app.py

import asyncio

import streamlit as st
from langchain.agents import AgentType
from langchain.agents import initialize_agent
from langchain.chat_models import ChatOpenAI
from langchain.memory import ConversationBufferMemory
from langchain.memory.chat_message_histories import StreamlitChatMessageHistory
from langchain.schema import SystemMessage
from langchain.prompts import MessagesPlaceholder

from app.tools import StoriesTool
from app.tools import CommentsTool
from app.tools import ContentTool


async def generate_response(question):
    result = await open_ai_agent.arun(question)
    return result


st.set_page_config(page_title="NewsNerd HackerBot 🤖📰")
st.title("NewsNerd HackerBot 🤖📰")
stop = False

with st.sidebar:
    if 'OPENAI_API_KEY' in st.secrets:
        st.success("OPENAI_API_KEY already provided!", icon='✅')
        openai_api_key = st.secrets['OPENAI_API_KEY']
    else:
        openai_api_key = st.text_input('Enter your OPENAI_API_KEY: ', type='password')
        if not openai_api_key:
            st.warning('Please, enter your OPENAI_API_KEY', icon='⚠️')
            stop = True
        else:
            st.success('Ask Hacker News whatever you want!', icon='👉')

    st.markdown("""
    # **Greetings, Digital Explorer!**

    Are you fatigued from navigating the expansive digital realm in search of your daily tech tales 
    and hacker happenings? Fear not, for your cyber-savvy companion has descended upon the scene – 
    behold the extraordinary **NewsNerd HackerBot**!
    """)

if stop:
    st.stop()


tools = [StoriesTool(), CommentsTool(), ContentTool()]
msgs = StreamlitChatMessageHistory(key="langchain_messages")
memory = ConversationBufferMemory(chat_memory=msgs, return_messages=True)
system_message = SystemMessage(content="""
You are the Singularity Incarnation of Hacker News.
The human will ask you for information about Hacker News.
If you can't find any information  about the question asked
or the result is incomplete, apologise to the human and ask him if 
you can help him with something else.
If the human asks you to show him stories, do it using a markdown table.
The markdown table has the following format:

story_id | title | url | score
""")

if len(msgs.messages) == 0:
    msgs.add_ai_message("Greetings, human, I am the Incarnation of Hacker News. How can I help you?")

llm = ChatOpenAI(temperature=0, model="gpt-3.5-turbo-0613", openai_api_key=openai_api_key)
agent_kwargs = {
    "system_message": system_message,
    "extra_prompt_messages": [MessagesPlaceholder(variable_name="history")]
}
open_ai_agent = initialize_agent(tools,
                                 llm,
                                 agent=AgentType.OPENAI_FUNCTIONS,
                                 agent_kwargs=agent_kwargs,
                                 verbose=True,
                                 memory=memory
                                 )

for msg in msgs.messages:
    st.chat_message(msg.type).write(msg.content)


if prompt := st.chat_input(disabled=not openai_api_key):
    st.chat_message("human").write(prompt)
    with st.spinner("Thinking ..."):
        response = asyncio.run(generate_response(prompt))
        st.chat_message("ai").write(response)