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gangyan/langchain-chat/server/chat/report_chat.py

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from fastapi import Body, Request
from sse_starlette.sse import EventSourceResponse
from fastapi.concurrency import run_in_threadpool
from configs import (LLM_MODELS,
VECTOR_SEARCH_TOP_K,
SCORE_THRESHOLD,
TEMPERATURE,
USE_RERANKER,
RERANKER_MODEL,
RERANKER_MAX_LENGTH,
MODEL_PATH,
MAX_TOKENS,
MAX_CUT_TOKENS)
from server.utils import wrap_done, get_ChatOpenAI
from server.utils import BaseResponse, get_prompt_template, get_format_template
from server.utils import get_strategy_prompt_template
from langchain.chains import LLMChain
from langchain.callbacks import AsyncIteratorCallbackHandler
from typing import AsyncIterable, List, Optional
import asyncio
from langchain.prompts.chat import ChatPromptTemplate
from server.chat.utils import History
from server.knowledge_base.kb_service.base import KBServiceFactory
import json
from urllib.parse import urlencode
from server.knowledge_base.kb_doc_api import search_docs
from server.reranker.reranker import LangchainReranker
from server.utils import embedding_device
from server.chat.policy_fun import add_summary_retrieved_results, get_llm_model_response
import json
async def report_chat(query: str = Body(..., description="用户输入", examples=["你好"]),
fileName: List = Body([], description="文件名称", examples=[[]]),
knowledge_base_name: str = Body(..., description="知识库名称",
examples=["t_strategy_report_bge_v1"]),
top_k: int = Body(VECTOR_SEARCH_TOP_K, description="匹配向量数"),
score_threshold: float = Body(
SCORE_THRESHOLD,
description="知识库匹配相关度阈值取值范围在0-1之间SCORE越小相关度越高取到1相当于不筛选建议设置在0.5左右",
ge=0,
le=2
),
history: List[History] = Body(
[],
description="历史对话",
examples=[[]]
),
stream: bool = Body(False, description="流式输出"),
model_name: str = Body(LLM_MODELS[0], description="LLM 模型名称。"),
temperature: float = Body(TEMPERATURE, description="LLM 采样温度", ge=0.0, le=1.0),
max_tokens: Optional[int] = Body(
MAX_TOKENS,
description="限制LLM生成Token数量默认None代表模型最大值"
),
prompt_name: str = Body(
"default",
description="使用的prompt模板名称(在configs/prompt_config.py中配置)"
),
request: Request = None,
use_summary = True,
chunk_size: int = 20000,
min_chunk_size: int = 2000,
summary_model_name = LLM_MODELS[0],
query_rewrite_model_name = LLM_MODELS[0]
):
kb = KBServiceFactory.get_service_by_name(knowledge_base_name)
if kb is None:
return BaseResponse(code=404, msg=f"未找到知识库 {knowledge_base_name}")
history = [History.from_data(h) for h in history]
async def knowledge_base_chat_iterator(
query: str,
top_k: int,
history: Optional[List[History]],
model_name: str = model_name,
prompt_name: str = prompt_name,
) -> AsyncIterable[str]:
nonlocal max_tokens
callback = AsyncIteratorCallbackHandler()
if isinstance(max_tokens, int) and max_tokens <= 0:
max_tokens = None
model = get_ChatOpenAI(
model_name=model_name,
temperature=temperature,
max_tokens=max_tokens,
callbacks=[callback],
)
# print('-------------- debug', query)
search_query = get_llm_model_response(
strategy_name="query rewrite",
llm_model_name=query_rewrite_model_name,
template_prompt_name="query_rewrite_report",
prompt_param_dict={"query": query},
temperature=0.01,
max_tokens=512
)
# print('search query', search_query)
json_string = search_query.strip("```json\n").strip("```")
# print('search query----json string', json_string)
try: # 防止json格式错误
# 读取改写后的query
data = json.loads(json_string)
policies = data['report']
search_query = ''
for policy in policies:
search_query += policy
except:
search_query = query
print('search query', search_query)
docs = await run_in_threadpool(search_docs,
fileName=fileName,
query=search_query,
knowledge_base_name=knowledge_base_name,
top_k=top_k,
score_threshold=score_threshold)
# print(docs)
# doc加入metadata的summary字段
if use_summary:
docs = await add_summary_retrieved_results(docs, query, 512,chunk_size,min_chunk_size,summary_model_name)
print(docs)
# context = "\n".join([doc.page_content for doc in docs])
# 需要规范格式的prompt_name
# 默认default即为空不用管
format_list = ["Abstract Assistant", "Outline Assistant"]
if prompt_name in format_list:
format_template = get_format_template("knowledge_base_chat", "abstract_format")
else:
format_template = get_format_template("knowledge_base_chat", "default")
# 政策知识库
# 相关信息把标题和内容进行整合
if knowledge_base_name == 't_strategy_report_bge_v1':
knowledge = []
newdocs =[]
for inum,doc in enumerate(docs):
if use_summary :
if len(doc.metadata['summary'])>15:
knowledge.append(f"""参考报告[{len(knowledge) + 1}] 报告来源: {doc.metadata['source']} \n报告内容: {doc.metadata['summary']}""")
newdocs.append(doc)
else:
pass
else:
knowledge.append(f"""参考报告[{inum + 1}] 报告来源: {doc.metadata['source']} \n报告内容: {doc.page_content}""")
context = "\n\n".join(knowledge)
docs = newdocs
# 非报告知识库
else:
context = "\n".join([doc.page_content for doc in docs])
if len(docs) == 0 and fileName: # 如果没有找到相关文档使用empty模板
prompt_template = get_prompt_template("knowledge_base_chat", prompt_name)
elif len(docs) == 0 and not fileName and prompt_name != "Abstract Assistant":
prompt_template = get_prompt_template("knowledge_base_chat", "empty")
elif prompt_name == 'iast_report_chat' or (knowledge_base_name == "t_strategy_report_bge_v1" and prompt_name == 'default'):
print("use report prompt_template")
prompt_template = get_strategy_prompt_template("knowledge_base_chat", 'iast_report_chat')
else:
prompt_template = get_prompt_template("knowledge_base_chat", prompt_name)
print("prompt_template", prompt_template)
input_msg = History(role="user", content=prompt_template).to_msg_template(False)
chat_prompt = ChatPromptTemplate.from_messages(
[i.to_msg_template() for i in history] + [input_msg])
chain = LLMChain(prompt=chat_prompt, llm=model)
print(
f"\n知识库问答开始调用:参数:\nkb:{knowledge_base_name}\nquery:{query}\nhistory:{history}\ncontext:{context}\nfile_name:{fileName}\nformat_template:{format_template}\n\n")
query = query.replace("原文", "")
task = asyncio.create_task(wrap_done(
chain.acall({"context": context,
"history": history,
"question": query,
"file_name": str(fileName),
"format_template": format_template}),
callback.done),
)
source_documents = []
# 报告知识库
if knowledge_base_name == 't_strategy_report_bge_v1':
for inum, doc in enumerate(docs):
filename = doc.metadata.get("source")
print("filename", filename)
if filename:
text = f"""[{inum + 1}] 报告出处: [{filename}]\n\n{doc.metadata['summary']}\n\n"""
else:
text = f"""[{inum + 1}] \n\n{doc.metadata['summary']}\n\n"""
source_documents.append(text)
# 非报告知识库
else:
for inum, doc in enumerate(docs):
filename = doc.metadata.get("source")
parameters = urlencode({"knowledge_base_name": knowledge_base_name, "file_name": filename})
base_url = request.base_url
url = f"{base_url}knowledge_base/download_doc?" + parameters
if filename:
text = f"""出处: [{filename}]({url}) \n\n"""
else:
text = f"""出处: [{"原文地址"}]({url}) \n\n"""
source_documents.append(text)
if len(source_documents) == 0: # 没有找到相关文档
source_documents.append(f"<span style='color:red'>未找到相关文档,该回答为大模型自身能力解答!</span>")
if stream:
async for token in callback.aiter():
# Use server-sent-events to stream the response
yield json.dumps({"answer": token}, ensure_ascii=False)
else:
answer = ""
async for token in callback.aiter():
answer += token
yield json.dumps({"answer": answer})
await task
yield json.dumps({"docs": source_documents}, ensure_ascii=False)
return EventSourceResponse(knowledge_base_chat_iterator(query, top_k, history, model_name, prompt_name))