chore: import upstream snapshot with attribution

tests/unittests/a2a/integration/client.py

@@ -0,0 +1,85 @@
+# 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.
+
+"""A2A Client for integration tests."""
+
+from a2a.client.client_factory import ClientFactory as A2AClientFactory
+from a2a.extensions.common import HTTP_EXTENSION_HEADER
+from google.adk.a2a import _compat
+from google.adk.a2a.agent.interceptors.new_integration_extension import _NEW_A2A_ADK_INTEGRATION_EXTENSION
+from google.adk.agents.remote_a2a_agent import RemoteA2aAgent
+import httpx
+
+from .server import agent_card
+
+
+def create_client(app, streaming: bool = False) -> RemoteA2aAgent:
+  """Creates a RemoteA2aAgent connected to the provided FastAPI app.
+
+  Args:
+    app: The FastAPI application (server) to connect to.
+    streaming: Whether to enable streaming mode in the client.
+
+  Returns:
+    A RemoteA2aAgent instance.
+  """
+
+  client = httpx.AsyncClient(
+      transport=httpx.ASGITransport(app=app), base_url="http://test"
+  )
+
+  client_config = _compat.make_client_config(
+      httpx_client=client,
+      streaming=streaming,
+      polling=False,
+  )
+  factory = A2AClientFactory(config=client_config)
+
+  # use_legacy=False forces the new implementation
+  agent = RemoteA2aAgent(
+      name="remote_agent",
+      agent_card=agent_card,
+      a2a_client_factory=factory,
+      use_legacy=False,
+  )
+
+  return agent
+
+
+def create_a2a_client(app, streaming: bool = False):
+  """Creates a bare A2A Client connected to the provided FastAPI app.
+
+  This is in contrast to create_client, which wraps the a2a_client into a
+  RemoteA2aAgent for the standard runner framework ecosystem execution.
+
+  Args:
+    app: The FastAPI application (server) to connect to.
+    streaming: Whether to enable streaming mode in the client.
+
+  Returns:
+    An A2A Client instance.
+  """
+  client = httpx.AsyncClient(
+      transport=httpx.ASGITransport(app=app),
+      base_url="http://test",
+      headers={HTTP_EXTENSION_HEADER: _NEW_A2A_ADK_INTEGRATION_EXTENSION},
+  )
+
+  client_config = _compat.make_client_config(
+      httpx_client=client,
+      streaming=streaming,
+      polling=False,
+  )
+  factory = A2AClientFactory(config=client_config)
+  return factory.create(agent_card)