Fix list performance for large buckets: delimiter-aware shallow listing, cache TTL increase, UI delimiter streaming. header badge shows total bucket objects, fix status bar text concatenation

app/__init__.py

@@ -115,7 +115,7 @@ def create_app(
 
     storage = ObjectStorage(
         Path(app.config["STORAGE_ROOT"]),
-        cache_ttl=app.config.get("OBJECT_CACHE_TTL", 5),
+        cache_ttl=app.config.get("OBJECT_CACHE_TTL", 60),
         object_cache_max_size=app.config.get("OBJECT_CACHE_MAX_SIZE", 100),
         bucket_config_cache_ttl=app.config.get("BUCKET_CONFIG_CACHE_TTL_SECONDS", 30.0),
         object_key_max_length_bytes=app.config.get("OBJECT_KEY_MAX_LENGTH_BYTES", 1024),

app/config.py

@@ -241,7 +241,7 @@ class AppConfig:
         cors_expose_headers = _csv(str(_get("CORS_EXPOSE_HEADERS", "*")), ["*"])
         session_lifetime_days = int(_get("SESSION_LIFETIME_DAYS", 30))
         bucket_stats_cache_ttl = int(_get("BUCKET_STATS_CACHE_TTL", 60))
-        object_cache_ttl = int(_get("OBJECT_CACHE_TTL", 5))
+        object_cache_ttl = int(_get("OBJECT_CACHE_TTL", 60))
 
         encryption_enabled = str(_get("ENCRYPTION_ENABLED", "0")).lower() in {"1", "true", "yes", "on"}
         encryption_keys_dir = storage_root / ".myfsio.sys" / "keys"

app/encrypted_storage.py

@@ -189,6 +189,9 @@ class EncryptedObjectStorage:
     
     def list_objects(self, bucket_name: str, **kwargs):
         return self.storage.list_objects(bucket_name, **kwargs)
+
+    def list_objects_shallow(self, bucket_name: str, **kwargs):
+        return self.storage.list_objects_shallow(bucket_name, **kwargs)
     
     def list_objects_all(self, bucket_name: str):
         return self.storage.list_objects_all(bucket_name)

app/s3_api.py

@@ -2671,54 +2671,43 @@ def bucket_handler(bucket_name: str) -> Response:
     else:
         effective_start = marker
     
-    fetch_keys = max_keys * 10 if delimiter else max_keys
     try:
-        list_result = storage.list_objects(
-            bucket_name,
-            max_keys=fetch_keys,
-            continuation_token=effective_start or None,
-            prefix=prefix or None,
-        )
-        objects = list_result.objects
+        if delimiter:
+            shallow_result = storage.list_objects_shallow(
+                bucket_name,
+                prefix=prefix,
+                delimiter=delimiter,
+                max_keys=max_keys,
+                continuation_token=effective_start or None,
+            )
+            objects = shallow_result.objects
+            common_prefixes = shallow_result.common_prefixes
+            is_truncated = shallow_result.is_truncated
+
+            next_marker = shallow_result.next_continuation_token or ""
+            next_continuation_token = ""
+            if is_truncated and next_marker and list_type == "2":
+                next_continuation_token = base64.urlsafe_b64encode(next_marker.encode()).decode("utf-8")
+        else:
+            list_result = storage.list_objects(
+                bucket_name,
+                max_keys=max_keys,
+                continuation_token=effective_start or None,
+                prefix=prefix or None,
+            )
+            objects = list_result.objects
+            common_prefixes = []
+            is_truncated = list_result.is_truncated
+
+            next_marker = ""
+            next_continuation_token = ""
+            if is_truncated:
+                if objects:
+                    next_marker = objects[-1].key
+                if list_type == "2" and next_marker:
+                    next_continuation_token = base64.urlsafe_b64encode(next_marker.encode()).decode("utf-8")
     except StorageError as exc:
         return _error_response("NoSuchBucket", str(exc), 404)
-    
-    common_prefixes: list[str] = []
-    filtered_objects: list = []
-    if delimiter:
-        seen_prefixes: set[str] = set()
-        for obj in objects:
-            key_after_prefix = obj.key[len(prefix):] if prefix else obj.key
-            if delimiter in key_after_prefix:
-                common_prefix = prefix + key_after_prefix.split(delimiter)[0] + delimiter
-                if common_prefix not in seen_prefixes:
-                    seen_prefixes.add(common_prefix)
-                    common_prefixes.append(common_prefix)
-            else:
-                filtered_objects.append(obj)
-        objects = filtered_objects
-        common_prefixes = sorted(common_prefixes)
-    
-    total_items = len(objects) + len(common_prefixes)
-    is_truncated = total_items > max_keys or list_result.is_truncated
-    
-    if len(objects) >= max_keys:
-        objects = objects[:max_keys]
-        common_prefixes = []
-    else:
-        remaining = max_keys - len(objects)
-        common_prefixes = common_prefixes[:remaining]
-    
-    next_marker = ""
-    next_continuation_token = ""
-    if is_truncated:
-        if objects:
-            next_marker = objects[-1].key
-        elif common_prefixes:
-            next_marker = common_prefixes[-1].rstrip(delimiter) if delimiter else common_prefixes[-1]
-        
-        if list_type == "2" and next_marker:
-            next_continuation_token = base64.urlsafe_b64encode(next_marker.encode()).decode("utf-8")
 
