chore: Creates a sample main.py to demonstrate how to use adk as a library for the workflow agent in docs.

For Issue #573.

PiperOrigin-RevId: 760380509

contributing/samples/workflow_agent_seq/main.py

@@ -0,0 +1,87 @@
+# Copyright 2025 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.
+
+
+import asyncio
+from typing import cast
+
+import agent
+from dotenv import load_dotenv
+from google.adk.cli.utils import logs
+from google.adk.runners import InMemoryRunner
+from google.adk.sessions import Session
+from google.genai import types
+
+load_dotenv(override=True)
+logs.log_to_tmp_folder()
+
+
+async def main():
+  app_name = 'my_app'
+  user_id_1 = 'user1'
+  runner = InMemoryRunner(
+      app_name=app_name,
+      agent=agent.root_agent,
+  )
+
+  async def run_prompt(session: Session, new_message: str) -> Session:
+    content = types.Content(
+        role='user', parts=[types.Part.from_text(text=new_message)]
+    )
+    print('** User says:', content.model_dump(exclude_none=True))
+    async for event in runner.run_async(
+        user_id=user_id_1,
+        session_id=session.id,
+        new_message=content,
+    ):
+      if not event.content or not event.content.parts:
+        continue
+      if event.content.parts[0].text:
+        print(f'** {event.author}: {event.content.parts[0].text}')
+      elif event.content.parts[0].function_call:
+        print(
+            f'** {event.author}: fc /'
+            f' {event.content.parts[0].function_call.name} /'
+            f' {event.content.parts[0].function_call.args}\n'
+        )
+      elif event.content.parts[0].function_response:
+        print(
+            f'** {event.author}: fr /'
+            f' {event.content.parts[0].function_response.name} /'
+            f' {event.content.parts[0].function_response.response}\n'
+        )
+
+    return cast(
+        Session,
+        await runner.session_service.get_session(
+            app_name=app_name, user_id=user_id_1, session_id=session.id
+        ),
+    )
+
+  session_1 = await runner.session_service.create_session(
+      app_name=app_name, user_id=user_id_1
+  )
+
+  print(f'----Session to create memory: {session_1.id} ----------------------')
+  session_1 = await run_prompt(
+      session_1, 'Write a python function to do quicksort.'
+  )
+  session_1 = await run_prompt(
+      session_1, 'Write another python function to do bubble sort.'
+  )
+  print('-------------------------------------------------------------------')
+
+
+if __name__ == '__main__':
+  asyncio.run(main())