersionsByPrefixStream(session.Context, p.BktInfo, p.Prefix, latestOnly)
+		return session, err
 	}
 
-	if session.Acquired.Swap(true) {
-		return n.initNewVersionsByPrefixSession(ctx, p, latestOnly)
-	}
-
-	// after reading next object from stream in session
-	// the current cache value already doesn't match with next token in cache key
 	n.cache.DeleteListSession(owner, cacheKey)
-
 	return session, nil
 }
 
-func (n *Layer) initNewVersionsByPrefixSession(ctx context.Context, p commonVersionsListingParams, latestOnly bool) (session *data.ListSession, err error) {
+func (n *Layer) newSession(ctx context.Context) *data.ListSession {
-	session = &data.ListSession{NamesMap: make(map[string]struct{})}
+	session := &data.ListSession{NamesMap: make(map[string]struct{})}
 	session.Context, session.Cancel = context.WithCancel(context.Background())
 
+	// save access box data for next requests
 	if bd, err := middleware.GetBoxData(ctx); err == nil {
 		session.Context = middleware.SetBox(session.Context, &middleware.Box{AccessBox: bd})
 	}
 
-	session.Stream, err = n.treeService.InitVersionsByPrefixStream(session.Context, p.BktInfo, p.Prefix, latestOnly)
+	return session
-	if err != nil {
-		return nil, err
-	}
-
-	return session, nil
 }
 
 func (n *Layer) putListLatestVersionsSession(ctx context.Context, p commonLatestVersionsListingParams, session *data.ListSession, allObjects []*data.ExtendedNodeVersion) {

api/layer/multipart_upload.go

@@ -2,6 +2,7 @@ package layer
 
 import (
 	"bytes"
+	"cmp"
 	"context"
 	"crypto/md5"
 	"encoding/base64"
@@ -10,17 +11,20 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"slices"
 	"sort"
 	"strconv"
 	"strings"
 	"time"
 
 	"git.frostfs.info/TrueCloudLab/frostfs-s3-gw/api/auth"
+	"git.frostfs.info/TrueCloudLab/frostfs-s3-gw/api/cache"
 	"git.frostfs.info/TrueCloudLab/frostfs-s3-gw/api/data"
 	apierr "git.frostfs.info/TrueCloudLab/frostfs-s3-gw/api/errors"
 	"git.frostfs.info/TrueCloudLab/frostfs-s3-gw/api/layer/encryption"
 	"git.frostfs.info/TrueCloudLab/frostfs-s3-gw/api/layer/frostfs"
 	"git.frostfs.info/TrueCloudLab/frostfs-s3-gw/api/layer/tree"
+	"git.frostfs.info/TrueCloudLab/frostfs-s3-gw/api/middleware"
 	"git.frostfs.info/TrueCloudLab/frostfs-s3-gw/internal/logs"
 	oid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object/id"
 	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/user"
@@ -499,47 +503,60 @@ func (n *Layer) ListMultipartUploads(ctx context.Context, p *ListMultipartUpload
 		return &result, nil
 	}
 
-	multipartInfos, err := n.treeService.GetMultipartUploadsByPrefix(ctx, p.Bkt, p.Prefix)
+	session, err := n.getListMultipartUploadsSession(ctx, p)
 	if err != nil {
 		return nil, err
 	}
 
-	uploads := make([]*UploadInfo, 0, len(multipartInfos))
+	uploads := make([]*UploadInfo, 0, p.MaxUploads)
 	uniqDirs := make(map[string]struct{})
+	uploadsCount := 0
+	if session.Next != nil {
+		uploads = append(uploads, uploadInfoFromMultipartInfo(session.Next, p.Prefix, p.Delimiter))
+		uploadsCount++
+	}
 