     if list_type == "2":
         root = Element("ListBucketResult")

app/s3_client.py

@@ -245,6 +245,7 @@ def stream_objects_ndjson(
     url_templates: dict[str, str],
     display_tz: str = "UTC",
     versioning_enabled: bool = False,
+    delimiter: Optional[str] = None,
 ) -> Generator[str, None, None]:
     meta_line = json.dumps({
         "type": "meta",
@@ -258,11 +259,20 @@ def stream_objects_ndjson(
     kwargs: dict[str, Any] = {"Bucket": bucket_name, "MaxKeys": 1000}
     if prefix:
         kwargs["Prefix"] = prefix
+    if delimiter:
+        kwargs["Delimiter"] = delimiter
 
+    running_count = 0
     try:
         paginator = client.get_paginator("list_objects_v2")
         for page in paginator.paginate(**kwargs):
-            for obj in page.get("Contents", []):
+            for cp in page.get("CommonPrefixes", []):
+                yield json.dumps({
+                    "type": "folder",
+                    "prefix": cp["Prefix"],
+                }) + "\n"
+            page_contents = page.get("Contents", [])
+            for obj in page_contents:
                 last_mod = obj["LastModified"]
                 yield json.dumps({
                     "type": "object",
@@ -273,6 +283,8 @@ def stream_objects_ndjson(
                     "last_modified_iso": format_datetime_iso(last_mod, display_tz),
                     "etag": obj.get("ETag", "").strip('"'),
                 }) + "\n"
+            running_count += len(page_contents)
+            yield json.dumps({"type": "count", "total_count": running_count}) + "\n"
     except ClientError as exc:
         error_msg = exc.response.get("Error", {}).get("Message", "S3 operation failed")
         yield json.dumps({"type": "error", "error": error_msg}) + "\n"

app/storage.py

@@ -154,6 +154,15 @@ class ListObjectsResult:
     total_count: Optional[int] = None
 
 
+@dataclass
+class ShallowListResult:
+    """Result for delimiter-aware directory-level listing."""
+    objects: List[ObjectMeta]
+    common_prefixes: List[str]
+    is_truncated: bool
+    next_continuation_token: Optional[str]
+
+
 def _utcnow() -> datetime:
     return datetime.now(timezone.utc)
 
@@ -279,25 +288,41 @@ class ObjectStorage:
         version_count = 0
         version_bytes = 0
 
+        internal = self.INTERNAL_FOLDERS
+        bucket_str = str(bucket_path)
+
         try:
-            for path in bucket_path.rglob("*"):
-                if path.is_file():
-                    rel = path.relative_to(bucket_path)
-                    if not rel.parts:
-                        continue
-                    top_folder = rel.parts[0]
-                    if top_folder not in self.INTERNAL_FOLDERS:
-                        stat = path.stat()
-                        object_count += 1
-                        total_bytes += stat.st_size
+            stack = [bucket_str]
+            while stack:
+                current = stack.pop()
+                try:
+                    with os.scandir(current) as it:
+                        for entry in it:
+                            if current == bucket_str and entry.name in internal:
+                                continue
+                            if entry.is_dir(follow_symlinks=False):
+                                stack.append(entry.path)
+                            elif entry.is_file(follow_symlinks=False):
+                                object_count += 1
+                                total_bytes += entry.stat(follow_symlinks=False).st_size
+                except PermissionError:
+                    continue
 
