基于 InternLM 和 LangChain 搭建你的知识库
# 首先导入所需第三方库
from langchain.document_loaders import UnstructuredFileLoader
from langchain.document_loaders import UnstructuredMarkdownLoader
from langchain.text_splitter import RecursiveCharacterTextSplitter
from langchain.vectorstores import Chroma
from langchain.embeddings.huggingface import HuggingFaceEmbeddings
from tqdm import tqdm
import os
# 获取文件路径函数
def get_files(dir_path):
# args：dir_path，目标文件夹路径
file_list = []
for filepath, dirnames, filenames in os.walk(dir_path):
# os.walk 函数将递归遍历指定文件夹
for filename in filenames:
# 通过后缀名判断文件类型是否满足要求
if filename.endswith(".md"):
# 如果满足要求，将其绝对路径加入到结果列表
file_list.append(os.path.join(filepath, filename))
elif filename.endswith(".txt"):
file_list.append(os.path.join(filepath, filename))
return file_list
# 加载文件函数
def get_text(dir_path):
# args：dir_path，目标文件夹路径
# 首先调用上文定义的函数得到目标文件路径列表
file_lst = get_files(dir_path)
# docs 存放加载之后的纯文本对象
docs = []
# 遍历所有目标文件
for one_file in tqdm(file_lst):
file_type = one_file.split('.')[-1]
if file_type == 'md':
loader = UnstructuredMarkdownLoader(one_file)
elif file_type == 'txt':
loader = UnstructuredFileLoader(one_file)
else:
# 如果是不符合条件的文件，直接跳过
continue
docs.extend(loader.load())
return docs
# 目标文件夹
tar_dir = [
"/root/data/InternLM",
"/root/data/InternLM-XComposer",
"/root/data/lagent",
"/root/data/lmdeploy",
"/root/data/opencompass",
"/root/data/xtuner",
"/root/data/interview"
]
# 加载目标文件
docs = []
for dir_path in tar_dir:
docs.extend(get_text(dir_path))
# 对文本进行分块
text_splitter = RecursiveCharacterTextSplitter(
chunk_size=500, chunk_overlap=150)
split_docs = text_splitter.split_documents(docs)
# 加载开源词向量模型
embeddings = HuggingFaceEmbeddings(model_name="/root/data/model/sentence-transformer")
# 构建向量数据库
# 定义持久化路径
persist_directory = 'data_base/vector_db/chroma'
# 加载数据库
vectordb = Chroma.from_documents(
documents=split_docs,
embedding=embeddings,
persist_directory=persist_directory # 允许我们将persist_directory目录保存到磁盘上
)
# 将加载的向量数据库持久化到磁盘上
vectordb.persist()
from langchain.llms.base import LLM
from typing import Any, List, Optional
from langchain.callbacks.manager import CallbackManagerForLLMRun
from transformers import AutoTokenizer, AutoModelForCausalLM
import torch
class InternLM_LLM(LLM):
# 基于本地 InternLM 自定义 LLM 类
tokenizer : AutoTokenizer = None
model: AutoModelForCausalLM = None
def __init__(self, model_path :str):
# model_path: InternLM 模型路径
# 从本地初始化模型
super().__init__()
print("正在从本地加载模型...")
self.tokenizer = AutoTokenizer.from_pretrained(model_path, trust_remote_code=True)
self.model = AutoModelForCausalLM.from_pretrained(model_path, trust_remote_code=True).to(torch.bfloat16).cuda()
self.model = self.model.eval()
print("完成本地模型的加载")
def _call(self, prompt : str, stop: Optional[List[str]] = None,
run_manager: Optional[CallbackManagerForLLMRun] = None,
**kwargs: Any):
# 重写调用函数
system_prompt = """You are an AI assistant whose name is InternLM (书生·浦语).
- InternLM (书生·浦语) is a conversational language model that is developed by Shanghai AI Laboratory (上海人工智能实验室). It is designed to be helpful, honest, and harmless.