-	for _, multipartInfo := range multipartInfos {
+	info := session.Next
-		info := uploadInfoFromMultipartInfo(multipartInfo, p.Prefix, p.Delimiter)
+	for uploadsCount < p.MaxUploads {
-		if info != nil {
+		info, err = session.Stream.Next(ctx)
-			if info.IsDir {
+		if err != nil {
-				if _, ok := uniqDirs[info.Key]; ok {
+			if err == io.EOF {
+				break
+			}
+			n.reqLogger(ctx).Warn(logs.CouldNotGetMultipartUploadInfo, zap.Error(err))
+			continue
+		}
+		upload := uploadInfoFromMultipartInfo(info, p.Prefix, p.Delimiter)
+		if upload != nil {
+			if upload.IsDir {
+				if _, ok := uniqDirs[upload.Key]; ok {
 					continue
 				}
-				uniqDirs[info.Key] = struct{}{}
+				uniqDirs[upload.Key] = struct{}{}
 			}
-			uploads = append(uploads, info)
+			uploads = append(uploads, upload)
+			uploadsCount++
 		}
 	}
 
-	sort.Slice(uploads, func(i, j int) bool {
+	isTruncated := true
-		if uploads[i].Key == uploads[j].Key {
+	next, err := session.Stream.Next(ctx)
-			return uploads[i].UploadID < uploads[j].UploadID
+	if err != nil {
-		}
+		if err == io.EOF {
-		return uploads[i].Key < uploads[j].Key
+			isTruncated = false
-	})
-
-	if p.KeyMarker != "" {
-		if p.UploadIDMarker != "" {
-			uploads = trimAfterUploadIDAndKey(p.KeyMarker, p.UploadIDMarker, uploads)
 		} else {
-			uploads = trimAfterUploadKey(p.KeyMarker, uploads)
+			return nil, err
 		}
 	}
 
-	if len(uploads) > p.MaxUploads {
+	if isTruncated && info != nil {
+		// put to session redundant multipart upload which we read to check for EOF
+		session.Next = next
 		result.IsTruncated = true
-		uploads = uploads[:p.MaxUploads]
+		result.NextUploadIDMarker = info.UploadID
-		result.NextUploadIDMarker = uploads[len(uploads)-1].UploadID
+		result.NextKeyMarker = info.Key
-		result.NextKeyMarker = uploads[len(uploads)-1].Key
+		cacheKey := cache.CreateListMultipartSessionCacheKey(p.Bkt.CID, p.Prefix, info.Key, info.UploadID)
+		n.putListMultipartUploadsSession(ctx, session, cacheKey)
 	}
 
 	for _, ov := range uploads {
@@ -550,9 +567,62 @@ func (n *Layer) ListMultipartUploads(ctx context.Context, p *ListMultipartUpload
 		}
 	}
 
+	slices.SortFunc(result.Uploads, func(a, b *UploadInfo) int {
+		keyCmp := cmp.Compare(a.Key, b.Key)
+		if keyCmp == 0 {
+			return cmp.Compare(a.UploadID, b.UploadID)
+		}
+
+		return keyCmp
+	})
+
 	return &result, nil
 }
 
+func (n *Layer) putListMultipartUploadsSession(ctx context.Context, session *data.ListMultipartSession, cacheKey cache.ListMultipartSessionKey) {
+	session.Acquired.Store(false)
+	n.cache.PutListMultipartSession(n.BearerOwner(ctx), cacheKey, session)
+}
+
+func (n *Layer) getListMultipartUploadsSession(ctx context.Context, p *ListMultipartUploadsParams) (session *data.ListMultipartSession, err error) {
+	owner := n.BearerOwner(ctx)
+	cacheKey := cache.CreateListMultipartSessionCacheKey(p.Bkt.CID, p.Prefix, p.KeyMarker, p.UploadIDMarker)
+	session = n.cache.GetListMultipartSession(owner, cacheKey)
+	if session == nil || session.Acquired.Swap(true) {
+		session = newListMultipartSession(ctx, session)
+		params := data.MultipartStreamParams{
+			Prefix:         p.Prefix,
+			KeyMarker:      p.KeyMarker,
+			UploadIDMarker: p.UploadIDMarker,
+		}
+		session.Stream, err = n.treeService.GetMultipartUploadsByPrefix(session.Context, p.Bkt, params)
+		if err != nil {
+			return nil, err
+		}
+	}
+	// if after reading next object from stream in session the current cache value already
+	// doesn't match with next token in cache key
+	n.cache.DeleteListMultipartSession(owner, cacheKey)
+
+	return session, nil
+}
+
+func newListMultipartSession(ctx context.Context, session *data.ListMultipartSession) *data.ListMultipartSession {
+	reqCtx, cancel := context.WithCancel(context.Background())
+	session = &data.ListMultipartSession{
+		CommonSession: data.CommonSession{
+			Context: reqCtx,
+			Cancel:  cancel,
+		},
+	}
+
+	// save access box data for next requests
+	if bd, err := middleware.GetBoxData(ctx); err == nil {
+		session.Context = middleware.SetBox(session.Context, &middleware.Box{AccessBox: bd})
+	}
+	return session
+}
+
 func (n *Layer) AbortMultipartUpload(ctx context.Context, p *UploadInfoParams) error {
 	multipartInfo, parts, err := n.getUploadParts(ctx, p)
 	if err != nil {

