fix: introduce timeout for outgoing A2A requests from AgentEngine

PiperOrigin-RevId: 891315397

Author: vertex-sdk-bot

tests/unit/vertexai/genai/replays/test_agent_engine_a2a_methods.py

@@ -0,0 +1,92 @@
+# Copyright 2026 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# pylint: disable=protected-access,bad-continuation,missing-function-docstring
+
+from unittest import mock
+
+from tests.unit.vertexai.genai.replays import pytest_helper
+from vertexai._genai import types
+from google.genai import _api_client
+import httpx
+import pytest
+
+
+pytest.importorskip(
+    "a2a.client.errors", reason="a2a-sdk not installed, skipping Agent Engine A2A tests"
+)
+from a2a.client import (  # noqa: E402  # pylint: disable=g-import-not-at-top,g-bad-import-order
+    errors as a2a_errors,
+)
+
+pytest_plugins = ("pytest_asyncio",)
+
+
+@pytest.mark.asyncio
+async def test_timeout_is_set(client):
+    agent_engine = client.agent_engines.get(
+        name="projects/932854658080/locations/us-central1/reasoningEngines/857830725653626880",
+    )
+    assert isinstance(agent_engine, types.AgentEngine)
+
+    message_data = {
+        "messageId": "msg-123",
+        "role": "user",
+        "parts": [
+            {"kind": "text", "text": "Where will be the Super Bowl held in 2026?"}
+        ],
+    }
+    with mock.patch(
+        "httpx.AsyncClient", spec=httpx.AsyncClient
+    ) as mock_async_client_factory:
+        # Replay mode does not capture A2A calls so instead of relying on the
+        # real service, we simulate a failed call.
+        mock_response = httpx.Response(
+            401,
+            request=httpx.Request("POST", "url"),
+            json={
+                "error": {
+                    "code": "UNAUTHENTICATED",
+                    "message": "Authentication failed: Missing or invalid API key.",
+                }
+            },
+        )
+        mock_async_client_instance = mock_async_client_factory.return_value
+        mock_async_client_instance.post.return_value = mock_response
+        mock_async_client_instance.send.return_value = mock_response
+
+        # These credentials are missing in replay mode, so we need to set a fake
+        # value. (This is not necessary in record mode.)
+        class FakeCredentials:
+            token = "fake-token"
+
+        agent_engine.api_client._api_client._credentials = FakeCredentials()
+
+        try:
+            await agent_engine.on_message_send(**message_data)
+        except a2a_errors.A2AClientHTTPError as e:
+            # Make sure that the authentication error was successfully
+            # propagated, otherwise the test is not valid.
+            assert e.status_code == 401
+
+    mock_async_client_factory.assert_called_once()
+    assert mock_async_client_factory.call_args.kwargs["timeout"] == 99.0
+
+
+pytestmark = pytest_helper.setup(
+    file=__file__,
+    globals_for_file=globals(),
+    test_method="agent_engines.get",
+    http_options=_api_client.HttpOptions(timeout=99000),
+)

vertexai/_genai/_agent_engines_utils.py

@@ -1822,7 +1822,12 @@ async def _method(self, **kwargs) -> Any:  # type: ignore[no-untyped-def]
                     "Authorization": (
                         f"Bearer {self.api_client._api_client._credentials.token}"
                     )
-                }
+                },
+                timeout=(
+                    self.api_client._api_client._http_options.timeout / 1000.0
+                    if self.api_client._api_client._http_options.timeout
+                    else None
+                ),
             ),
         )
         factory = ClientFactory(config)