PageIndex/pageindex/parser/markdown.py
mountain b2756c73d2 refactor(sdk): typed returns, protocol contract, parser layering
Engineering-quality cleanups from the SDK review (no behavior change):

- Return-type discoverability: add pageindex/types.py with TypedDicts
  (DocumentInfo, DocumentDetail, PageContent) and annotate Collection /
  Backend methods with them; add docstrings to every public Collection
  method (including the get_page_content `pages` spec). Exported from the
  package. Zero runtime cost — these are plain dicts.

- Backend protocol as a real contract:
  * query_stream is an async generator, so the protocol now declares it
    as `def ... -> AsyncIterator[QueryEvent]` (not `async def`, which
    typed it as a coroutine and never matched the implementations).
  * custom-parser support is expressed as a runtime_checkable
    SupportsParserRegistration capability protocol; the client uses
    isinstance(...) instead of hasattr(...) duck-typing.

- Parser layering: move count_tokens into a leaf module pageindex/tokens.py
  so parser/* imports it from there instead of reaching back into
  pageindex.index (a reverse dependency). index.utils re-exports it for
  backward compatibility.

Adds tests/test_architecture.py enforcing: parser never imports index,
count_tokens is a single shared leaf, the capability protocol works,
both backends satisfy Backend, and the TypedDicts are exported.

Claude-Session: https://claude.ai/code/session_01Kx5DgKbhK1N8autqXH8SmS
2026-07-07 12:15:34 +08:00

88 lines
3.2 KiB
Python

import re
from pathlib import Path
from .protocol import ContentNode, ParsedDocument
from ..tokens import count_tokens
class MarkdownParser:
def supported_extensions(self) -> list[str]:
return [".md", ".markdown"]
def parse(self, file_path: str, **kwargs) -> ParsedDocument:
path = Path(file_path)
model = kwargs.get("model")
with open(path, "r", encoding="utf-8") as f:
content = f.read()
lines = content.split("\n")
headers = self._extract_headers(lines)
nodes = self._build_nodes(headers, lines, model, doc_title=path.stem)
return ParsedDocument(doc_name=path.stem, nodes=nodes)
def _extract_headers(self, lines: list[str]) -> list[dict]:
header_pattern = r"^(#{1,6})\s+(.+)$"
code_block_pattern = r"^```"
headers = []
in_code_block = False
for line_num, line in enumerate(lines, 1):
stripped = line.strip()
if re.match(code_block_pattern, stripped):
in_code_block = not in_code_block
continue
if not in_code_block and stripped:
match = re.match(header_pattern, stripped)
if match:
headers.append({
"title": match.group(2).strip(),
"level": len(match.group(1)),
"line_num": line_num,
})
return headers
def _build_nodes(self, headers: list[dict], lines: list[str], model: str | None,
doc_title: str = "Document") -> list[ContentNode]:
nodes = []
# A file with no headings at all still has content — index it as a
# single node instead of producing zero nodes (which would push an
# empty page list into the LLM pipeline).
if not headers:
text = "\n".join(lines).strip()
if text:
nodes.append(ContentNode(
content=text,
tokens=count_tokens(text, model=model),
title=doc_title,
index=1,
level=1,
))
return nodes
# Content before the first heading (abstract, preamble) would
# otherwise be silently dropped and become unretrievable.
preamble = "\n".join(lines[: headers[0]["line_num"] - 1]).strip()
if preamble:
nodes.append(ContentNode(
content=preamble,
tokens=count_tokens(preamble, model=model),
title=doc_title,
index=1,
level=headers[0]["level"],
))
for i, header in enumerate(headers):
start = header["line_num"] - 1
end = headers[i + 1]["line_num"] - 1 if i + 1 < len(headers) else len(lines)
text = "\n".join(lines[start:end]).strip()
tokens = count_tokens(text, model=model)
nodes.append(ContentNode(
content=text,
tokens=tokens,
title=header["title"],
index=header["line_num"],
level=header["level"],
))
return nodes