api/layer/tree/tree_service.go

@@ -53,7 +53,7 @@ type Service interface {
 
 	CreateMultipartUpload(ctx context.Context, bktInfo *data.BucketInfo, info *data.MultipartInfo) error
 	DeleteMultipartUpload(ctx context.Context, bktInfo *data.BucketInfo, info *data.MultipartInfo) error
-	GetMultipartUploadsByPrefix(ctx context.Context, bktInfo *data.BucketInfo, prefix string) ([]*data.MultipartInfo, error)
+	GetMultipartUploadsByPrefix(ctx context.Context, bktInfo *data.BucketInfo, params data.MultipartStreamParams) (data.MultipartInfoStream, error)
 	GetMultipartUpload(ctx context.Context, bktInfo *data.BucketInfo, objectName, uploadID string) (*data.MultipartInfo, error)
 
 	// AddPart puts a node to a system tree as a child of appropriate multipart upload

api/layer/tree_mock.go

@@ -328,7 +328,7 @@ func (t *TreeServiceMock) CreateMultipartUpload(_ context.Context, bktInfo *data
 	return nil
 }
 
-func (t *TreeServiceMock) GetMultipartUploadsByPrefix(context.Context, *data.BucketInfo, string) ([]*data.MultipartInfo, error) {
+func (t *TreeServiceMock) GetMultipartUploadsByPrefix(context.Context, *data.BucketInfo, data.MultipartStreamParams) (data.MultipartInfoStream, error) {
 	panic("implement me")
 }
 

cmd/s3-gw/app.go

@@ -1000,6 +1000,8 @@ func getCacheOptions(v *viper.Viper, l *zap.Logger) *layer.CachesConfig {
 	cacheCfg.AccessControl.Size = fetchCacheSize(v, l, cfgAccessControlCacheSize, cacheCfg.AccessControl.Size)
 
 	cacheCfg.NetworkInfo.Lifetime = fetchCacheLifetime(v, l, cfgNetworkInfoCacheLifetime, cacheCfg.NetworkInfo.Lifetime)
+	cacheCfg.MultipartList.Lifetime = fetchCacheLifetime(v, l, cfgMultipartListCacheLifetime, cacheCfg.MultipartList.Lifetime)
+	cacheCfg.MultipartList.Size = fetchCacheSize(v, l, cfgMultipartListCacheSize, cacheCfg.MultipartList.Size)
 
 	return cacheCfg
 }

cmd/s3-gw/app_settings.go

@@ -141,6 +141,8 @@ const ( // Settings.
 	cfgFrostfsIDCacheLifetime     = "cache.frostfsid.lifetime"
 	cfgFrostfsIDCacheSize         = "cache.frostfsid.size"
 	cfgNetworkInfoCacheLifetime   = "cache.network_info.lifetime"
+	cfgMultipartListCacheLifetime = "cache.multipart_list_session.lifetime"
+	cfgMultipartListCacheSize     = "cache.multipart_list_session.size"
 
 	cfgAccessBoxCacheRemovingCheckInterval = "cache.accessbox.removing_check_interval"
 

