Add Google ADK chatbot sample

A multi-turn conversational chatbot under google_adk_agents: one persisted
ADK session across turns, each turn driven by a workflow Update handler that
returns the assistant's reply, plus a no-op update validator.

Author: xumaple

google_adk_agents/README.md

@@ -39,6 +39,7 @@ Each directory contains a complete example with its own README:
 | Scenario | What it shows |
 | --- | --- |
 | [basic](./basic/README.md) | A single ADK agent with `TemporalModel` and one model call — no tools. The minimal end-to-end example. |
+| [chatbot](./chatbot/README.md) | A multi-turn conversation over one persisted ADK session, with each turn driven by a workflow Update handler that returns the assistant's reply. |
 | [tools](./tools/README.md) | A Temporal activity wrapped as an ADK tool with `activity_tool`, so tool calls run as their own activities. |
 | [agent_patterns](./agent_patterns/README.md) | A coordinator `LlmAgent` with `sub_agents`, each a `TemporalModel` with a per-agent activity summary. |
 | [mcp](./mcp/README.md) | A local echo MCP toolset via `TemporalMcpToolSet` / `TemporalMcpToolSetProvider`, running MCP tools as activities. Self-contained, no Node required. |

google_adk_agents/chatbot/README.md

@@ -0,0 +1,43 @@
+# Chatbot — Multi-Turn Conversation via Updates
+
+A no-frills conversational chatbot: an ADK `Agent` whose
+`model=TemporalModel("gemini-2.5-flash")`, driven by an `InMemoryRunner` inside a
+workflow that stays alive across turns. Unlike the [basic](../basic/README.md)
+single-shot sample, one ADK session persists for the life of the workflow, so
+the assistant remembers earlier turns.
+
+Each conversational turn arrives as a Temporal **Update**: the `message` update
+handler feeds the user's text into `runner.run_async` on the persisted session
+and returns the assistant's reply as the update result. The handler has a noop
+validator that accepts every message. Every model turn still runs as its own
+`invoke_model` activity.
+
+Before running, review the [prerequisites in the suite README](../README.md)
+(Temporal dev server, `uv sync --group google-adk`, and
+`export GOOGLE_API_KEY=...`).
+
+## Running
+
+Start the worker in one terminal:
+
+```bash
+uv run python -m google_adk_agents.chatbot.run_worker
+```
+
+Then start the interactive client in another terminal:
+
+```bash
+uv run python -m google_adk_agents.chatbot.run_chatbot_workflow
+```
+
+## What to expect
+
+The client starts the workflow, then reads messages from stdin. Each line is
+sent as an update and the assistant's reply is printed. Enter an empty line or
+`/quit` to end the session, which terminates the workflow.
+
+## In the Temporal UI
+
+Open the workflow `google-adk-agents-chatbot-workflow-id`. In the history you
+will see the workflow stay running to accept updates, with one `invoke_model`
+activity per turn. The workflow itself stays deterministic and replay-safe.

google_adk_agents/chatbot/__init__.py

@@ -0,0 +1,34 @@
+import asyncio
+
+from temporalio.client import Client
+from temporalio.contrib.google_adk_agents import GoogleAdkPlugin
+
+from google_adk_agents.chatbot.workflows.chatbot_workflow import (
+    ChatbotAgentWorkflow,
+)
+
+
+async def main():
+    # @@@SNIPSTART google-adk-agents-chatbot-starter
+    client = await Client.connect("localhost:7233", plugins=[GoogleAdkPlugin()])
+
+    handle = await client.start_workflow(
+        ChatbotAgentWorkflow.run,
+        id="google-adk-agents-chatbot-workflow-id",
+        task_queue="google-adk-agents-chatbot",
+    )
+
+    print('Chat with the assistant. Enter an empty line or "/quit" to exit.')
+    while True:
+        message = input("> ").strip()
+        if not message or message == "/quit":
+            break
+        reply = await handle.execute_update(ChatbotAgentWorkflow.message, message)
+        print(f"Assistant: {reply}")
+
+    await handle.terminate()
+    # @@@SNIPEND
+
+
+if __name__ == "__main__":
+    asyncio.run(main())

google_adk_agents/chatbot/run_chatbot_workflow.py

@@ -0,0 +1,31 @@
+from __future__ import annotations
+
+import asyncio
+
+from temporalio.client import Client
+from temporalio.contrib.google_adk_agents import GoogleAdkPlugin
+from temporalio.worker import Worker
+
+from google_adk_agents.chatbot.workflows.chatbot_workflow import (
+    ChatbotAgentWorkflow,
+)
+
+
+async def main():
+    # @@@SNIPSTART google-adk-agents-chatbot-worker
+    plugin = GoogleAdkPlugin()
+
+    client = await Client.connect("localhost:7233", plugins=[plugin])
+
+    worker = Worker(
+        client,
+        task_queue="google-adk-agents-chatbot",
+        workflows=[ChatbotAgentWorkflow],
+        plugins=[plugin],
+    )
+    await worker.run()
+    # @@@SNIPEND
+
+
+if __name__ == "__main__":
+    asyncio.run(main())

