RegBot4.0 / models /llamaCustom.py
zhtet's picture
Update models/llamaCustom.py
6db6d08
raw
history blame
4.35 kB
import os
import pickle
from json import dumps, loads
from typing import Any, List, Mapping, Optional
import numpy as np
import openai
import pandas as pd
import streamlit as st
from dotenv import load_dotenv
from huggingface_hub import HfFileSystem
from langchain.llms.base import LLM
from llama_index import (
Document,
GPTVectorStoreIndex,
LLMPredictor,
PromptHelper,
ServiceContext,
SimpleDirectoryReader,
StorageContext,
load_index_from_storage,
)
from llama_index.llms import CompletionResponse, CustomLLM, LLMMetadata
from transformers import AutoModelForCausalLM, AutoTokenizer, pipeline
load_dotenv()
# openai.api_key = os.getenv("OPENAI_API_KEY")
fs = HfFileSystem()
# define prompt helper
# set maximum input size
CONTEXT_WINDOW = 2048
# set number of output tokens
NUM_OUTPUT = 525
# set maximum chunk overlap
CHUNK_OVERLAP_RATION = 0.2
@st.cache_resource
def load_model(model_name: str):
# llm_model_name = "bigscience/bloom-560m"
tokenizer = AutoTokenizer.from_pretrained(model_name)
model = AutoModelForCausalLM.from_pretrained(model_name, config="T5Config")
pipe = pipeline(
task="text-generation",
model=model,
tokenizer=tokenizer,
# device=0, # GPU device number
# max_length=512,
do_sample=True,
top_p=0.95,
top_k=50,
temperature=0.7,
)
return pipe
class OurLLM(CustomLLM):
def __init__(self, model_name: str, model_pipeline):
self.model_name = model_name
self.pipeline = model_pipeline
@property
def metadata(self) -> LLMMetadata:
"""Get LLM metadata."""
return LLMMetadata(
context_window=CONTEXT_WINDOW,
num_output=NUM_OUTPUT,
model_name=self.model_name,
)
def complete(self, prompt: str, **kwargs: Any) -> CompletionResponse:
prompt_length = len(prompt)
response = self.pipeline(prompt, max_new_tokens=NUM_OUTPUT)[0]["generated_text"]
# only return newly generated tokens
text = response[prompt_length:]
return CompletionResponse(text=text)
def stream_complete(self, prompt: str, **kwargs: Any) -> CompletionResponse:
raise NotImplementedError()
class LlamaCustom:
def __init__(self, model_name: str) -> None:
self.vector_index = self.initialize_index(model_name=model_name)
def initialize_index(self, model_name: str):
index_name = model_name.split("/")[-1]
file_path = f"./vectorStores/{index_name}"
if os.path.exists(path=file_path):
# rebuild storage context
storage_context = StorageContext.from_defaults(persist_dir=file_path)
# local load index access
index = load_index_from_storage(storage_context)
# huggingface repo load access
# with fs.open(file_path, "r") as file:
# index = pickle.loads(file.readlines())
return index
else:
prompt_helper = PromptHelper(
context_window=CONTEXT_WINDOW,
num_output=NUM_OUTPUT,
chunk_overlap_ratio=CHUNK_OVERLAP_RATION,
)
# define llm
pipe = load_model(model_name=model_name)
llm = OurLLM(model_name=model_name, model_pipeline=pipe)
llm_predictor = LLMPredictor(llm=llm)
service_context = ServiceContext.from_defaults(
llm_predictor=llm_predictor, prompt_helper=prompt_helper
)
# documents = prepare_data(r"./assets/regItems.json")
documents = SimpleDirectoryReader(input_dir="./assets/pdf").load_data()
index = GPTVectorStoreIndex.from_documents(
documents, service_context=service_context
)
# local write access
index.storage_context.persist(file_path)
# huggingface repo write access
# with fs.open(file_path, "w") as file:
# file.write(pickle.dumps(index))
return index
def get_response(self, query_str):
print("query_str: ", query_str)
query_engine = self.vector_index.as_query_engine()
response = query_engine.query(query_str)
print("metadata: ", response.metadata)
return str(response)