docs/configuration.md

@@ -426,6 +426,9 @@ cache:
   list_session:
     lifetime: 1m
     size: 100
+  multipart_list_session:
+     lifetime: 1m
+     size: 10000
   names:
     lifetime: 1m
     size: 1000
@@ -452,19 +455,20 @@ cache:
     lifetime: 1m
 ```
 
-| Parameter       | Type                                            | Default value                     | Description                                                    |
+| Parameter                | Type                                            | Default value                     | Description                                                    |
-|-----------------|-------------------------------------------------|-----------------------------------|----------------------------------------------------------------|
+|--------------------------|-------------------------------------------------|-----------------------------------|----------------------------------------------------------------|
-| `objects`       | [Cache config](#cache-subsection)               | `lifetime: 5m`<br>`size: 1000000` | Cache for objects (FrostFS headers).                           |
+| `objects`                | [Cache config](#cache-subsection)               | `lifetime: 5m`<br>`size: 1000000` | Cache for objects (FrostFS headers).                           |
-| `list`          | [Cache config](#cache-subsection)               | `lifetime: 60s`<br>`size: 100000` | Cache which keeps lists of objects in buckets.                 |
+| `list`                   | [Cache config](#cache-subsection)               | `lifetime: 60s`<br>`size: 100000` | Cache which keeps lists of objects in buckets.                 |
-| `list_session`  | [Cache config](#cache-subsection)               | `lifetime: 60s`<br>`size: 100`    | Cache which keeps listing session.                             |
+| `list_session`           | [Cache config](#cache-subsection)               | `lifetime: 60s`<br>`size: 100`    | Cache which keeps listing session.                             |
-| `names`         | [Cache config](#cache-subsection)               | `lifetime: 60s`<br>`size: 10000`  | Cache which contains mapping of nice name to object addresses. |
+| `multipart_list_session` | [Cache config](#cache-subsection)               | `lifetime: 60s`<br>`size: 100`    | Cache which keeps listing of multipart uploads.                |
-| `buckets`       | [Cache config](#cache-subsection)               | `lifetime: 60s`<br>`size: 1000`   | Cache which contains mapping of bucket name to bucket info.    |
+| `names`                  | [Cache config](#cache-subsection)               | `lifetime: 60s`<br>`size: 10000`  | Cache which contains mapping of nice name to object addresses. |
-| `system`        | [Cache config](#cache-subsection)               | `lifetime: 5m`<br>`size: 10000`   | Cache for system objects in a bucket: bucket settings etc.     |
+| `buckets`                | [Cache config](#cache-subsection)               | `lifetime: 60s`<br>`size: 1000`   | Cache which contains mapping of bucket name to bucket info.    |
-| `accessbox`     | [Accessbox cache config](#accessbox-subsection) | `lifetime: 10m`<br>`size: 100`    | Cache which stores access box with tokens by its address.      |
+| `system`                 | [Cache config](#cache-subsection)               | `lifetime: 5m`<br>`size: 10000`   | Cache for system objects in a bucket: bucket settings etc.     |
-| `accesscontrol` | [Cache config](#cache-subsection)               | `lifetime: 1m`<br>`size: 100000`  | Cache which stores owner to cache operation mapping.           |
+| `accessbox`              | [Accessbox cache config](#accessbox-subsection) | `lifetime: 10m`<br>`size: 100`    | Cache which stores access box with tokens by its address.      |
-| `morph_policy`  | [Cache config](#cache-subsection)               | `lifetime: 1m`<br>`size: 10000`   | Cache which stores list of policy chains.                      |
