UBERF-8578: Fix extra stat call for storage adapter (#7132)

Signed-off-by: Andrey Sobolev <haiodo@gmail.com>

server/collaboration/src/utils/storage.ts

@@ -28,17 +28,20 @@ export async function yDocFromStorage (
   ydoc?: YDoc
 ): Promise<YDoc | undefined> {
   // stat the object to ensure it exists, because read will throw an error in this case
-  const blob = await storageAdapter.stat(ctx, workspace, documentId)
-  if (blob === undefined) {
-    return undefined
+  try {
+    const buffer = await storageAdapter.read(ctx, workspace, documentId)
+
+    // no need to apply gc because we load existing document
+    // it is either already gc-ed, or gc not needed and it is disabled
+    ydoc ??= new YDoc({ guid: generateId(), gc: false })
+
+    return yDocFromBuffer(Buffer.concat(buffer as any), ydoc)
+  } catch (err: any) {
+    if (err.code === 'NoSuchKey') {
+      return undefined
+    }
+    throw err
   }
-
-  // no need to apply gc because we load existing document
-  // it is either already gc-ed, or gc not needed and it is disabled
-  ydoc ??= new YDoc({ guid: generateId(), gc: false })
-
-  const buffer = await storageAdapter.read(ctx, workspace, documentId)
-  return yDocFromBuffer(Buffer.concat(buffer as any), ydoc)
 }
 
 /** @public */