app.py

import spaces

from transformers import AutoTokenizer, AutoModelForCausalLM
import pandas as pd
import torch
import pprint
import json
import gradio as gr



# Read and preprocess data
TURN_TEMPLATE = "<|im_start|>{role}\n{content}<eos>\n"
TURN_PREFIX = "<|im_start|>{role}\n"

start_token = "<|im_start|>"
end_token = "<eos>"


zero = torch.Tensor([0]).cuda()
print(zero.device) # <-- 'cpu' 🤔

# Load your fine-tuned model and tokenizer
surMuy_model_id = "AingHongsin/SurMuy_v1_512512201"
model = AutoModelForCausalLM.from_pretrained(surMuy_model_id,
                                    device_map={'': 0},
                                    revision="main",
                                    torch_dtype=torch.bfloat16,
                                    )  

tokenizer = AutoTokenizer.from_pretrained(surMuy_model_id)


model.eval()
model.to(zero.device)

def deFormat(data):
    
    # Find the start and end indices of each turn in the data
    turn_indices = []
    start_index = data.find(start_token)
    while start_index != -1:
        end_index = data.find(end_token, start_index)
        if end_index != -1:
            turn_indices.append((start_index, end_index + len(end_token)))
        else:
            turn_indices.append((start_index, len(data)))
        start_index = data.find(start_token, start_index + len(start_token))
    
    # Extract role and content for each turn
    turns = []
    for i in range(len(turn_indices)):
        turn_start, turn_end = turn_indices[i]
        turn_data = data[turn_start:turn_end].strip()
    
        # Extract role and content from turn data using TURN_TEMPLATE
        role_start = len(start_token)
        role_end = turn_data.find("\n", role_start)
        role = turn_data[role_start:role_end]
    
        content_start = role_end + 1
        content = turn_data[content_start:]
    
        turns.append({'role': role, 'content': content})
        
    return turns

@spaces.GPU
def generate(text):
    device = zero.device

    messages = [
        {"role": "user", "content": text}
    ]

    encodeds = tokenizer.apply_chat_template(messages, return_tensors="pt", add_generation_prompt=True)
    # print(tokenizer.convert_ids_to_tokens(encodeds[0]))

    model_inputs = encodeds.to(device)
    model.to(device)

    generated_ids = model.generate(model_inputs, max_new_tokens=512, do_sample=True, pad_token_id=tokenizer.pad_token_id)
    decoded = tokenizer.batch_decode(generated_ids, skip_special_tokens=True)
    predict_answer = deFormat(decoded[0]) 
    return predict_answer

@spaces.GPU
def beam_search(model, start_token, beam_width=3, max_length=10):
    sequences = [[start_token, 0.0]]  # Initialize with start_token and score 0.0

    while len(sequences[0][0]) < max_length:
        all_candidates = []
        for seq, score in sequences:
            if seq[-1] == '<end>':  # Assuming '<end>' is the end token
                all_candidates.append((seq, score))
                continue
            next_token_probs = model.predict_next(seq)
            for token, prob in enumerate(next_token_probs):
                candidate = (seq + [token], score - np.log(prob))
                all_candidates.append(candidate)

        # Order all candidates by score
        ordered = sorted(all_candidates, key=lambda tup: tup[1])
        
        # Select k best
        sequences = ordered[:beam_width]

    return sequences

@spaces.GPU
def beam_search_generate(text, beam_width=8, max_length=512):
    device = "cuda" if torch.cuda.is_available() else "cpu"

    
    messages = []
    
    messages.append(
        {
            "role": "user", "content": text
        }
    )
    
    encodeds = tokenizer.apply_chat_template(messages, return_tensors="pt", add_generation_prompt=True)
    model_inputs = encodeds.to(device)
    model.to(device)
    
    generated_ids = model.generate(
        model_inputs,
        max_new_tokens=max_length,
        num_beams=beam_width,
        early_stopping=True,
        pad_token_id=tokenizer.pad_token_id
    )
    decoded = tokenizer.batch_decode(generated_ids, skip_special_tokens=True)
    predict_object = deFormat(decoded[0])

    messages.append(
        {
            "role": "assistent", "content": ''.join(predict_object[1]['content'])
        }
    )
    return ''.join(predict_object[1]['content'])


def yes_man(message, history):
    return beam_search_generate(message)

gr.ChatInterface(
    yes_man,
    chatbot=gr.Chatbot(height=650),
    textbox=gr.Textbox(placeholder="Write your message here ", container=False, scale=7),
    # slider=gr.Slider(minimum=6, maximum=8, step=1, label="Beam Width"),
    title="Sur Muy",
    description="I am your assistant",
    # examples=["Hello", "Am I cool?", "Are tomatoes vegetables?"],
    cache_examples=True,
    undo_btn="Delete Previous",
    clear_btn="Clear",
).launch()