+| `accesscontrol`          | [Cache config](#cache-subsection)               | `lifetime: 1m`<br>`size: 100000`  | Cache which stores owner to cache operation mapping.           |
-| `frostfsid`     | [Cache config](#cache-subsection)               | `lifetime: 1m`<br>`size: 10000`   | Cache which stores FrostfsID subject info.                     |
+| `morph_policy`           | [Cache config](#cache-subsection)               | `lifetime: 1m`<br>`size: 10000`   | Cache which stores list of policy chains.                      |
-| `network_info`  | [Cache config](#cache-subsection)               | `lifetime: 1m`                    | Cache which stores network info.                               |
+| `frostfsid`              | [Cache config](#cache-subsection)               | `lifetime: 1m`<br>`size: 10000`   | Cache which stores FrostfsID subject info.                     |
+| `network_info`           | [Cache config](#cache-subsection)               | `lifetime: 1m`                    | Cache which stores network info.                               |
 
 #### `cache` subsection
 

internal/logs/logs.go

@@ -8,6 +8,8 @@ const (
 	UpdateAccessCredObjectIntoFrostFS                    = "update access cred object into FrostFS"                                                            // Info in ../../authmate/authmate.go
 	MetricsAreDisabled                                   = "metrics are disabled"                                                                              // Warn in ../../metrics/app.go
 	FoundMoreThanOneUnversionedNode                      = "found more than one unversioned node"                                                              // Debug in ../../pkg/service/tree/tree.go
+	CouldNotParseTreeNode                                = "could not parse tree node"                                                                         // Error in ../../pkg/service/tree/tree.go
+	CouldNotFormFilePath                                 = "could not form file path"                                                                          // Error in ../../pkg/service/tree/tree.go
 	ServiceIsRunning                                     = "service is running"                                                                                // Info in ../../cmd/s3-gw/service.go
 	ServiceCouldntStartOnConfiguredPort                  = "service couldn't start on configured port"                                                         // Warn in ../../cmd/s3-gw/service.go
 	ServiceHasntStartedSinceItsDisabled                  = "service hasn't started since it's disabled"                                                        // Info in ../../cmd/s3-gw/service.go
@@ -67,6 +69,7 @@ const (
 	CouldNotListUserContainers                           = "could not list user containers"                                                                    // Error in ../../api/layer/container.go
 	CouldNotFetchContainerInfo                           = "could not fetch container info"                                                                    // Error in ../../api/layer/container.go
 	MismatchedObjEncryptionInfo                          = "mismatched obj encryptionInfo"                                                                     // Warn in ../../api/layer/multipart_upload.go
+	CouldNotGetMultipartUploadInfo                       = "could not get multipart upload info"                                                               // Warn in ../../api/layer/multipart_upload.go
 	UploadPart                                           = "upload part"                                                                                       // Debug in ../../api/layer/multipart_upload.go
 	CouldntDeleteOldPartObject                           = "couldn't delete old part object"                                                                   // Error in ../../api/layer/multipart_upload.go
