fix: Neptune bulk load bad request (#2305)

Author: LeonLuttenberger

awswrangler/neptune/_client.py

@@ -1,6 +1,7 @@
 # mypy: disable-error-code=name-defined
 """Amazon NeptuneClient Module."""
 
+import json
 import logging
 from typing import Any, Dict, List, Optional, TypedDict, Union, cast
 
@@ -378,7 +379,12 @@ def load(
 
         url = f"https://{self.host}:{self.port}/loader"
 
-        req = self._prepare_request("POST", url, data=data)
+        req = self._prepare_request(
+            method="POST",
+            url=url,
+            data=json.dumps(data),
+            headers={"Content-Type": "application/json; charset=utf-8"},
+        )
         res = self._http_session.send(req)
 
         _logger.debug(res)

tests/unit/test_neptune.py

@@ -2,14 +2,15 @@
 import random
 import string
 import uuid
-from typing import Any, Dict
+from typing import Any, Dict, Optional
 
 import numpy as np
 import pytest  # type: ignore
 from gremlin_python.process.traversal import Direction, T
 
 import awswrangler as wr
 import awswrangler.pandas as pd
+from awswrangler.neptune._client import BulkLoadParserConfiguration
 
 from .._utils import extract_cloudformation_outputs
 
@@ -259,8 +260,20 @@ def test_gremlin_bulk_load_error_when_files_present(
         )
 
 
+DEFAULT_PARSER_CONFIGURATION = BulkLoadParserConfiguration(
+    namedGraphUri="http://aws.amazon.com/neptune/vocab/v01/DefaultNamedGraph",
+    baseUri="http://aws.amazon.com/neptune/default",
+    allowEmptyStrings=False,
+)
+
+
+@pytest.mark.parametrize("parser_config", [None, DEFAULT_PARSER_CONFIGURATION])
 def test_gremlin_bulk_load_from_files(
-    neptune_endpoint: str, neptune_port: int, neptune_load_iam_role_arn: str, path: str
+    neptune_endpoint: str,
+    neptune_port: int,
+    neptune_load_iam_role_arn: str,
+    path: str,
+    parser_config: Optional[BulkLoadParserConfiguration],
 ) -> None:
     client = wr.neptune.connect(neptune_endpoint, neptune_port, iam_enabled=False)
 
@@ -274,6 +287,7 @@ def test_gremlin_bulk_load_from_files(
         client=client,
         path=path,
         iam_role=neptune_load_iam_role_arn,
+        parser_configuration=parser_config,
     )
     res_df = wr.neptune.execute_gremlin(client, f"g.V().hasLabel('{label}').valueMap().with(WithOptions.tokens)")