app.py

import datetime
import os
from langchain.chains import VectorDBQAWithSourcesChain
import gradio as gr
import langchain
from langchain.vectorstores import Weaviate
import faiss
import pickle
from langchain import OpenAI
from arxiv import get_paper
from ingest_faiss import create_vector_store

def get_vectorstore(suffix):
    index = faiss.read_index(f"{suffix}/docs.index")
    with open(f"{suffix}/faiss_store.pkl", "rb") as f:
        store = pickle.load(f)
    store.index = index
    return store

def set_openai_api_key(api_key, agent):
    if api_key:
        os.environ["OPENAI_API_KEY"] = api_key
        vectorstore = get_vectorstore()
        qa_chain = VectorDBQAWithSourcesChain.from_llm(llm=OpenAI(temperature=0), vectorstore=vectorstore)
        os.environ["OPENAI_API_KEY"] = ""
        return qa_chain

def download_paper_and_embed(paper_arxiv_url, api_key):
    if paper_arxiv_url and api_key:
        paper_text = get_paper(paper_arxiv_url)
        if 'abs' in paper_arxiv_url:
            eprint_url = paper_arxiv_url.replace("https://arxiv.org/abs/", "https://arxiv.org/e-print/")
        elif 'pdf' in paper_arxiv_url:
            eprint_url = paper_arxiv_url.replace("https://arxiv.org/pdf/", "https://arxiv.org/e-print/")
        else:
            raise ValueError("Invalid arXiv URL")
        suffix = 'paper-dir/' + eprint_url.replace("https://arxiv.org/e-print/", "")
        os.environ["OPENAI_API_KEY"] = api_key
        if not os.path.exists(suffix + "/docs.index"):
            create_vector_store(suffix, paper_text)

        
        vectorstore = get_vectorstore(suffix)
        qa_chain = VectorDBQAWithSourcesChain.from_llm(llm=OpenAI(temperature=0), vectorstore=vectorstore)
        return qa_chain

chain = None

def chat(inp, history, paper_arxiv_url, api_key, agent):
    global chain
    if history is None:
        chain = download_paper_and_embed(paper_arxiv_url, api_key)
    history = history or []
    # if agent is None:
    #     history.append((inp, "Please paste your OpenAI key to use"))
    #     return history, history
    print("\n==== date/time: " + str(datetime.datetime.now()) + " ====")
    print("inp: " + inp)
    history = history or []
    agent = chain
    output = agent({"question": inp})
    answer = output["answer"]
    sources = output["sources"]
    sources = sources.split(", ")
    sources = ", ".join([s.title() for s in sources])
    history.append((inp, answer))
    history.append(("Sources?", sources))
    print(history)
    return history, history

block = gr.Blocks(css=".gradio-container {background-color: lightgray}")

with block:
    state = gr.State()
    agent_state = gr.State()
    with gr.Row():
        gr.Markdown("<h3><center>PaperChat</center></h3>")

        paper_arxiv_url = gr.Textbox(
            placeholder="Paste the URL of the paper about which you want to ask a question",
            show_label=False,
            lines=1,
            type="text",
        )

        openai_api_key_textbox = gr.Textbox(
            placeholder="Paste your OpenAI API key (sk-...)",
            show_label=False,
            lines=1,
            type="password",
        )

        # # button to download paper
        # download_paper_button = gr.Button(
        #     value="Download paper and make embeddings",
        #     variant="secondary",
        # ).click(
        #     download_paper_and_embed,
        #     inputs=[paper_arxiv_url, openai_api_key_textbox, agent_state],
        #     outputs=[agent_state],
        # )

    chatbot = gr.Chatbot()

    with gr.Row():
        message = gr.Textbox(
            label="What's your question?",
            placeholder="What's the answer to life, the universe, and everything?",
            lines=1,
        )
        submit = gr.Button(value="Send", variant="secondary").style(full_width=False)

    # gr.Examples(
    #     examples=[
    #         "What are agents?",
    #         "How do I summarize a long document?",
    #         "What types of memory exist?",
    #     ],
    #     inputs=message,
    # )

    gr.HTML(
        """Ask questions of any arXiv paper and get factual answers with sources"""
    )

    gr.HTML(
        "<center>By <a href='https://twitter.com/0xjasper'>Jasper</a>, powered by <a href='https://github.com/hwchase17/langchain'>LangChain 🦜️🔗</a></center>"
    )

    submit.click(chat, inputs=[message, state, paper_arxiv_url, openai_api_key_textbox, agent_state], outputs=[chatbot, state])
    message.submit(chat, inputs=[message, state, paper_arxiv_url, openai_api_key_textbox, agent_state], outputs=[chatbot, state])

    # paper_arxiv_url.change(
    #     download_paper_and_embed,
    #     inputs=[paper_arxiv_url, agent_state],
    #     outputs=[agent_state],
    # )

    # openai_api_key_textbox.change(
    #     set_openai_api_key,
    #     inputs=[openai_api_key_textbox, agent_state],
    #     outputs=[agent_state],
    # )

block.launch(debug=True)