Shiny Chat with Gemini - "Error in Effect: 400 Please use a valid role: user, model"

[Vergiel-a]

I'm trying to implement a Shiny Chat using the Gemini language model, following the example. The initial interaction with the model works fine, but subsequent interactions result in the error: "Error in Effect: 400 Please use a valid role: user, model".

The error occurs after the first successful interaction with the model. I have included a screenshot of the error message.

Here's the traceback from the terminal:

Traceback (most recent call last):
  File "C:\Users\Dell\AppData\Local\Programs\Python\Python311\Lib\site-packages\shiny\ui\_chat.py", line 322, in handle_user_input
    await afunc()
  File "C:\Users\Dell\Downloads\gemini\app.py", line 38, in _
    response = llm.generate_content(
               ^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\Dell\AppData\Local\Programs\Python\Python311\Lib\site-packages\google\generativeai\generative_models.py", line 325, in generate_content
    iterator = self._client.stream_generate_content(
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\Dell\AppData\Local\Programs\Python\Python311\Lib\site-packages\google\ai\generativelanguage_v1beta\services\generative_service\client.py", line 1122, in stream_generate_content
    response = rpc(
               ^^^^
  File "C:\Users\Dell\AppData\Local\Programs\Python\Python311\Lib\site-packages\google\api_core\gapic_v1\method.py", line 131, in __call__
    return wrapped_func(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\Dell\AppData\Local\Programs\Python\Python311\Lib\site-packages\google\api_core\retry\retry_unary.py", line 293, in retry_wrapped_func
    return retry_target(
           ^^^^^^^^^^^^^
  File "C:\Users\Dell\AppData\Local\Programs\Python\Python311\Lib\site-packages\google\api_core\retry\retry_unary.py", line 153, in retry_target
    _retry_error_helper(
  File "C:\Users\Dell\AppData\Local\Programs\Python\Python311\Lib\site-packages\google\api_core\retry\retry_base.py", line 212, in _retry_error_helper
    raise final_exc from source_exc
  File "C:\Users\Dell\AppData\Local\Programs\Python\Python311\Lib\site-packages\google\api_core\retry\retry_unary.py", line 144, in retry_target
    result = target()
             ^^^^^^^^
  File "C:\Users\Dell\AppData\Local\Programs\Python\Python311\Lib\site-packages\google\api_core\timeout.py", line 120, in func_with_timeout
    return func(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\Dell\AppData\Local\Programs\Python\Python311\Lib\site-packages\google\api_core\grpc_helpers.py", line 174, in error_remapped_callable
    raise exceptions.from_grpc_error(exc) from exc
google.api_core.exceptions.InvalidArgument: 400 Please use a valid role: user, model.

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "C:\Users\Dell\AppData\Local\Programs\Python\Python311\Lib\site-packages\shiny\reactive\_reactives.py", line 584, in _run
    await self._fn()
  File "C:\Users\Dell\AppData\Local\Programs\Python\Python311\Lib\site-packages\shiny\reactive\_reactives.py", line 885, in new_user_async_fn
    return await user_fn()
           ^^^^^^^^^^^^^^^
  File "C:\Users\Dell\AppData\Local\Programs\Python\Python311\Lib\site-packages\shiny\ui\_chat.py", line 324, in handle_user_input
    await self._raise_exception(e)
  File "C:\Users\Dell\AppData\Local\Programs\Python\Python311\Lib\site-packages\shiny\ui\_chat.py", line 344, in _raise_exception
    raise NotifyException(str(e), sanitize=sanitize)
shiny.types.NotifyException: 400 Please use a valid role: user, model.

Could you provide guidance on how to ensure that the correct roles are being assigned or passed during subsequent interactions with the Gemini model?

[cpsievert]

Yikes, thanks for the report, and sorry for the embarrassing error!

This is now fixed via #1622.

If you don't want to install the dev version of Shiny (to get the fix), you could also add the following line immediately after contents = chat.messages(format="google") in that example app, which would also fix the issue

contents = [
    {**x, "role": "model"} if x.get("role") == "assistant" else x
    for x in contents
]