chore: import upstream snapshot with attribution

tests/unittests/a2a/integration/server.py

@@ -0,0 +1,164 @@
+# 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 Server for integration tests."""
+
+from unittest.mock import AsyncMock
+from unittest.mock import Mock
+
+try:
+  from a2a.server.apps.jsonrpc.fastapi_app import A2AFastAPIApplication
+  from a2a.server.request_handlers.default_request_handler import DefaultRequestHandler
+  from a2a.server.tasks.inmemory_task_store import InMemoryTaskStore
+except ImportError:
+  A2AFastAPIApplication = None
+  DefaultRequestHandler = None
+  InMemoryTaskStore = None
+from google.adk.a2a import _compat
+from google.adk.a2a.executor.a2a_agent_executor import A2aAgentExecutor
+from google.adk.a2a.executor.config import A2aAgentExecutorConfig
+from google.adk.agents.base_agent import BaseAgent
+from google.adk.artifacts.in_memory_artifact_service import InMemoryArtifactService
+from google.adk.runners import Runner
+from google.adk.sessions.in_memory_session_service import InMemorySessionService
+from google.genai import types
+
+
+class FakeRunner(Runner):
+  """A Fake Runner that delegates run_async to a provided function."""
+
+  def __init__(self, run_async_fn):
+    agent = Mock(spec=BaseAgent)
+    agent.name = "FakeAgent"
+
+    session_service = InMemorySessionService()
+    super().__init__(
+        app_name="FakeApp",
+        agent=agent,
+        session_service=session_service,
+    )
+    self.run_async_fn = run_async_fn
+
+    mock_artifact_service = Mock()
+    mock_artifact_service.load_artifact = AsyncMock(
+        return_value=types.Part(text="artifact content")
+    )
+    self.artifact_service = mock_artifact_service
+
+  async def run_async(self, **kwargs):
+    async for event in self.run_async_fn(**kwargs):
+      yield event
+
+
+if _compat.IS_A2A_V1:
+  agent_card = _compat.parse_agent_card({
+      "name": "remote_agent",
+      "description": "A fun fact generator agent",
+      "version": "0.0.1",
+      "supported_interfaces": [
+          {"url": "http://test", "protocol_binding": "JSONRPC"}
+      ],
+      "default_input_modes": ["text/plain"],
+      "default_output_modes": ["text/plain"],
+  })
+else:
+  agent_card = _compat.parse_agent_card({
+      "name": "remote_agent",
+      "url": "http://test",
+      "description": "A fun fact generator agent",
+      "capabilities": {"streaming": True},
+      "version": "0.0.1",
+      "defaultInputModes": ["text/plain"],
+      "defaultOutputModes": ["text/plain"],
+      "skills": [],
+  })
+
+
+def create_server_app(
+    run_async_fn=None,
+    config: A2aAgentExecutorConfig | None = None,
+    task_store=None,
+):
+  """Creates an A2A FastAPI application with a mocked runner.
+
+  Args:
+    run_async_fn: A generator function that takes **kwargs and yields Event
+      objects.
+    config: Optional executor configuration.
+    task_store: Optional task store instance. Defaults to InMemoryTaskStore.
+
+  Returns:
+    A FastAPI application instance.
+  """
+  runner = FakeRunner(run_async_fn)
+  executor = A2aAgentExecutor(runner=runner, config=config)
+  if task_store is None:
+    task_store = InMemoryTaskStore()
+  handler = DefaultRequestHandler(
+      agent_executor=executor, task_store=task_store
+  )
+
+  app = A2AFastAPIApplication(agent_card=agent_card, http_handler=handler)
+  return app.build()
+
+
+class _FixedContentArtifactService(InMemoryArtifactService):
+  """``InMemoryArtifactService`` whose ``load_artifact`` always returns content."""
+
+  async def load_artifact(self, **kwargs):
+    return types.Part(text="artifact content")
+
+
+class FakeRunnerV1(Runner):
+  """A Fake Runner for 1.x with a real in-memory artifact service."""
+
+  def __init__(self, run_async_fn):
+    agent = Mock(spec=BaseAgent)
+    agent.name = "FakeAgent"
+    super().__init__(
+        app_name="FakeApp",
+        agent=agent,
+        session_service=InMemorySessionService(),
+        artifact_service=_FixedContentArtifactService(),
+    )
+    self.run_async_fn = run_async_fn
+
+  async def run_async(self, **kwargs):
+    async for event in self.run_async_fn(**kwargs):
+      yield event
+
+
+def create_server_app_v1(
+    run_async_fn=None, config: A2aAgentExecutorConfig | None = None
+):
+  """Creates a 1.x Starlette app hosting an A2A executor (JSON-RPC routes).
+
+  Mirrors ``create_server_app`` but uses the 1.x route-factory path via
+  ``_compat.attach_a2a_routes_to_app`` instead of the 0.3-only
+  ``A2AFastAPIApplication``. Returns the Starlette app; callers must drive the
+  app's lifespan so the routes are attached before sending requests.
+  """
+  from a2a.server.tasks import InMemoryTaskStore as TaskStore
+  from starlette.applications import Starlette
+
+  runner = FakeRunnerV1(run_async_fn)
+  executor = A2aAgentExecutor(runner=runner, config=config)
+  app = Starlette()
+  _compat.attach_a2a_routes_to_app(
+      app,
+      agent_card=agent_card,
+      agent_executor=executor,
+      task_store=TaskStore(),
+  )
+  return app