             versions_root = self._bucket_versions_root(bucket_name)
             if versions_root.exists():
-                for path in versions_root.rglob("*.bin"):
-                    if path.is_file():
-                        stat = path.stat()
-                        version_count += 1
-                        version_bytes += stat.st_size
+                v_stack = [str(versions_root)]
+                while v_stack:
+                    v_current = v_stack.pop()
+                    try:
+                        with os.scandir(v_current) as it:
+                            for entry in it:
+                                if entry.is_dir(follow_symlinks=False):
+                                    v_stack.append(entry.path)
+                                elif entry.is_file(follow_symlinks=False) and entry.name.endswith(".bin"):
+                                    version_count += 1
+                                    version_bytes += entry.stat(follow_symlinks=False).st_size
+                    except PermissionError:
+                        continue
         except OSError:
             if cached_stats is not None:
                 return cached_stats
@@ -471,6 +496,202 @@ class ObjectStorage:
         result = self.list_objects(bucket_name, max_keys=100000)
         return result.objects
 
+    def list_objects_shallow(
+        self,
+        bucket_name: str,
+        *,
+        prefix: str = "",
+        delimiter: str = "/",
+        max_keys: int = 1000,
+        continuation_token: Optional[str] = None,
+    ) -> ShallowListResult:
+        import bisect
+
+        bucket_path = self._bucket_path(bucket_name)
+        if not bucket_path.exists():
+            raise BucketNotFoundError("Bucket does not exist")
+        bucket_id = bucket_path.name
+
+        if delimiter != "/" or (prefix and not prefix.endswith(delimiter)):
+            return self._shallow_via_full_scan(
+                bucket_name, prefix=prefix, delimiter=delimiter,
+                max_keys=max_keys, continuation_token=continuation_token,
+            )
+
+        target_dir = bucket_path
+        if prefix:
+            safe_prefix_path = Path(prefix.rstrip("/"))
+            if ".." in safe_prefix_path.parts:
+                return ShallowListResult(
+                    objects=[], common_prefixes=[],
+                    is_truncated=False, next_continuation_token=None,
+                )
+            target_dir = bucket_path / safe_prefix_path
+            try:
+                resolved = target_dir.resolve()
+                bucket_resolved = bucket_path.resolve()
+                if not str(resolved).startswith(str(bucket_resolved) + os.sep) and resolved != bucket_resolved:
+                    return ShallowListResult(
+                        objects=[], common_prefixes=[],
+                        is_truncated=False, next_continuation_token=None,
+                    )
+            except (OSError, ValueError):
+                return ShallowListResult(
+                    objects=[], common_prefixes=[],
+                    is_truncated=False, next_continuation_token=None,
+                )
+
+        if not target_dir.exists() or not target_dir.is_dir():
+            return ShallowListResult(
+                objects=[], common_prefixes=[],
+                is_truncated=False, next_continuation_token=None,
+            )
+
+        etag_index_path = self._system_bucket_root(bucket_id) / "etag_index.json"
+        meta_cache: Dict[str, str] = {}
+        if etag_index_path.exists():
+            try:
+                with open(etag_index_path, 'r', encoding='utf-8') as f:
+                    meta_cache = json.load(f)
+            except (OSError, json.JSONDecodeError):
+                pass
+
+        entries_files: list[tuple[str, int, float, Optional[str]]] = []
+        entries_dirs: list[str] = []
+
+        try:
+            with os.scandir(str(target_dir)) as it:
+                for entry in it:
+                    name = entry.name
+                    if name in self.INTERNAL_FOLDERS:
+                        continue
+                    if entry.is_dir(follow_symlinks=False):
+                        cp = prefix + name + delimiter
+                        entries_dirs.append(cp)
+                    elif entry.is_file(follow_symlinks=False):
+                        key = prefix + name
+                        try:
+                            st = entry.stat()
+                            etag = meta_cache.get(key)
+                            entries_files.append((key, st.st_size, st.st_mtime, etag))
+                        except OSError:
+                            pass
+        except OSError:
+            return ShallowListResult(
+                objects=[], common_prefixes=[],
+                is_truncated=False, next_continuation_token=None,
+            )
+
+        entries_dirs.sort()
+        entries_files.sort(key=lambda x: x[0])
+
+        all_items: list[tuple[str, bool]] = []
+        fi, di = 0, 0
+        while fi < len(entries_files) and di < len(entries_dirs):
