From 66c4d85f51a9fb5ca0afc23cec9b20850e7f6f3e Mon Sep 17 00:00:00 2001
From: Amy Wu <wuamy@google.com>
Date: Thu, 29 Jan 2026 13:41:38 -0800
Subject: [PATCH] fix: support custom credentials in RAG.upload_file

fixes #4986

PiperOrigin-RevId: 862881532
---
 vertexai/rag/rag_data.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/vertexai/rag/rag_data.py b/vertexai/rag/rag_data.py
index a1eaa98120..fd4ca0d7e6 100644
--- a/vertexai/rag/rag_data.py
+++ b/vertexai/rag/rag_data.py
@@ -428,7 +428,9 @@ def upload_file(
         "metadata": (None, str(js_rag_file)),
         "file": open(path, "rb"),
     }
-    credentials, _ = auth.default()
+    credentials = initializer.global_config.credentials
+    if not credentials:
+        credentials, _ = auth.default()
     authorized_session = google_auth_requests.AuthorizedSession(credentials=credentials)
     try:
         response = authorized_session.post(