app.py

import gradio as gr

from queue import Queue
from threading import Thread
from callbacks import StreamingGradioCallbackHandler, job_done

from langchain.chat_models import ChatOpenAI
from langchain.chains import ConversationChain
from langchain.memory import ConversationBufferMemory

# huggingface.co/spaces/huggingface-projects/llama-2-13b-chat
DEFAULT_SYSTEM_PROMPT = """\
You are a helpful, respectful and honest assistant. Always answer as helpfully as possible, while being safe.  \
Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please \
ensure that your responses are socially unbiased and positive in nature.\n\nIf a question does not make any sense, or \
is not factually coherent, explain why instead of answering something not correct. If you don't know the answer \
to a question, please don't share false information."""

def respond(openai_api_key, openai_model, creativity, max_tokens, message, buffer_memory, chat_history):
    if openai_api_key == "":
        gr.Warning('Kindly enter a valid OPENAI API key!')
        return message, buffer_memory, chat_history
    
    q = Queue()
    conversation = ConversationChain(
        llm = ChatOpenAI(
            streaming=True,
            model=openai_model,
            max_tokens=max_tokens,
            temperature=creativity,
            openai_api_key=openai_api_key,
            callbacks=[StreamingGradioCallbackHandler(q)]
        ), 
        memory = buffer_memory
    )
    chat_history.append([message, ""])

    thread = Thread(target=conversation.predict, kwargs={
        "input": message,
    })
    thread.start()

    while True:
        next_token = q.get(block=True) # Blocks until an input is available
        if next_token is job_done:
            break
        chat_history[-1] = (chat_history[-1][0], chat_history[-1][1] + next_token)
        yield "", buffer_memory, chat_history  # Yield the chatbot's response
    thread.join()


def init_buffer_memory():
    memory = ConversationBufferMemory()
    memory.save_context({"input": DEFAULT_SYSTEM_PROMPT}, {"output": "Of course!"})
    return memory


def clear():
    return init_buffer_memory(), []


def regenerate_response():
    # TODO: Add functionality
    pass


complete_memory = ConversationBufferMemory()
complete_memory.save_context({"input": DEFAULT_SYSTEM_PROMPT}, {"output": "Of course!"})
with gr.Blocks(css="""
               #component-0 { max-width: 900px; margin: auto; padding-top: 1.5rem; }
               #duplicate-button { margin: auto; color: white; background: #1565c0; border-radius: 100vh; }
               """) as demo:
    gr.Markdown(
        """
        ![](https://huggingface.co/spaces/abdullahmeda/OpenChat/resolve/main/banner.png)

        This Huggingface Gradio Space provides you access to all OpenAI API model that are readily available to 
        the public with custom System Messages. Please note that you would be needing an OPENAI API key to 
        successfully use this space.
        """
    )
    gr.DuplicateButton(value="Duplicate Space for private use", elem_id="duplicate-button")
    
    with gr.Group():
        with gr.Row(visible=True) as primary_settings:
            openai_key = gr.Textbox(
                container=False,
                type="password",
                placeholder="OpenAI Key: sk-a83jv6fn3x8ndm78b5W...",
            )
            model = gr.Dropdown(
                ["gpt-4", "gpt-4-1106-preview",
                "gpt-3.5-turbo", "gpt-3.5-turbo-16k", "gpt-3.5-turbo-instruct", 
                "text-davinci-002", "text-davinci-003"],
                container=False,
                value="gpt-3.5-turbo",
                interactive=True
            )
        
    with gr.Group() as chat:
        memory = gr.State(complete_memory)
        chatbot = gr.Chatbot(label='Chatbot')
        with gr.Row():
            query = gr.Textbox(
                container=False,
                show_label=False,
                placeholder='Type a message...',
                scale=10,
            )
            submit = gr.Button(
                'Submit',
                variant='primary',
                scale=1,
                min_width=0
            )

    with gr.Row():
        regenerate = gr.Button("Regenerate")
        clear_history = gr.Button("Clear History")

    with gr.Accordion(label='Advanced options', open=False):
        system_prompt = gr.Textbox(label='System prompt', value=DEFAULT_SYSTEM_PROMPT, lines=6)
        max_new_tokens = gr.Slider(
            label='Max new tokens',
            minimum=1,
            maximum=4096,
            step=1,
            value=4096,
        )
        temperature = gr.Slider(
            label='Temperature',
            minimum=0.0,
            maximum=1.0,
            step=0.1,
            value=0.0,
        )
        # memory_window = gr.Slider(
        #     label='Converstaion Memory Window',
        #     minimum=-1,
        #     maximum=10,
        #     step=1,
        #     value=-1,
        #     interactive=True
        # )

    # Event Handling
    query.submit(respond, [openai_key, model, temperature, max_new_tokens, query, memory, chatbot], [query, memory, chatbot])
    submit.click(respond, [openai_key, model, temperature, max_new_tokens, query, memory, chatbot], [query, memory, chatbot])

    regenerate.click(regenerate_response, None, None)
    clear_history.click(clear, None, [memory, chatbot])
    
demo.queue().launch()