 	CouldNotPutCompletedObject                           = "could not put a completed object (multipart upload)"                                               // Error in ../../api/layer/multipart_upload.go
@@ -89,6 +92,7 @@ const (
 	CouldntPutObjAddressToNameCache                      = "couldn't put obj address to name cache"                                                            // Warn in ../../api/layer/cache.go
 	CouldntCacheListOfObjects                            = "couldn't cache list of objects"                                                                    // Warn in ../../api/layer/cache.go
 	CouldntCacheListSession                              = "couldn't cache list session"                                                                       // Warn in ../../api/layer/cache.go
+	CouldntCacheListMultipartSession                     = "couldn't cache list multipart session"                                                             // Warn in ../../api/layer/cache.go
 	CouldntCacheTags                                     = "couldn't cache tags"                                                                               // Error in ../../api/layer/cache.go
 	CouldntCacheLockInfo                                 = "couldn't cache lock info"                                                                          // Error in ../../api/layer/cache.go
 	CouldntCacheBucketSettings                           = "couldn't cache bucket settings"                                                                    // Warn in ../../api/layer/cache.go

pkg/service/tree/tree.go

@@ -84,7 +84,9 @@ var (
 	// ErrGatewayTimeout is returned from ServiceClient service in case of timeout error.
 	ErrGatewayTimeout = frostfs.ErrGatewayTimeout
 
-	errNodeDoesntContainFileName = fmt.Errorf("node doesn't contain FileName")
+	errNodeDoesntContainFileName = errors.New("node doesn't contain FileName")
+
+	errParentPathNotFound = errors.New("couldn't get parent path")
 )
 
 const (
@@ -1061,7 +1063,7 @@ func (s *VersionsByPrefixStreamImpl) parseNodeResponse(node NodeResponse) (res *
 
 	var filepath string
 	if !s.intermediateRootID.Equal(trNode.ID) {
-		if filepath, err = formFilePath(node, fileName, s.namesMap); err != nil {
+		if filepath, err = formFilePath(trNode, fileName, s.namesMap); err != nil {
 			return nil, false, fmt.Errorf("invalid node order: %w", err)
 		}
 	} else {
@@ -1165,58 +1167,18 @@ func (c *Tree) getPrefixNodeID(ctx context.Context, bktInfo *data.BucketInfo, tr
 	return intermediateNodes, nil
 }
 
-func (c *Tree) getSubTreeByPrefix(ctx context.Context, bktInfo *data.BucketInfo, treeID, prefix string, latestOnly bool) ([]NodeResponse, string, error) {
+func (c *Tree) getSubTreeByPrefixStream(ctx context.Context, bktInfo *data.BucketInfo, treeID, prefix string) (SubTreeStream, []uint64, error) {
-	rootID, tailPrefix, err := c.determinePrefixNode(ctx, bktInfo, treeID, prefix)
+	rootID, _, err := c.determinePrefixNode(ctx, bktInfo, treeID, prefix)
 	if err != nil {
 		if errors.Is(err, tree.ErrNodeNotFound) {
-			return nil, "", nil
+			return nil, nil, nil
 		}
-		return nil, "", err
+		return nil, nil, err
 	}
 
-	subTree, err := c.service.GetSubTree(ctx, bktInfo, treeID, rootID, 2, false)
+	stream, err := c.service.GetSubTreeStream(ctx, bktInfo, treeID, rootID, 2)
-	if err != nil {
-		if errors.Is(err, tree.ErrNodeNotFound) {
-			return nil, "", nil
-		}
-		return nil, "", err
-	}
 
-	nodesMap := make(map[string][]NodeResponse, len(subTree))
+	return stream, rootID, err
-	for _, node := range subTree {
-		if MultiID(rootID).Equal(node.GetNodeID()) {
-			continue
-		}
-
-		fileName := getFilename(node)
-		if !strings.HasPrefix(fileName, tailPrefix) {
-			continue
-		}
-
-		nodes := nodesMap[fileName]
-
-		// Add all nodes if flag latestOnly is false.
-		// Add all intermediate nodes
-		// and only latest leaf (object) nodes. To do this store and replace last leaf (object) node in nodes[0]
