app.py

# gradio imports
import gradio as gr
import os
import time

# Imports
import os

import openai
from langchain.chains import ConversationalRetrievalChain

from langchain.embeddings.openai import OpenAIEmbeddings
from langchain.document_loaders import TextLoader
from langchain.text_splitter import MarkdownTextSplitter
# from langchain.chat_models import ChatOpenAI
# from langchain.text_splitter import CharacterTextSplitter
from langchain.vectorstores import Chroma
# from langchain.document_loaders import TextLoader

# from langchain.memory import ConversationBufferMemory
# from langchain.chat_models import ChatOpenAI
from langchain.chains.router import MultiRetrievalQAChain
from langchain.llms import OpenAI

css="""
#col-container {max-width: 700px; margin-left: auto; margin-right: auto;}
"""

title = """
<div style="text-align: center;max-width: 700px;">
    <h1>Chat about Bulevar's Menu</h1>
</div>
"""

prompt_hints = """
<div style="text-align: center;max-width: 700px;">
    <p style="text-align: left;">What is in the crab tostada?<br />
</div>
"""

# from index import PERSIST_DIRECTORY, CalendarIndex
REST_PERSIST_DIRECTORY = "chromadb_bul_details"
FOOD_GUIDE_PERSIST_DIRECTORY = "chromadb_food_guide"
# Create embeddings

# # create memory object
# from langchain.memory import ConversationBufferMemory
# memory = ConversationBufferMemory(memory_key="chat_history", return_messages=True)

def loading_pdf():
    return "Loading..."

def loading_database(open_ai_key):
    if open_ai_key is not None:
        os.environ['OPENAI_API_KEY'] = open_ai_key
        openai.api_key = open_ai_key
        
        embeddings = OpenAIEmbeddings(openai_api_key=open_ai_key)
        # adds these restuarant details setnences
        bulevar_restaurant_texts = [
            "Bulevar is open Sunday through Wednesday from 5-9pm, and Thursday through Saturday from 4-10pm. It is open for lunch on Friday from 11-3pm",
            "Bulevar is located in the Arboretum at 360 and Mopac, next to Eddie V's",
            "Bulevar offers tasty Mexican Cuisine with a laid back style to fine-dining.",
            "Bulevar is another restaurant created by Guy and Larry. With the success of their ATX Cocina, Bulevar has created another unique dining experience with high quality dishes."
        ]
        bulevar_details_retriever = Chroma.from_texts(bulevar_restaurant_texts, embeddings, persist_directory=REST_PERSIST_DIRECTORY) #, embedding_function= embeddings
        if not os.path.exists(REST_PERSIST_DIRECTORY):
            save_dir(bulevar_details_retriever)
        loader = TextLoader('raw_text/food_guide.md')
        documents = loader.load()

        # adds the food_guide database
        text_splitter = MarkdownTextSplitter(chunk_size=1000, chunk_overlap=0)
        docs = text_splitter.split_documents(documents)

        docs_retriever = Chroma.from_documents(docs, embeddings, persist_directory=FOOD_GUIDE_PERSIST_DIRECTORY)
        
        if not os.path.exists(FOOD_GUIDE_PERSIST_DIRECTORY):
            save_dir(docs_retriever)
        retriever_infos = [
            {
                "name": "Food Guide", 
                "description": "Good for answering questions about the menu", 
                "retriever": docs_retriever.as_retriever()
            },
            {
                "name": "Bulevar Restaurant Details", 
                "description": "Good for answering questions about Bulevar's hours, and restaurant details such as its mission, history, and owners.", 
                "retriever": bulevar_details_retriever.as_retriever()
            }
        ]
        global chain
        chain = MultiRetrievalQAChain.from_retrievers(OpenAI(temperature=0, openai_api_key=open_ai_key), retriever_infos, verbose=True)
        return "Ready"
    else:
        return "You forgot OpenAI API key"

def save_dir(vectorstore_retriever):
    vectorstore_retriever.persist()

def add_text(history, text):
    history = history + [(text, None)]
    return history, ""


def bot(history):
    response = infer(history[-1][0], history)
    history[-1][1] = ""
    for character in response:     
        history[-1][1] += character
        time.sleep(0.05)
        yield history
    

def infer(question, history):
    # print("Here")
    # print(question)
    # print(history)
    # print("DISPLAYED!!!")
    res = []
    # for human, ai in history[:-1]:
    #     pair = (human, ai)
    #     res.append(pair)
    # print("now ask something new")
    chat_history = res
    query = question
    result = chain({"input": query})
    return result["result"]

def update_message(question_component, chat_prompts):
    question_component.value = chat_prompts.get_name()
    return None

with gr.Blocks(css=css) as demo:
    with gr.Column(elem_id="col-container"):
        gr.HTML(title)
        with gr.Column():
            with gr.Row():
                openai_key = gr.Textbox(label="OpenAI API key", type="password")
                submit_api_key = gr.Button("Submit")
            with gr.Row():
                langchain_status = gr.Textbox(label="Status", placeholder="", interactive=False)
        
        chatbot = gr.Chatbot([], elem_id="chatbot").style(height=350)
        question = gr.Textbox(label="Question", placeholder="Type your question and hit Enter ")
        submit_btn = gr.Button("Send Message")
        gr.HTML(prompt_hints)
        
    submit_api_key.click(loading_database, inputs=[openai_key], outputs=[langchain_status], queue=False)
    # demo.load(loading_database, None, langchain_status)
    question.submit(add_text, [chatbot, question], [chatbot, question]).then(
        bot, chatbot, chatbot
    )
    submit_btn.click(add_text, [chatbot, question], [chatbot, question]).then(
        bot, chatbot, chatbot)

demo.queue(concurrency_count=2, max_size=20).launch()