yxxandClaude Code
4fc26a11e1
- pdf.py `_block_list_item` 改为按 AST 顺序逐段输出：正文暂存为行内标记文本， 遇嵌套列表先 flush 再递归，之后继续后续正文，保持「父段—子列表—后续段」原始顺序 - pdf.py/docx.py 列表项直接行内节点改走 `_render_inline_node`，保留加粗/链接语义， 不再只渲染 children 而丢掉格式（PDF 链接以 /URI 注解保留，DOCX 写入 w:hyperlink） - docx.py `_render_inline_node` 增加 bold/italic 默认值，便于列表项直接调用 - 契约文档 StaticRenderer 状态「计划新增」→「已实现」 - 新增回归测试：混合嵌套顺序、PDF/DOCX 列表项行内语义 Co-Authored-By: Claude Code <noreply@anthropic.com>
340 lines
13 KiB
Python
340 lines
13 KiB
Python
"""PdfExporter：Document AST → PDF（reportlab platypus）。
|
||
|
||
v1 为文本优先：标题/段落/行内强调与链接/列表/引用/表格/代码块/数学文本均可导出；
|
||
function_plot 与 mermaid 保留源码占位并记 warning。中文字体用 reportlab 内置
|
||
STSong-Light CID 字体，避免外部字体依赖。CID 字体无独立 bold/italic 字重，
|
||
故行内强调退化为普通文本（内容不丢、样式简化），标题靠字号区分层级。
|
||
"""
|
||
|
||
from __future__ import annotations
|
||
|
||
import html as _html
|
||
from io import BytesIO
|
||
|
||
from reportlab.lib.enums import TA_CENTER
|
||
from reportlab.lib.pagesizes import A4, letter
|
||
from reportlab.lib.styles import ParagraphStyle
|
||
from reportlab.lib.units import mm
|
||
from reportlab.pdfbase import pdfmetrics
|
||
from reportlab.pdfbase.cidfonts import UnicodeCIDFont
|
||
from reportlab.platypus import (
|
||
Paragraph,
|
||
Preformatted,
|
||
SimpleDocTemplate,
|
||
Spacer,
|
||
Table,
|
||
TableStyle,
|
||
)
|
||
from reportlab.platypus.flowables import HRFlowable
|
||
|
||
from app.contracts import ExportOptions
|
||
from app.export.document import Document, DocumentNode, ExportResult
|
||
from app.export.exporters._common import (
|
||
MERMAID_WARNING,
|
||
PLOT_PLACEHOLDER_WARNING,
|
||
RAW_HTML_WARNING,
|
||
format_meta_value,
|
||
safe_url,
|
||
)
|
||
|
||
_FONT = "STSong-Light"
|
||
pdfmetrics.registerFont(UnicodeCIDFont(_FONT))
|
||
|
||
_MIME = "application/pdf"
|
||
|
||
_PAGE_SIZES = {"a4": A4, "letter": letter}
|
||
|
||
# 标题字号随层级递减；标题不依赖粗体（CID 无粗体字重），靠字号拉开层级
|
||
_HEADING_SIZES = {1: 20, 2: 16, 3: 14, 4: 12, 5: 11, 6: 10.5}
|
||
# 引用块文字颜色，与 HtmlExporter 的引用灰一致
|
||
_QUOTE_COLOR = "#57606a"
|
||
|
||
|
||
def _make_styles() -> dict[str, ParagraphStyle]:
|
||
body = ParagraphStyle(
|
||
"pdf-body",
|
||
fontName=_FONT,
|
||
fontSize=10.5,
|
||
leading=16,
|
||
spaceAfter=6,
|
||
)
|
||
title = ParagraphStyle("pdf-title", parent=body, fontSize=22, leading=28, spaceAfter=12)
|
||
quote = ParagraphStyle(
|
||
"pdf-quote",
|
||
parent=body,
|
||
leftIndent=14,
|
||
textColor="#57606a",
|
||
spaceBefore=4,
|
||
spaceAfter=6,
|
||
)
|
||
code = ParagraphStyle(
|
||
"pdf-code",
|
||
parent=body,
|
||
fontSize=9,
|
||
leading=12,
|
||
leftIndent=6,
|
||
rightIndent=6,
|
||
backColor="#f6f8fa",
|
||
borderColor="#d0d7de",
|
||
borderWidth=0.5,
|
||
borderPadding=6,
|
||
spaceBefore=4,
|
||
spaceAfter=8,
|
||
)
|
||
math = ParagraphStyle("pdf-math", parent=body, alignment=TA_CENTER, spaceBefore=6)
|
||
cell = ParagraphStyle("pdf-cell", parent=body, fontSize=10, leading=14, spaceAfter=0)
|
||
cell_head = ParagraphStyle(
|
||
"pdf-cell-head", parent=cell, textColor="#1f2328", fontSize=10
|
||
)
|
||