-		if len(nodes) == 0 {
-			nodes = []NodeResponse{node}
-		} else if !latestOnly || isIntermediate(node) {
-			nodes = append(nodes, node)
-		} else if isIntermediate(nodes[0]) {
-			nodes = append([]NodeResponse{node}, nodes...)
-		} else if getMaxTimestamp(node) > getMaxTimestamp(nodes[0]) {
-			nodes[0] = node
-		}
-
-		nodesMap[fileName] = nodes
-	}
-
-	result := make([]NodeResponse, 0, len(subTree))
-	for _, nodes := range nodesMap {
-		result = append(result, nodes...)
-	}
-
-	return result, strings.TrimSuffix(prefix, tailPrefix), nil
 }
 
 func getFilename(node NodeResponse) string {
@@ -1237,20 +1199,19 @@ func isIntermediate(node NodeResponse) bool {
 	return node.GetMeta()[0].GetKey() == FileNameKey
 }
 
-func formFilePath(node NodeResponse, fileName string, namesMap map[uint64]string) (string, error) {
+func formFilePath(node *treeNode, fileName string, namesMap map[uint64]string) (string, error) {
-	var filepath string
+	var filePath string
 
-	for i, id := range node.GetParentID() {
+	for i, id := range node.ParentID {
 		parentPath, ok := namesMap[id]
 		if !ok {
-			return "", fmt.Errorf("couldn't get parent path")
+			return "", errParentPathNotFound
 		}
-
+		filePath = parentPath + separator + fileName
-		filepath = parentPath + separator + fileName
+		namesMap[node.ID[i]] = filePath
-		namesMap[node.GetNodeID()[i]] = filepath
 	}
 
-	return filepath, nil
+	return filePath, nil
 }
 
 func parseTreeNode(node NodeResponse) (*treeNode, string, error) {
@@ -1267,10 +1228,6 @@ func parseTreeNode(node NodeResponse) (*treeNode, string, error) {
 	return tNode, fileName, nil
 }
 
-func formLatestNodeKey(parentID uint64, fileName string) string {
-	return strconv.FormatUint(parentID, 10) + "." + fileName
-}
-
 func (c *Tree) GetUnversioned(ctx context.Context, bktInfo *data.BucketInfo, filepath string) (*data.NodeVersion, error) {
 	return c.getUnversioned(ctx, bktInfo, versionTree, filepath)
 }
@@ -1313,84 +1270,122 @@ func (c *Tree) CreateMultipartUpload(ctx context.Context, bktInfo *data.BucketIn
 	return err
 }
 
-func (c *Tree) GetMultipartUploadsByPrefix(ctx context.Context, bktInfo *data.BucketInfo, prefix string) ([]*data.MultipartInfo, error) {
+type multipartInfoStream struct {
-	subTreeNodes, headPrefix, err := c.getSubTreeByPrefix(ctx, bktInfo, systemTree, prefix, false)
+	log       *zap.Logger
-	if err != nil {
+	nodePaths map[uint64]string
-		return nil, err
+	rootID    []uint64
-	}
+	// childStream stream of children nodes of prefix node.
-
+	childStream SubTreeStream
-	var result []*data.MultipartInfo
+	// currentStream stream of children's nodes with max depth.
-	for _, node := range subTreeNodes {
+	currentStream SubTreeStream
-		multipartUploads, err := c.getSubTreeMultipartUploads(ctx, bktInfo, node.GetNodeID(), headPrefix)
+	treeService   ServiceClient
-		if err != nil {
+	bktInfo       *data.BucketInfo
-			return nil, err
+	uploadID      string
-		}
+	keyMarker     string
-		result = append(result, multipartUploads...)
+	pathPrefix    string
-	}
-
-	return result, nil
 }
 
-func (c *Tree) getSubTreeMultipartUploads(ctx context.Context, bktInfo *data.BucketInfo, nodeID []uint64, parentFilePath string) ([]*data.MultipartInfo, error) {
+func (m *multipartInfoStream) Next(ctx context.Context) (*data.MultipartInfo, error) {
-	// sorting in getSubTree leads to skipping nodes that doesn't have FileName attribute
+	var tNode *treeNode
-	// so when we are only interested in multipart nodes, we can set this flag
+	var fileName, filePath string
-	// (despite we sort multiparts in above layer anyway)
+
-	// to skip its children (parts) that don't have FileName
+	if m.currentStream == nil {
-	subTree, err := c.service.GetSubTree(ctx, bktInfo, systemTree, nodeID, maxGetSubTreeDepth, true)
+		var err error
+		if m.currentStream, err = m.openNewStream(ctx); err != nil {
+			return nil, err
+		}
+	}
+	for {
+		var err error
+		tNode, err = m.getTreeNodeFromStream(m.currentStream)
