nicegui/examples/chat_with_ai/main.py

#!/usr/bin/env python3
from typing import List, Tuple

from langchain.chains import ConversationChain
from langchain.chat_models import ChatOpenAI

from nicegui import Client, ui
from log_callback_handler import NiceGuiLogElementCallbackHandler

OPENAI_API_KEY = 'not-set'  # TODO: set your OpenAI API key here

llm = ConversationChain(llm=ChatOpenAI(model_name='gpt-3.5-turbo', openai_api_key=OPENAI_API_KEY))

messages: List[Tuple[str, str]] = []
thinking: bool = False


@ui.refreshable
async def chat_messages() -> None:
    for name, text in messages:
        ui.chat_message(text=text, name=name, sent=name == 'You')
    if thinking:
        ui.spinner(size='3rem').classes('self-center')
    await ui.run_javascript('window.scrollTo(0, document.body.scrollHeight)', respond=False)


@ui.page('/')
async def main(client: Client):

    with ui.tabs().classes('w-full') as tabs:
        chat_panel = ui.tab('Chat')
        logs_panel = ui.tab('Logs')
    with ui.tab_panels(tabs).classes('w-full'):
        with ui.tab_panel(logs_panel):
            log = ui.log().classes('w-full').style('height: 50vh;')

    async def send() -> None:
        global thinking
        message = text.value
        messages.append(('You', text.value))
        thinking = True
        text.value = ''
        chat_messages.refresh()

        response = await llm.arun(message, callbacks=[NiceGuiLogElementCallbackHandler(log)])
        messages.append(('Bot', response))
        thinking = False
        chat_messages.refresh()

    anchor_style = r'a:link, a:visited {color: inherit !important; text-decoration: none; font-weight: 500}'
    ui.add_head_html(f'<style>{anchor_style}</style>')
    await client.connected()
    
    with ui.tab_panels(tabs, value=chat_panel).classes('w-full'):
        with ui.tab_panel(chat_panel):
            with ui.column().classes('w-full max-w-2xl mx-auto items-stretch'):
                await chat_messages()

    with ui.footer().classes('bg-white'), ui.column().classes('w-full max-w-3xl mx-auto my-6'):
        with ui.row().classes('w-full no-wrap items-center'):
            placeholder = 'message' if OPENAI_API_KEY != 'not-set' else \
                'Please provide your OPENAI key in the Python script first!'
            text = ui.input(placeholder=placeholder).props('rounded outlined input-class=mx-3') \
                .classes('w-full self-center').on('keydown.enter', send)
        ui.markdown('simple chat app built with [NiceGUI](https://nicegui.io)') \
            .classes('text-xs self-end mr-8 m-[-1em] text-primary')

ui.run(title='Chat with GPT-3 (example)')