meta = ParagraphStyle("pdf-meta", parent=body, fontSize=8.5, leading=13, textColor="#57606a")
|
||
styles: dict[str, ParagraphStyle] = {
|
||
"body": body,
|
||
"title": title,
|
||
"quote": quote,
|
||
"code": code,
|
||
"math": math,
|
||
"cell": cell,
|
||
"cell_head": cell_head,
|
||
"meta": meta,
|
||
}
|
||
for level, size in _HEADING_SIZES.items():
|
||
styles[f"h{level}"] = ParagraphStyle(
|
||
f"pdf-h{level}",
|
||
parent=body,
|
||
fontSize=size,
|
||
leading=size * 1.4,
|
||
spaceBefore=14 if level <= 2 else 10,
|
||
spaceAfter=6,
|
||
)
|
||
return styles
|
||
|
||
|
||
class PdfExporter:
|
||
"""实现 DocumentExporter：递归渲染 Document AST 为 PDF 字节流。"""
|
||
|
||
def render(self, document: Document, options: ExportOptions) -> ExportResult:
|
||
"""同步渲染；CPU 密集，调用方应放入线程执行，避免阻塞事件循环。"""
|
||
self._styles = _make_styles()
|
||
warnings: list[str] = []
|
||
|
||
page = _PAGE_SIZES.get((options.page_size or "A4").lower(), A4)
|
||
buf = BytesIO()
|
||
doc = SimpleDocTemplate(
|
||
buf,
|
||
pagesize=page,
|
||
leftMargin=20 * mm,
|
||
rightMargin=20 * mm,
|
||
topMargin=18 * mm,
|
||
bottomMargin=18 * mm,
|
||
title=str(document.attributes.get("title") or "") or None,
|
||
)
|
||
|
||
story: list = []
|
||
self._render_header(document, options, story)
|
||
self._render_children(document.children, story, warnings)
|
||
|
||
doc.build(story)
|
||
return ExportResult(content=buf.getvalue(), mime_type=_MIME, warnings=warnings)
|
||
|
||
async def export(self, document: Document, options: ExportOptions) -> ExportResult:
|
||
"""契约要求的 async 接口；渲染本身同步，直接转发到 render。"""
|
||
return self.render(document, options)
|
||
|
||
# --- 文档头部 ---
|
||
def _render_header(self, document: Document, options: ExportOptions, story: list) -> None:
|
||
title = str(document.attributes.get("title") or "")
|
||
if options.include_title and title:
|
||
story.append(Paragraph(_html.escape(title), self._styles["title"]))
|
||
if options.include_metadata:
|
||
metadata = document.attributes.get("metadata")
|
||
if metadata:
|
||
for key, value in metadata.items():
|
||
text = f"{_html.escape(str(key))}: {_html.escape(format_meta_value(value))}"
|
||
story.append(Paragraph(text, self._styles["meta"]))
|
||
|
||
# --- 块级 ---
|
||
def _render_children(self, children: list[DocumentNode], story: list, warnings: list[str]) -> None:
|
||
for child in children:
|
||
self._render_block(child, story, warnings)
|
||
|
||
def _render_block(self, node: DocumentNode, story: list, warnings: list[str]) -> None:
|
||
handler = getattr(self, f"_block_{node.type}", None)
|
||
if handler is not None:
|
||
handler(node, story, warnings)
|
||
else:
|
||
warnings.append(f"无法表示的节点类型已跳过：{node.type}")
|
||
|
||
def _block_heading(self, node: DocumentNode, story: list, warnings: list[str]) -> None:
|
||
level = max(1, min(6, int(node.attributes.get("level", 1))))
|
||
inline = self._render_inline(node.children, warnings)
|
||
story.append(Paragraph(inline, self._styles[f"h{level}"]))
|
||
|
||
def _block_paragraph(self, node: DocumentNode, story: list, warnings: list[str]) -> None:
|
||