+		if err != nil {
+			if err == io.EOF {
+				var err2 error
+				if m.currentStream, err2 = m.openNewStream(ctx); err2 != nil {
+					return nil, err2
+				}
+				continue
+			}
+			return nil, err
+		}
+		var ok bool
+		fileName, ok = tNode.FileName()
+		if !ok {
+			continue
+		}
+		if filePath, err = formFilePath(tNode, fileName, m.nodePaths); err != nil {
+			if errors.Is(err, errParentPathNotFound) {
+				filePath = fileName
+				m.nodePaths[tNode.ID[0]] = filePath
+			} else {
+				return nil, err
+			}
+		}
+		filePath = m.pathPrefix + filePath
+		if _, ok := tNode.Meta[finishedKV]; ok {
+			continue
+		}
+		if id, ok := tNode.Meta[uploadIDKV]; ok {
+			if m.keyMarker == "" || filePath > m.keyMarker || (filePath == m.keyMarker && m.uploadID != "" && id > m.uploadID) {
+				break
+			}
+		}
+	}
+
+	return newMultipartInfoFromTreeNode(m.log, filePath, tNode)
+}
+
+// openNewStream creates subtree stream from childStream`s node.
+func (m *multipartInfoStream) openNewStream(ctx context.Context) (SubTreeStream, error) {
+	node, err := m.getTreeNodeFromStream(m.childStream)
 	if err != nil {
 		return nil, err
 	}
+	if node.ID[0] == m.rootID[0] {
+		// skip root node
+		return m.openNewStream(ctx)
+	}
+	stream, err := m.treeService.GetSubTreeStream(ctx, m.bktInfo, systemTree, node.ID, maxGetSubTreeDepth)
+	if err != nil {
+		return nil, err
+	}
+	return stream, nil
+}
 
-	var parentPrefix string
+func (m *multipartInfoStream) getTreeNodeFromStream(stream SubTreeStream) (*treeNode, error) {
-	if parentFilePath != "" { // The root of subTree can also have a parent
+	node, err := stream.Next()
-		parentPrefix = strings.TrimSuffix(parentFilePath, separator) + separator // To avoid 'foo//bar'
+	if err != nil {
+		return nil, err
+	}
+	tNode, err := newTreeNode(node)
+	if err != nil {
+		return nil, err
+	}
+	return tNode, nil
+}
+
+func (c *Tree) GetMultipartUploadsByPrefix(ctx context.Context, bktInfo *data.BucketInfo, params data.MultipartStreamParams) (data.MultipartInfoStream, error) {
+	stream, rootID, err := c.getSubTreeByPrefixStream(ctx, bktInfo, systemTree, params.Prefix)
+	if err != nil {
+		if errors.Is(err, tree.ErrNodeNotFound) {
+			return nil, nil
+		}
+		return nil, err
 	}
 
-	var filepath string
+	return &multipartInfoStream{
-	namesMap := make(map[uint64]string, len(subTree))
+		log:         c.reqLogger(ctx),
-	multiparts := make(map[string][]*data.MultipartInfo, len(subTree))
+		rootID:      rootID,
-
+		childStream: stream,
-	for i, node := range subTree {
+		nodePaths:   make(map[uint64]string),
-		tNode, fileName, err := parseTreeNode(node)
+		treeService: c.service,
-		if err != nil {
+		bktInfo:     bktInfo,
-			continue
+		uploadID:    params.UploadIDMarker,
-		}
+		keyMarker:   params.KeyMarker,
-
+		pathPrefix: strings.TrimRightFunc(params.Prefix, func(r rune) bool {
-		if i != 0 {
+			return r != '/'
-			if filepath, err = formFilePath(node, fileName, namesMap); err != nil {
+		}),
-				return nil, fmt.Errorf("invalid node order: %w", err)
+	}, nil
-			}
-		} else {
-			filepath = parentPrefix + fileName
-			for _, id := range tNode.ID {
-				namesMap[id] = filepath
-			}
-		}
-
-		multipartInfo, err := newMultipartInfoFromTreeNode(c.reqLogger(ctx), filepath, tNode)
-		if err != nil || multipartInfo.Finished {
-			continue
-		}
-
-		for _, id := range node.GetParentID() {
-			key := formLatestNodeKey(id, fileName)
-			multipartInfos, ok := multiparts[key]
-			if !ok {
-				multipartInfos = []*data.MultipartInfo{multipartInfo}
-			} else {
-				multipartInfos = append(multipartInfos, multipartInfo)
-			}
-
-			multiparts[key] = multipartInfos
-		}
-	}
-
-	result := make([]*data.MultipartInfo, 0, len(multiparts))
-	for _, multipartInfo := range multiparts {
-		result = append(result, multipartInfo...)
-	}
-
-	return result, nil
 }
 
 func (c *Tree) GetMultipartUpload(ctx context.Context, bktInfo *data.BucketInfo, objectName, uploadID string) (*data.MultipartInfo, error) {