app.py

import openai
from langchain.vectorstores import Chroma
from langchain.embeddings import OpenAIEmbeddings
from retriever import *
from chain import *
import gradio as gr

def chatbot(query):
    llm_response = qa_chain.run({"query": query})
    return llm_response


def load_embeddings_database_from_disk(persistence_directory, embeddings_generator):
    """
    Load a Chroma vector database from disk.

    This function loads a Chroma vector database from the specified directory on disk.
    It expects the same persistence_directory and embedding function as used when creating the database.
    
    Args:
        persistence_directory (str): The directory where the database is stored on disk.
        embeddings_generator (obj): The embeddings generator function that was used when creating the database.

    Returns:
        vector_database (obj): The loaded Chroma vector database.
    """

    # Load the Chroma vector database from the persistence directory.
    # The embedding_function parameter should be the same as the one used when the database was created.
    vector_database = Chroma(persist_directory=persistence_directory, embedding_function=embeddings_generator)

    return vector_database


# Specify the directory where the database will be stored when it's persisted.
persistence_directory = 'db'
# Create and persist the embeddings for the documents.
embeddings_generator = OpenAIEmbeddings(openai_api_key = openai.api_key)
# Load the Chroma vector database from disk.
vector_database = load_embeddings_database_from_disk(persistence_directory, embeddings_generator)
topk_documents = 2
# Creating the retriever on top documents.
retriever = initialize_document_retriever(topk_documents, vector_database)
qa_chain = create_question_answering_chain(retriever)


inputs = gr.inputs.Textbox(lines=7, label="Coversational Interface with Chat history")
outputs = gr.outputs.Textbox(label="Reply")

gr.Interface(fn=chatbot, inputs=inputs, outputs=outputs, title="Retrieval Augmented Question Answering",
             show_progress = True, theme="compact").launch(debug=True)