story.append(Paragraph(self._render_inline(node.children, warnings), self._styles["body"]))
|
||
|
||
def _block_blockquote(self, node: DocumentNode, story: list, warnings: list[str]) -> None:
|
||
# 引用块的直接子节点是块级节点（paragraph/list 等），不能交给行内渲染器，
|
||
# 否则正文会被当作「无法表示的行内节点」丢弃；逐个渲染并继承引用缩进/颜色。
|
||
for child in node.children:
|
||
if child.type == "paragraph":
|
||
story.append(
|
||
Paragraph(self._render_inline(child.children, warnings), self._styles["quote"])
|
||
)
|
||
elif child.type == "list":
|
||
self._block_list(child, story, warnings, indent=14, color=_QUOTE_COLOR)
|
||
else:
|
||
self._render_block(child, story, warnings)
|
||
|
||
def _block_list(
|
||
self,
|
||
node: DocumentNode,
|
||
story: list,
|
||
warnings: list[str],
|
||
indent: int = 14,
|
||
color: str | None = None,
|
||
) -> None:
|
||
ordered = bool(node.attributes.get("ordered"))
|
||
for index, item in enumerate(node.children, start=1):
|
||
self._block_list_item(item, story, warnings, ordered, index, indent, color)
|
||
|
||
def _block_list_item(
|
||
self,
|
||
item: DocumentNode,
|
||
story: list,
|
||
warnings: list[str],
|
||
ordered: bool,
|
||
index: int,
|
||
indent: int,
|
||
color: str | None = None,
|
||
) -> None:
|
||
if item.attributes.get("task"):
|
||
marker = "☑ " if item.attributes.get("checked") else "☐ "
|
||
else:
|
||
marker = f"{index}. " if ordered else "• "
|
||
style_kwargs: dict = dict(
|
||
parent=self._styles["body"],
|
||
leftIndent=indent,
|
||
firstLineIndent=-7,
|
||
spaceAfter=2,
|
||
)
|
||
if color:
|
||
style_kwargs["textColor"] = color
|
||
style = ParagraphStyle(f"pdf-li-{indent}-{color or 'normal'}", **style_kwargs)
|
||
# 按 AST 顺序逐段输出：正文暂存为行内标记文本，遇到嵌套列表先 flush 再递归、
|
||
# 之后继续后续正文，保持「父段—子列表—后续段」的原始顺序（而不是把所有正文
|
||
# 都挤到子列表之前）。直接行内节点（text/strong/link 等）走 _render_inline_node，
|
||
# 保留加粗/链接等语义，不能只渲染其 children 而丢掉格式。
|
||
parts: list[str] = []
|
||
first = True
|
||
|
||
def flush() -> None:
|
||
nonlocal first
|
||
text = "<br/>".join(parts)
|
||
if first:
|
||
text = marker + text
|
||
first = False
|
||
if text:
|
||
story.append(Paragraph(text, style))
|
||
parts.clear()
|
||
|
||
for child in item.children:
|
||
if child.type == "list":
|
||
flush()
|
||
self._block_list(child, story, warnings, indent + 14, color)
|
||
elif child.type == "paragraph":
|
||
parts.append(self._render_inline(child.children, warnings))
|
||
else:
|
||
parts.append(self._render_inline_node(child, warnings))
|
||
flush()
|
||
|
||
def _block_table(self, node: DocumentNode, story: list, warnings: list[str]) -> None:
|
||
rows = node.children
|
||
if not rows:
|
||
return
|
||
data: list[list[Paragraph]] = []
|
||
head_row_count = 0
|
||
for row in rows:
|
||
head = bool(row.attributes.get("head"))
|
||
if head:
|
||
head_row_count += 1
|
||
cells = [
|
||
Paragraph(
|
||
self._render_inline(cell.children, warnings),
|
||
self._styles["cell_head" if cell.attributes.get("head") else "cell"],
|
||
)
|
||
for cell in row.children
|
||
]
|
||
data.append(cells)
|
||
table = Table(data, repeatRows=head_row_count)
|
||
commands = [
|
