chore: use botocore.UNSIGNED to prevent IMDS timeout in bedrock (#692)

Author: cosmin-staicu

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "uipath-langchain"
-version = "0.8.22"
+version = "0.8.23"
 description = "Python SDK that enables developers to build and deploy LangGraph agents to the UiPath Cloud Platform"
 readme = { file = "README.md", content-type = "text/markdown" }
 requires-python = ">=3.11"

src/uipath_langchain/chat/bedrock.py

@@ -108,6 +108,7 @@ def get_client(self):
                     "total_max_attempts": 1,
                 },
                 read_timeout=300,
+                signature_version=botocore.UNSIGNED,
             ),
         )
         client.meta.events.register(

tests/chat/test_bedrock.py

@@ -1,12 +1,38 @@
+import logging
 import os
 from unittest.mock import patch
 
+import botocore
 from langchain_aws import ChatBedrock
 from langchain_core.messages import AIMessage, BaseMessage, HumanMessage
 from langchain_core.messages.content import create_file_block
 from langchain_core.outputs import ChatGeneration, ChatResult
 
-from uipath_langchain.chat.bedrock import UiPathChatBedrock
+from uipath_langchain.chat.bedrock import (
+    AwsBedrockCompletionsPassthroughClient,
+    UiPathChatBedrock,
+)
+
+
+class TestGetClientSkipsImds:
+    def test_client_creation_does_not_trigger_credential_resolution(self, caplog):
+        passthrough = AwsBedrockCompletionsPassthroughClient(
+            model="anthropic.claude-haiku-4-5-20251001",
+            token="test-token",
+            api_flavor="converse",
+        )
+
+        with caplog.at_level(logging.DEBUG, logger="botocore"):
+            client = passthrough.get_client()
+
+        assert caplog.records
+        credential_log_records = [
+            r for r in caplog.records if r.name.startswith("botocore.credentials")
+        ]
+        assert not credential_log_records, (
+            f"Unexpected credential resolution: {[r.getMessage() for r in credential_log_records]}"
+        )
+        assert client._request_signer._signature_version == botocore.UNSIGNED
 
 
 class TestConvertFileBlocksToAnthropicDocuments: