{ "cells": [ { "cell_type": "code", "execution_count": 2, "id": "711d55a7", "metadata": {}, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "根据上下文,员工被辞退时“不支付任何经济补偿金”。\n" ] } ], "source": [ "from langchain_community.document_loaders import Docx2txtLoader\n", "from langchain_text_splitters import RecursiveCharacterTextSplitter\n", "from langchain_community.embeddings import DashScopeEmbeddings\n", "from langchain_community.vectorstores import Chroma\n", "from langchain_core.prompts import ChatPromptTemplate\n", "from langchain_community.chat_models import ChatTongyi\n", "from langchain_core.output_parsers import StrOutputParser\n", "import os\n", "from dotenv import load_dotenv\n", "\n", "load_dotenv()\n", "\n", "qwen_api_key = os.getenv(\"QWEN_API_KEY\")\n", "\n", "# ========== 第一步:加载文档 ==========\n", "loader = Docx2txtLoader(\"./人事管理流程.docx\")\n", "pages = loader.load()\n", "\n", "# ========== 第二步:清洗数据(可选,根据文档质量决定)==========\n", "# clean_pages = [clean_pdf_text(page) for page in pages]\n", "\n", "# ========== 第三步:分块 ==========\n", "splitter = RecursiveCharacterTextSplitter(\n", " # 分隔符优先级:段落 → 换行 → 句号 → 空格 → 硬切\n", " separators=[\"\\n\\n\", \"\\n\", \"。\", \"!\", \"?\", \" \", \"\"],\n", " # 每个块最大 50 字符\n", " chunk_size=50,\n", " # 相邻块重叠 10 字符(chunk_size 的 20%)\n", " chunk_overlap=10,\n", " # 长度计算函数\n", " length_function=len\n", ")\n", "docs = splitter.split_documents(pages)\n", "\n", "# ========== 第四步:向量化 + 存入向量库 ==========\n", "embedding_model = DashScopeEmbeddings(\n", " model=\"text-embedding-v3\",\n", " dashscope_api_key=qwen_api_key\n", ")\n", "vectorstore = Chroma.from_documents(\n", " documents=docs,\n", " embedding=embedding_model,\n", " persist_directory=\"./knowledge_db\"\n", ")\n", "\n", "# ========== 第五步:创建检索器 ==========\n", "retriever = vectorstore.as_retriever(search_kwargs={\"k\": 3})\n", "\n", "# ========== 第六步:提问 ==========\n", "query = \"员工被辞退的补偿有什么?\"\n", "relevant_docs = retriever.invoke(query)\n", "\n", "# ========== 第七步:生成回答 ==========\n", "context = \"\\n\\n---\\n\\n\".join([d.page_content for d in relevant_docs])\n", "\n", "prompt = ChatPromptTemplate.from_template(\"\"\"\n", "你是一个专业的知识库助手。请根据以下上下文回答问题。\n", "\n", "**规则:**\n", "- 只基于提供的上下文回答,不要编造\n", "- 如果上下文中没有相关信息,直接说「根据现有资料,我找不到这个问题的答案」\n", "- 回答要简洁直接,引用原文时用引号\n", "\n", "**上下文:**\n", "{context}\n", "\n", "**问题:**\n", "{question}\n", "\"\"\")\n", "\n", "llm = ChatTongyi(model=\"qwen-plus\", dashscope_api_key=qwen_api_key)\n", "chain = prompt | llm | StrOutputParser()\n", "\n", "answer = chain.invoke({\"context\": context, \"question\": query})\n", "print(answer)" ] } ], "metadata": { "kernelspec": { "display_name": "0701RAG (3.11.x)", "language": "python", "name": "python3" }, "language_info": { "codemirror_mode": { "name": "ipython", "version": 3 }, "file_extension": ".py", "mimetype": "text/x-python", "name": "python", "nbconvert_exporter": "python", "pygments_lexer": "ipython3", "version": "3.11.15" } }, "nbformat": 4, "nbformat_minor": 5 }