- Created a new Streamlit application for visualizing knowledge graphs. - Implemented text extraction from PDF, Markdown, and TXT files. - Developed graph building logic using Zep Cloud API. - Added support for custom entity types and relationships. - Included interactive HTML visualization for generated graphs. - Updated .gitignore to include new directories and files. - Added example environment configuration file (.env.example) for API key setup. - Created README.md with installation and usage instructions. - Introduced various utility scripts and styles for enhanced functionality.
126 lines
3.2 KiB
Python
126 lines
3.2 KiB
Python
"""
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文本提取模块
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支持从 .md, .txt, .pdf 文件中提取纯文本
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"""
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import os
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from pathlib import Path
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from typing import Optional
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def extract_from_txt(file_path: str) -> str:
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"""从TXT文件提取文本"""
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with open(file_path, 'r', encoding='utf-8') as f:
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return f.read()
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def extract_from_md(file_path: str) -> str:
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"""从Markdown文件提取文本(保留原始格式,不转换HTML)"""
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with open(file_path, 'r', encoding='utf-8') as f:
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return f.read()
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def extract_from_pdf(file_path: str) -> str:
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"""从PDF文件提取文本"""
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try:
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import fitz # PyMuPDF
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except ImportError:
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raise ImportError("请安装 PyMuPDF: pip install PyMuPDF")
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text_parts = []
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with fitz.open(file_path) as doc:
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for page_num, page in enumerate(doc):
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text = page.get_text()
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if text.strip():
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text_parts.append(f"--- 第 {page_num + 1} 页 ---\n{text}")
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return "\n\n".join(text_parts)
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def extract_text(file_path: str) -> str:
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"""
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根据文件扩展名自动选择提取方法
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Args:
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file_path: 文件路径
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Returns:
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提取的纯文本内容
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Raises:
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ValueError: 不支持的文件格式
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FileNotFoundError: 文件不存在
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"""
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path = Path(file_path)
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if not path.exists():
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raise FileNotFoundError(f"文件不存在: {file_path}")
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suffix = path.suffix.lower()
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extractors = {
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'.txt': extract_from_txt,
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'.md': extract_from_md,
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'.markdown': extract_from_md,
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'.pdf': extract_from_pdf,
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}
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extractor = extractors.get(suffix)
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if extractor is None:
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supported = ', '.join(extractors.keys())
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raise ValueError(f"不支持的文件格式: {suffix}。支持的格式: {supported}")
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return extractor(file_path)
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def split_text_into_chunks(text: str, max_chunk_size: int = 8000, overlap: int = 200) -> list[str]:
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"""
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将长文本分割成多个小块,适合Zep处理
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Args:
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text: 原始文本
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max_chunk_size: 每个块的最大字符数
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overlap: 块之间的重叠字符数
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Returns:
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文本块列表
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"""
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if len(text) <= max_chunk_size:
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return [text]
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chunks = []
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start = 0
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while start < len(text):
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end = start + max_chunk_size
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# 尝试在句子边界处分割
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if end < len(text):
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# 查找最近的句子结束符
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for sep in ['。', '!', '?', '\n\n', '. ', '! ', '? ']:
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last_sep = text[start:end].rfind(sep)
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if last_sep != -1 and last_sep > max_chunk_size * 0.5:
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end = start + last_sep + len(sep)
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break
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chunk = text[start:end].strip()
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if chunk:
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chunks.append(chunk)
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# 下一个块从重叠位置开始
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start = end - overlap if end < len(text) else len(text)
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return chunks
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if __name__ == "__main__":
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# 测试
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import sys
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if len(sys.argv) > 1:
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file_path = sys.argv[1]
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text = extract_text(file_path)
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print(f"提取了 {len(text)} 个字符")
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print(f"前500字符:\n{text[:500]}")
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