+            if entries_files[fi][0] <= entries_dirs[di]:
+                all_items.append((entries_files[fi][0], False))
+                fi += 1
+            else:
+                all_items.append((entries_dirs[di], True))
+                di += 1
+        while fi < len(entries_files):
+            all_items.append((entries_files[fi][0], False))
+            fi += 1
+        while di < len(entries_dirs):
+            all_items.append((entries_dirs[di], True))
+            di += 1
+
+        files_map = {e[0]: e for e in entries_files}
+
+        start_index = 0
+        if continuation_token:
+            all_keys = [item[0] for item in all_items]
+            start_index = bisect.bisect_right(all_keys, continuation_token)
+
+        selected = all_items[start_index:start_index + max_keys]
+        is_truncated = (start_index + max_keys) < len(all_items)
+
+        result_objects: list[ObjectMeta] = []
+        result_prefixes: list[str] = []
+        for item_key, is_dir in selected:
+            if is_dir:
+                result_prefixes.append(item_key)
+            else:
+                fdata = files_map[item_key]
+                result_objects.append(ObjectMeta(
+                    key=fdata[0],
+                    size=fdata[1],
+                    last_modified=datetime.fromtimestamp(fdata[2], timezone.utc),
+                    etag=fdata[3],
+                    metadata=None,
+                ))
+
+        next_token = None
+        if is_truncated and selected:
+            next_token = selected[-1][0]
+
+        return ShallowListResult(
+            objects=result_objects,
+            common_prefixes=result_prefixes,
+            is_truncated=is_truncated,
+            next_continuation_token=next_token,
+        )
+
+    def _shallow_via_full_scan(
+        self,
+        bucket_name: str,
+        *,
+        prefix: str = "",
+        delimiter: str = "/",
+        max_keys: int = 1000,
+        continuation_token: Optional[str] = None,
+    ) -> ShallowListResult:
+        list_result = self.list_objects(
+            bucket_name,
+            max_keys=max_keys * 10,
+            continuation_token=continuation_token,
+            prefix=prefix or None,
+        )
+
+        common_prefixes: list[str] = []
+        filtered_objects: list[ObjectMeta] = []
+        seen_prefixes: set[str] = set()
+
+        for obj in list_result.objects:
+            key_after_prefix = obj.key[len(prefix):] if prefix else obj.key
+            if delimiter in key_after_prefix:
+                cp = prefix + key_after_prefix.split(delimiter)[0] + delimiter
+                if cp not in seen_prefixes:
+                    seen_prefixes.add(cp)
+                    common_prefixes.append(cp)
+            else:
+                filtered_objects.append(obj)
+
+        common_prefixes.sort()
+        total_items = len(filtered_objects) + len(common_prefixes)
+        is_truncated = total_items > max_keys or list_result.is_truncated
+
+        if len(filtered_objects) >= max_keys:
+            filtered_objects = filtered_objects[:max_keys]
+            common_prefixes = []
+        else:
+            remaining = max_keys - len(filtered_objects)
+            common_prefixes = common_prefixes[:remaining]
+
+        next_token = None
+        if is_truncated:
+            if filtered_objects:
+                next_token = filtered_objects[-1].key
+            elif common_prefixes:
+                next_token = common_prefixes[-1].rstrip(delimiter) if delimiter else common_prefixes[-1]
+
+        return ShallowListResult(
+            objects=filtered_objects,
+            common_prefixes=common_prefixes,
+            is_truncated=is_truncated,
+            next_continuation_token=next_token,
+        )
+
     def put_object(
         self,
         bucket_name: str,

app/ui.py

@@ -616,6 +616,7 @@ def stream_bucket_objects(bucket_name: str):
         return jsonify({"error": str(exc)}), 403
 
     prefix = request.args.get("prefix") or None
+    delimiter = request.args.get("delimiter") or None
 
     try:
         client = get_session_s3_client()
@@ -629,6 +630,7 @@ def stream_bucket_objects(bucket_name: str):
     return Response(
         stream_objects_ndjson(
             client, bucket_name, prefix, url_templates, display_tz, versioning_enabled,
+            delimiter=delimiter,
         ),
         mimetype='application/x-ndjson',
         headers={

static/js/bucket-detail-main.js

@@ -167,6 +167,8 @@
   let pageSize = 5000;
   let currentPrefix = '';
   let allObjects = [];
+  let streamFolders = [];
+  let useDelimiterMode = true;
   let urlTemplates = null;
   let streamAbortController = null;
   let useStreaming = !!objectsStreamUrl;
@@ -186,7 +188,7 @@
   let renderedRange = { start: 0, end: 0 };
 
   let memoizedVisibleItems = null;
-  let memoizedInputs = { objectCount: -1, prefix: null, filterTerm: null };
+  let memoizedInputs = { objectCount: -1, folderCount: -1, prefix: null, filterTerm: null };
 
   const createObjectRow = (obj, displayKey = null) => {
     const tr = document.createElement('tr');
@@ -319,10 +321,13 @@
     `;
   };
 
