app.py

import utils
import streamlit as st
from transformers import AutoModelForCausalLM, AutoTokenizer
from pydantic import BaseModel, validator

from langchain.agents import AgentType, Tool, initialize_agent
from langchain.chat_models import ChatHuggingFace
from langchain.tools import DuckDuckGoSearchRun
from langchain.callbacks import StreamlitCallbackHandler

st.set_page_config(page_title="ChatWeb", page_icon="🌐")
st.header('Chatbot with Internet Access')
st.write('Equipped with internet access, enables users to ask questions about recent events')

class ChatbotTools:

    def __init__(self):
        self.model_name = "mistralai/Mixtral-8x7B-Instruct-v0.1"
        self.tokenizer = AutoTokenizer.from_pretrained(self.model_name)
        self.model = AutoModelForCausalLM.from_pretrained(self.model_name)

    def setup_agent(self):
        # Define tool
        ddg_search = DuckDuckGoSearchRun()
        tools = [
            Tool(
                name="DuckDuckGoSearch",
                func=ddg_search.run,
                description="Useful for when you need to answer questions about current events. You should ask targeted questions",
            )
        ]

        # Setup LLM and Agent
        llm = ChatHuggingFace(model=self.model, tokenizer=self.tokenizer, streaming=True)
        agent = initialize_agent(
            tools=tools,
            llm=llm,
            agent=AgentType.ZERO_SHOT_REACT_DESCRIPTION,
            handle_parsing_errors=True,
            verbose=True
        )
        return agent

    @staticmethod
    def enable_chat_history(func):
        return func

    def main(self):
        agent = self.setup_agent()
        user_query = st.text_input("Ask me anything!")
        if user_query:
            with st.container():
                utils.display_msg(user_query, 'user')
                st_cb = StreamlitCallbackHandler(st.container())
                response = agent.run(user_query, callbacks=[st_cb])
                st.session_state.messages.append({"role": "assistant", "content": response})
                st.write(response)

if __name__ == "__main__":
    obj = ChatbotTools()
    obj.main()