- InternLM (书生·浦语) can understand and communicate fluently in the language chosen by the user such as English and 中文.
"""
messages = [(system_prompt, '')]
response, history = self.model.chat(self.tokenizer, prompt , history=messages)
return response
@property
def _llm_type(self) -> str:
return "InternLM"
from langchain.vectorstores import Chroma
from langchain.embeddings.huggingface import HuggingFaceEmbeddings
import os
from LLM import InternLM_LLM
from langchain.prompts import PromptTemplate
from langchain.chains import RetrievalQA
def load_chain():
# 加载问答链
# 定义 Embeddings
embeddings = HuggingFaceEmbeddings(model_name="/root/data/model/sentence-transformer")
# 向量数据库持久化路径
persist_directory = 'data_base/vector_db/chroma'
# 加载数据库
vectordb = Chroma(
persist_directory=persist_directory, # 允许我们将persist_directory目录保存到磁盘上
embedding_function=embeddings
)
# 加载自定义 LLM
llm = InternLM_LLM(model_path = "/root/data/model/Shanghai_AI_Laboratory/internlm-chat-7b")
# 定义一个 Prompt Template
template = """使用以下上下文来回答最后的问题。如果你不知道答案，就说你不知道，不要试图编造答
案。尽量使答案简明扼要。总是在回答的最后说“谢谢你的提问！”。
{context}
问题: {question}
有用的回答:"""
QA_CHAIN_PROMPT = PromptTemplate(input_variables=["context","question"],template=template)
# 运行 chain
qa_chain = RetrievalQA.from_chain_type(llm,retriever=vectordb.as_retriever(),return_source_documents=True,chain_type_kwargs={"prompt":QA_CHAIN_PROMPT})
return qa_chain
class Model_center():
"""
存储检索问答链的对象
"""
def __init__(self):
# 构造函数，加载检索问答链
self.chain = load_chain()
def qa_chain_self_answer(self, question: str, chat_history: list = []):
"""
调用问答链进行回答
"""
if question == None or len(question) < 1:
return "", chat_history
try:
chat_history.append(
(question, self.chain({"query": question})["result"]))
# 将问答结果直接附加到问答历史中，Gradio 会将其展示出来
return "", chat_history
except Exception as e:
return e, chat_history
import gradio as gr
# 实例化核心功能对象
model_center = Model_center()
# 创建一个 Web 界面
block = gr.Blocks()
with block as demo:
with gr.Row(equal_height=True):
with gr.Column(scale=15):
# 展示的页面标题
gr.Markdown("""<h1><center>InternLM</center></h1>
<center>书生浦语</center>
""")
with gr.Row():
with gr.Column(scale=4):
# 创建一个聊天机器人对象
chatbot = gr.Chatbot(height=450, show_copy_button=True)
# 创建一个文本框组件，用于输入 prompt。
msg = gr.Textbox(label="Prompt/问题")
with gr.Row():
# 创建提交按钮。
db_wo_his_btn = gr.Button("Chat")
with gr.Row():
# 创建一个清除按钮，用于清除聊天机器人组件的内容。
clear = gr.ClearButton(
components=[chatbot], value="Clear console")
# 设置按钮的点击事件。当点击时，调用上面定义的 qa_chain_self_answer 函数，并传入用户的消息和聊天历史记录，然后更新文本框和聊天机器人组件。
db_wo_his_btn.click(model_center.qa_chain_self_answer, inputs=[
msg, chatbot], outputs=[msg, chatbot])
gr.Markdown("""提醒：<br>
1. 初始化数据库时间可能较长，请耐心等待。
2. 使用中如果出现异常，将会在文本输入框进行展示，请不要惊慌。 <br>
""")
gr.close_all()
# 直接启动
demo.launch()
自定义知识库，训练面试八股文AI小助手：
基于 InternLM 和 LangChain 搭建你的知识库