+  const bucketTotalObjects = objectsContainer ? parseInt(objectsContainer.dataset.bucketTotalObjects || '0', 10) : 0;
+
   const updateObjectCountBadge = () => {
     if (!objectCountBadge) return;
-    if (totalObjectCount === 0) {
-      objectCountBadge.textContent = '0 objects';
+    if (useDelimiterMode) {
+      const total = bucketTotalObjects || totalObjectCount;
+      objectCountBadge.textContent = `${total.toLocaleString()} object${total !== 1 ? 's' : ''}`;
     } else {
       objectCountBadge.textContent = `${totalObjectCount.toLocaleString()} object${totalObjectCount !== 1 ? 's' : ''}`;
     }
@@ -349,6 +354,7 @@
   const computeVisibleItems = (forceRecompute = false) => {
     const currentInputs = {
       objectCount: allObjects.length,
+      folderCount: streamFolders.length,
       prefix: currentPrefix,
       filterTerm: currentFilterTerm,
       sortField: currentSortField,
@@ -358,6 +364,7 @@
     if (!forceRecompute &&
         memoizedVisibleItems !== null &&
         memoizedInputs.objectCount === currentInputs.objectCount &&
+        memoizedInputs.folderCount === currentInputs.folderCount &&
         memoizedInputs.prefix === currentInputs.prefix &&
         memoizedInputs.filterTerm === currentInputs.filterTerm &&
         memoizedInputs.sortField === currentInputs.sortField &&
@@ -366,36 +373,53 @@
     }
 
     const items = [];
-    const folders = new Set();
 
-    allObjects.forEach(obj => {
-      if (!obj.key.startsWith(currentPrefix)) return;
-
-      const remainder = obj.key.slice(currentPrefix.length);
-
-      if (!remainder) return;
-
-      const isFolderMarker = obj.key.endsWith('/') && obj.size === 0;
-      const slashIndex = remainder.indexOf('/');
-
-      if (slashIndex === -1 && !isFolderMarker) {
+    if (useDelimiterMode && streamFolders.length > 0) {
+      streamFolders.forEach(folderPath => {
+        const folderName = folderPath.slice(currentPrefix.length).replace(/\/$/, '');
+        if (!currentFilterTerm || folderName.toLowerCase().includes(currentFilterTerm)) {
+          items.push({ type: 'folder', path: folderPath, displayKey: folderName });
+        }
+      });
+      allObjects.forEach(obj => {
+        const remainder = obj.key.slice(currentPrefix.length);
+        if (!remainder) return;
         if (!currentFilterTerm || remainder.toLowerCase().includes(currentFilterTerm)) {
           items.push({ type: 'file', data: obj, displayKey: remainder });
         }
-      } else {
-        const effectiveSlashIndex = isFolderMarker && slashIndex === remainder.length - 1
-          ? slashIndex
-          : (slashIndex === -1 ? remainder.length - 1 : slashIndex);
-        const folderName = remainder.slice(0, effectiveSlashIndex);
-        const folderPath = currentPrefix + folderName + '/';
-        if (!folders.has(folderPath)) {
-          folders.add(folderPath);
-          if (!currentFilterTerm || folderName.toLowerCase().includes(currentFilterTerm)) {
-            items.push({ type: 'folder', path: folderPath, displayKey: folderName });
+      });
+    } else {
+      const folders = new Set();
+
+      allObjects.forEach(obj => {
+        if (!obj.key.startsWith(currentPrefix)) return;
+
+        const remainder = obj.key.slice(currentPrefix.length);
+
+        if (!remainder) return;
+
+        const isFolderMarker = obj.key.endsWith('/') && obj.size === 0;
+        const slashIndex = remainder.indexOf('/');
+
+        if (slashIndex === -1 && !isFolderMarker) {
+          if (!currentFilterTerm || remainder.toLowerCase().includes(currentFilterTerm)) {
+            items.push({ type: 'file', data: obj, displayKey: remainder });
+          }
+        } else {
+          const effectiveSlashIndex = isFolderMarker && slashIndex === remainder.length - 1
+            ? slashIndex
+            : (slashIndex === -1 ? remainder.length - 1 : slashIndex);
+          const folderName = remainder.slice(0, effectiveSlashIndex);
+          const folderPath = currentPrefix + folderName + '/';
+          if (!folders.has(folderPath)) {
+            folders.add(folderPath);
+            if (!currentFilterTerm || folderName.toLowerCase().includes(currentFilterTerm)) {
+              items.push({ type: 'folder', path: folderPath, displayKey: folderName });
+            }
           }
         }
-      }
-    });
+      });
+    }
 