google_adk_agents/chatbot/run_worker.py

@@ -0,0 +1,70 @@
+import asyncio
+
+from google.adk import Agent
+from google.adk.runners import InMemoryRunner
+from google.adk.utils.context_utils import Aclosing
+from google.genai import types
+from temporalio import workflow
+from temporalio.contrib.google_adk_agents import TemporalModel
+
+
+# @@@SNIPSTART google-adk-agents-chatbot-agent-workflow
+@workflow.defn
+class ChatbotAgentWorkflow:
+    def __init__(self) -> None:
+        self._ready = False
+        self._runner: InMemoryRunner | None = None
+        self._session_id: str | None = None
+
+    @workflow.run
+    async def run(self) -> str:
+        agent = Agent(
+            name="chatbot_agent",
+            model=TemporalModel("gemini-2.5-flash"),
+            instruction="You are a helpful assistant.",
+        )
+
+        # The plugin points ADK's session-id generation at workflow.uuid4(), so
+        # creating a session here is replay-safe.
+        self._runner = InMemoryRunner(agent=agent, app_name="chatbot_app")
+        session = await self._runner.session_service.create_session(
+            app_name="chatbot_app", user_id="user"
+        )
+        self._session_id = session.id
+        self._ready = True
+
+        # Block forever to stay alive serving update turns; the client
+        # terminates the workflow when the user quits.
+        return await asyncio.Future()
+
+    @workflow.update
+    async def message(self, message: str) -> str:
+        # An update can arrive before run() has created the runner and session,
+        # so wait until they are ready before using them.
+        await workflow.wait_condition(lambda: self._ready)
+        assert self._runner is not None and self._session_id is not None
+
+        final_text = ""
+        async with Aclosing(
+            self._runner.run_async(
+                user_id="user",
+                session_id=self._session_id,
+                new_message=types.Content(
+                    role="user", parts=[types.Part(text=message)]
+                ),
+            )
+        ) as agen:
+            async for event in agen:
+                if event.content and event.content.parts:
+                    for part in event.content.parts:
+                        if part.text:
+                            final_text = part.text
+
+        return final_text
+
+    @message.validator
+    def validate_message(self, message: str) -> None:
+        pass
+
+
+# @@@SNIPEND

google_adk_agents/chatbot/workflows/__init__.py

@@ -30,6 +30,7 @@ def patch_model(
     responses: list[LlmResponse],
     *,
     stream_chunks: bool = False,
+    captured: list[LlmRequest] | None = None,
 ) -> None:
     script = list(responses)
     orig_new_llm = LLMRegistry.new_llm  # staticmethod
@@ -38,6 +39,8 @@ class _Mock(BaseLlm):
         async def generate_content_async(
             self, llm_request: LlmRequest, stream: bool = False
         ) -> AsyncGenerator[LlmResponse, None]:
+            if captured is not None:
+                captured.append(llm_request)
             if stream_chunks:
                 # The streaming sample is single-turn, so yield every scripted
                 # chunk on this one call.

google_adk_agents/chatbot/workflows/chatbot_workflow.py

@@ -0,0 +1,57 @@
+import uuid
+
+import pytest
+from google.adk.models.llm_request import LlmRequest
+from temporalio.client import Client
+from temporalio.contrib.google_adk_agents import GoogleAdkPlugin
+from temporalio.worker import Worker
+
+from google_adk_agents.chatbot.workflows.chatbot_workflow import (
+    ChatbotAgentWorkflow,
+)
+from tests.google_adk_agents._mock_model import patch_model, text
+
+
+async def test_chatbot(client: Client, monkeypatch: pytest.MonkeyPatch) -> None:
+    captured: list[LlmRequest] = []
+    patch_model(
+        monkeypatch, [text("first reply"), text("second reply")], captured=captured
+    )
+
+    task_queue = f"google-adk-agents-chatbot-{uuid.uuid4()}"
+    plugin = GoogleAdkPlugin()
+
+    config = client.config()
+    config["plugins"] = [*config["plugins"], plugin]
+    client = Client(**config)
+
+    async with Worker(
+        client,
+        task_queue=task_queue,
+        workflows=[ChatbotAgentWorkflow],
+        max_cached_workflows=0,
+    ):
+        handle = await client.start_workflow(
+            ChatbotAgentWorkflow.run,
+            id=f"google-adk-agents-chatbot-{uuid.uuid4()}",
+            task_queue=task_queue,
+        )
+
+        first = await handle.execute_update(ChatbotAgentWorkflow.message, "Hello")
+        second = await handle.execute_update(ChatbotAgentWorkflow.message, "Again")
+
+        await handle.terminate()
+
+    assert first == "first reply"
+    assert second == "second reply"
+
+    # The second turn reuses the same session, so its request carries the first
+    # turn's history.
+    turn_two_history = "\n".join(
+        part.text
+        for content in captured[1].contents
+        for part in (content.parts or [])
+        if part.text
+    )
+    assert "Hello" in turn_two_history
+    assert "first reply" in turn_two_history