Fix: google storage init with sa and download (langgenius#5054)

api/extensions/storage/google_storage.py

@@ -1,5 +1,6 @@
 import base64
 import io
+import json
 from collections.abc import Generator
 from contextlib import closing
 
@@ -20,7 +21,9 @@ def __init__(self, app: Flask):
         # if service_account_json_str is empty, use Application Default Credentials
         if service_account_json_str:
             service_account_json = base64.b64decode(service_account_json_str).decode('utf-8')
-            self.client = GoogleCloudStorage.Client.from_service_account_info(service_account_json)
+            # convert str to object
+            service_account_obj = json.loads(service_account_json)
+            self.client = GoogleCloudStorage.Client.from_service_account_info(service_account_obj)
         else:
             self.client = GoogleCloudStorage.Client()
 
@@ -48,9 +51,7 @@ def generate(filename: str = filename) -> Generator:
     def download(self, filename, target_filepath):
         bucket = self.client.get_bucket(self.bucket_name)
         blob = bucket.get_blob(filename)
-        with open(target_filepath, "wb") as my_blob:
-            blob_data = blob.download_blob()
-            blob_data.readinto(my_blob)
+        blob.download_to_filename(target_filepath)
 
     def exists(self, filename):
         bucket = self.client.get_bucket(self.bucket_name)