||
("GRID", (0, 0), (-1, -1), 0.5, "#d0d7de"),
|
||
("VALIGN", (0, 0), (-1, -1), "TOP"),
|
||
("LEFTPADDING", (0, 0), (-1, -1), 6),
|
||
("RIGHTPADDING", (0, 0), (-1, -1), 6),
|
||
("TOPPADDING", (0, 0), (-1, -1), 4),
|
||
("BOTTOMPADDING", (0, 0), (-1, -1), 4),
|
||
]
|
||
if head_row_count:
|
||
commands.append(("BACKGROUND", (0, 0), (-1, head_row_count - 1), "#f6f8fa"))
|
||
table.setStyle(TableStyle(commands))
|
||
story.append(table)
|
||
|
||
def _block_code_block(self, node: DocumentNode, story: list, warnings: list[str]) -> None:
|
||
story.append(Preformatted(node.text, self._styles["code"]))
|
||
|
||
def _block_thematic_break(self, node: DocumentNode, story: list, warnings: list[str]) -> None:
|
||
story.append(Spacer(1, 4))
|
||
story.append(HRFlowable(width="100%", color="#d0d7de", thickness=0.5))
|
||
story.append(Spacer(1, 6))
|
||
|
||
def _block_mermaid(self, node: DocumentNode, story: list, warnings: list[str]) -> None:
|
||
warnings.append(MERMAID_WARNING)
|
||
story.append(Preformatted(node.text, self._styles["code"]))
|
||
|
||
def _block_function_plot(self, node: DocumentNode, story: list, warnings: list[str]) -> None:
|
||
warnings.append(PLOT_PLACEHOLDER_WARNING)
|
||
story.append(Preformatted(node.text, self._styles["code"]))
|
||
|
||
def _block_math_block(self, node: DocumentNode, story: list, warnings: list[str]) -> None:
|
||
story.append(Paragraph(f"$${_html.escape(node.text)}$$", self._styles["math"]))
|
||
|
||
def _block_html_block(self, node: DocumentNode, story: list, warnings: list[str]) -> None:
|
||
# 原始 HTML 不可信，按纯文本保留正文
|
||
warnings.append(RAW_HTML_WARNING)
|
||
story.append(Paragraph(_html.escape(node.text), self._styles["body"]))
|
||
|
||
# --- 行内（产出 reportlab Paragraph 标记文本） ---
|
||
def _render_inline(self, children: list[DocumentNode], warnings: list[str]) -> str:
|
||
return "".join(self._render_inline_node(child, warnings) for child in children)
|
||
|
||
def _render_inline_node(self, node: DocumentNode, warnings: list[str]) -> str:
|
||
t = node.type
|
||
if t == "text":
|
||
return _html.escape(node.text)
|
||
if t in ("strong", "emphasis"):
|
||
return self._render_inline(node.children, warnings)
|
||
if t == "codespan":
|
||
return f'<font size="9">{_html.escape(node.text)}</font>'
|
||
if t == "link":
|
||
inner = self._render_inline(node.children, warnings)
|
||
href = str(node.attributes.get("href") or "")
|
||
safe_href = safe_url(href)
|
||
if safe_href is None:
|
||
warnings.append(f"链接协议不安全，已降级为纯文本：{href!r}")
|
||
return inner
|
||
return f'<a href="{_html.escape(safe_href)}">{inner}</a>'
|
||
if t == "image":
|
||
src = str(node.attributes.get("src") or "")
|
||
alt = str(node.attributes.get("alt") or "")
|
||
if safe_url(src) is None:
|
||
warnings.append(f"图片地址不安全，已跳过：{src!r}")
|
||
else:
|
||
warnings.append("图片未内嵌到 PDF，已用替代文本表示")
|
||
return _html.escape(alt) if alt else ""
|
||
if t == "math_inline":
|
||
return f"\\({_html.escape(node.text)}\\)"
|
||
if t == "linebreak":
|
||
return "<br/>"
|
||
warnings.append(f"无法表示的行内节点已跳过：{t}")
|
||
return ""
|