Initial commit: AI 知识库文档智能分块工具

parsers/xlsx_parser.py

@@ -0,0 +1,125 @@
+"""XLSX 解析器，使用 openpyxl 提取 Excel 数据并转换为 Markdown 表格格式"""
+
+import os
+from typing import List
+
+from openpyxl import load_workbook
+
+from exceptions import ParseError
+from parsers.base import BaseParser
+
+
+class XlsxParser(BaseParser):
+    """XLSX 解析器，遍历所有工作表，处理合并单元格，以 sheet 名为标题，数据转 Markdown 表格"""
+
+    def supported_extensions(self) -> List[str]:
+        return [".xlsx"]
+
+    def parse(self, file_path: str) -> str:
+        file_name = os.path.basename(file_path)
+
+        try:
+            workbook = load_workbook(file_path)
+        except Exception as e:
+            raise ParseError(file_name, f"XLSX 文件打开失败: {e}")
+
+        try:
+            return self._workbook_to_md(workbook)
+        except ParseError:
+            raise
+        except Exception as e:
+            raise ParseError(file_name, f"XLSX 文件解析失败: {e}")
+
+    def _workbook_to_md(self, workbook) -> str:
+        """将整个工作簿转换为 Markdown"""
+        sheet_parts = []
+
+        for sheetname in workbook.sheetnames:
+            sheet = workbook[sheetname]
+            md = self._sheet_to_md(sheet, sheetname)
+            if md:
+                sheet_parts.append(md)
+
+        return "\n\n".join(sheet_parts)
+
+    def _sheet_to_md(self, sheet, sheetname: str) -> str:
+        """将单个工作表转换为 Markdown 表格"""
+        # 处理合并单元格：填充合并区域的值
+        merged_values = self._get_merged_cell_values(sheet)
+
+        # 收集所有行数据
+        rows = list(sheet.iter_rows())
+        if not rows:
+            return ""
+
+        # 第一行作为表头
+        headers = []
+        for cell in rows[0]:
+            value = self._resolve_cell_value(cell, merged_values)
+            headers.append(self._escape_cell(value))
+
+        if not any(h.strip() for h in headers):
+            return ""
+
+        lines = [f"## {sheetname}", ""]
+
+        # 表头行
+        lines.append("| " + " | ".join(headers) + " |")
+        # 分隔行
+        lines.append("| " + " | ".join("---" for _ in headers) + " |")
+
+        # 数据行
+        for row in rows[1:]:
+            cells = []
+            for cell in row:
+                value = self._resolve_cell_value(cell, merged_values)
+                cells.append(self._escape_cell(value))
+            lines.append("| " + " | ".join(cells) + " |")
+
+        return "\n".join(lines)
+
+    @staticmethod
+    def _get_merged_cell_values(sheet) -> dict:
+        """
+        获取合并单元格的值映射。
+
+        返回 dict: {cell_coordinate: value} 对于合并区域内的所有单元格，
+        值来自合并区域左上角的单元格。
+        """
+        merged_values = {}
+        for merged_range in sheet.merged_cells.ranges:
+            # 左上角单元格的值
+            top_left_value = sheet.cell(
+                row=merged_range.min_row,
+                column=merged_range.min_col
+            ).value
+
+            # 填充合并区域内所有单元格
+            for row in range(merged_range.min_row, merged_range.max_row + 1):
+                for col in range(merged_range.min_col, merged_range.max_col + 1):
+                    coord = sheet.cell(row=row, column=col).coordinate
+                    merged_values[coord] = top_left_value
+
+        return merged_values
+
+    @staticmethod
+    def _resolve_cell_value(cell, merged_values: dict):
+        """获取单元格的值，优先使用合并单元格映射"""
+        value = cell.value
+        if value is None:
+            value = merged_values.get(cell.coordinate)
+        return value
+
+    @staticmethod
+    def _escape_cell(value) -> str:
+        """转义单元格内容，避免破坏 Markdown 表格结构"""
+        if value is None:
+            return ""
+
+        cell_str = str(value)
+        cell_str = cell_str.replace("\r\n", "<br>")
+        cell_str = cell_str.replace("\n", "<br>")
+        cell_str = cell_str.replace("|", "&#124;")
+        cell_str = cell_str.replace("`", "&#96;")
+
+        return cell_str