     items.sort((a, b) => {
       if (a.type === 'folder' && b.type === 'file') return -1;
@@ -471,7 +495,7 @@
     renderedRange = { start: -1, end: -1 };
 
     if (visibleItems.length === 0) {
-      if (allObjects.length === 0 && !hasMoreObjects) {
+      if (allObjects.length === 0 && streamFolders.length === 0 && !hasMoreObjects) {
         showEmptyState();
       } else {
         objectsTableBody.innerHTML = `
@@ -500,15 +524,7 @@
   const updateFolderViewStatus = () => {
     const folderViewStatusEl = document.getElementById('folder-view-status');
     if (!folderViewStatusEl) return;
-
-    if (currentPrefix) {
-      const folderCount = visibleItems.filter(i => i.type === 'folder').length;
-      const fileCount = visibleItems.filter(i => i.type === 'file').length;
-      folderViewStatusEl.innerHTML = `<span class="text-muted">${folderCount} folder${folderCount !== 1 ? 's' : ''}, ${fileCount} file${fileCount !== 1 ? 's' : ''} in this view</span>`;
-      folderViewStatusEl.classList.remove('d-none');
-    } else {
-      folderViewStatusEl.classList.add('d-none');
-    }
+    folderViewStatusEl.classList.add('d-none');
   };
 
   const processStreamObject = (obj) => {
@@ -536,21 +552,30 @@
   let lastStreamRenderTime = 0;
   const STREAM_RENDER_THROTTLE_MS = 500;
 
+  const buildBottomStatusText = (complete) => {
+    if (!complete) {
+      const countText = totalObjectCount > 0 ? ` of ${totalObjectCount.toLocaleString()}` : '';
+      return `${loadedObjectCount.toLocaleString()}${countText} loading...`;
+    }
+    const parts = [];
+    if (useDelimiterMode && streamFolders.length > 0) {
+      parts.push(`${streamFolders.length.toLocaleString()} folder${streamFolders.length !== 1 ? 's' : ''}`);
+    }
+    parts.push(`${loadedObjectCount.toLocaleString()} object${loadedObjectCount !== 1 ? 's' : ''}`);
+    return parts.join(', ');
+  };
+
   const flushPendingStreamObjects = () => {
-    if (pendingStreamObjects.length === 0) return;
-    const batch = pendingStreamObjects.splice(0, pendingStreamObjects.length);
-    batch.forEach(obj => {
-      loadedObjectCount++;
-      allObjects.push(obj);
-    });
+    if (pendingStreamObjects.length > 0) {
+      const batch = pendingStreamObjects.splice(0, pendingStreamObjects.length);
+      batch.forEach(obj => {
+        loadedObjectCount++;
+        allObjects.push(obj);
+      });
+    }
     updateObjectCountBadge();
     if (loadMoreStatus) {
-      if (streamingComplete) {
-        loadMoreStatus.textContent = `${loadedObjectCount.toLocaleString()} objects`;
-      } else {
-        const countText = totalObjectCount > 0 ? ` of ${totalObjectCount.toLocaleString()}` : '';
-        loadMoreStatus.textContent = `${loadedObjectCount.toLocaleString()}${countText} loading...`;
-      }
+      loadMoreStatus.textContent = buildBottomStatusText(streamingComplete);
     }
     if (objectsLoadingRow && objectsLoadingRow.parentNode) {
       const loadingText = objectsLoadingRow.querySelector('p');
@@ -585,8 +610,9 @@
     loadedObjectCount = 0;
     totalObjectCount = 0;
     allObjects = [];
+    streamFolders = [];
     memoizedVisibleItems = null;
-    memoizedInputs = { objectCount: -1, prefix: null, filterTerm: null };
+    memoizedInputs = { objectCount: -1, folderCount: -1, prefix: null, filterTerm: null };
     pendingStreamObjects = [];
     lastStreamRenderTime = 0;
 
@@ -595,6 +621,7 @@
     try {
       const params = new URLSearchParams();
       if (currentPrefix) params.set('prefix', currentPrefix);
+      if (useDelimiterMode) params.set('delimiter', '/');
 
       const response = await fetch(`${objectsStreamUrl}?${params}`, {
         signal: streamAbortController.signal
@@ -639,6 +666,10 @@
                   if (loadingText) loadingText.textContent = `Loading 0 of ${totalObjectCount.toLocaleString()} objects...`;
                 }
                 break;
+              case 'folder':
+                streamFolders.push(msg.prefix);
+                scheduleStreamRender();
+                break;
               case 'object':
                 pendingStreamObjects.push(processStreamObject(msg));
                 if (pendingStreamObjects.length >= STREAM_RENDER_BATCH) {
@@ -682,7 +713,7 @@
       }
 
       if (loadMoreStatus) {
-        loadMoreStatus.textContent = `${loadedObjectCount.toLocaleString()} objects`;
+        loadMoreStatus.textContent = buildBottomStatusText(true);
       }
       refreshVirtualList();
       renderBreadcrumb(currentPrefix);
@@ -710,8 +741,9 @@
       loadedObjectCount = 0;
       totalObjectCount = 0;
       allObjects = [];
+      streamFolders = [];
       memoizedVisibleItems = null;
-      memoizedInputs = { objectCount: -1, prefix: null, filterTerm: null };
+      memoizedInputs = { objectCount: -1, folderCount: -1, prefix: null, filterTerm: null };
     }
 
     if (append && loadMoreSpinner) {
@@ -913,7 +945,7 @@
     });
   }
 
-  const hasFolders = () => allObjects.some(obj => obj.key.includes('/'));
+  const hasFolders = () => streamFolders.length > 0 || allObjects.some(obj => obj.key.includes('/'));
 
   const getFoldersAtPrefix = (prefix) => {
     const folders = new Set();
@@ -940,6 +972,9 @@
   };
 
   const countObjectsInFolder = (folderPrefix) => {
+    if (useDelimiterMode) {
+      return { count: 0, mayHaveMore: true };
+    }
     const count = allObjects.filter(obj => obj.key.startsWith(folderPrefix)).length;
     return { count, mayHaveMore: hasMoreObjects };
   };
@@ -1018,7 +1053,13 @@
   const createFolderRow = (folderPath, displayName = null) => {
     const folderName = displayName || folderPath.slice(currentPrefix.length).replace(/\/$/, '');
     const { count: objectCount, mayHaveMore } = countObjectsInFolder(folderPath);
-    const countDisplay = mayHaveMore ? `${objectCount}+` : objectCount;
+    let countLine = '';
+    if (useDelimiterMode) {
+      countLine = '';
+    } else {
+      const countDisplay = mayHaveMore ? `${objectCount}+` : objectCount;
+      countLine = `<div class="text-muted small ms-4 ps-2">${countDisplay} object${objectCount !== 1 ? 's' : ''}</div>`;
+    }
 
     const tr = document.createElement('tr');
     tr.className = 'folder-row';
@@ -1036,7 +1077,7 @@
           </svg>
           <span>${escapeHtml(folderName)}/</span>
         </div>
-        <div class="text-muted small ms-4 ps-2">${countDisplay} object${objectCount !== 1 ? 's' : ''}</div>
+        ${countLine}
       </td>
       <td class="text-end text-nowrap">
         <span class="text-muted small">—</span>

templates/bucket_detail.html

@@ -171,6 +171,7 @@
         data-bulk-download-endpoint="{{ url_for('ui.bulk_download_objects', bucket_name=bucket_name) }}"
         data-folders-url="{{ folders_url }}"
         data-buckets-for-copy-url="{{ buckets_for_copy_url }}"
+        data-bucket-total-objects="{{ bucket_stats.get('objects', 0) }}"
       >
         <table class="table table-hover align-middle mb-0" id="objects-table" style="table-layout: fixed;">
           <thead class="table-light">