Files
2026-07-13 12:08:54 +08:00

354 lines
14 KiB
Python

"""Docling raw bundle downloader.
Talks to Docling Serve v1 over HTTP:
- ``POST /v1/convert/file/async`` — multipart upload, returns ``task_id``,
- ``GET /v1/status/poll/{task_id}?wait=5`` — long-poll for terminal state,
- ``GET /v1/result/{task_id}`` — zip download (only on ``success``).
The zip is extracted safely under ``raw_dir/`` (refusing path traversal /
absolute entries). A success manifest is written atomically at the very
end; mid-run crashes therefore leave the directory in a state the cache
layer marks as invalid (no manifest → miss → re-download).
Pipeline constants (``pipeline``, ``target_type``, ``to_formats``,
``image_export_mode``) are intentionally **not** env-driven — the sidecar
flow depends on them — and are recorded inside the manifest so a future
code change automatically invalidates pre-existing caches.
"""
from __future__ import annotations
import asyncio
import json
import os
import time
from collections.abc import Mapping
from pathlib import Path
from typing import TYPE_CHECKING, Any
from urllib.parse import quote
from lightrag.parser.external._common import (
env_bool,
env_int,
raise_for_status_with_detail,
)
from lightrag.parser.external._zip import safe_extract_zip
from lightrag.parser.external.docling.cache import (
compute_options_signature,
current_endpoint_signature,
snapshot_tunable_env,
)
from lightrag.parser.external.docling.manifest import (
build_and_write_docling_manifest,
select_main_json,
)
from lightrag.utils import logger
if TYPE_CHECKING:
import httpx
else:
try:
import httpx
except ImportError: # pragma: no cover
httpx = None
# ---------------------------------------------------------------------------
# Fixed pipeline constants (NOT env-driven)
# ---------------------------------------------------------------------------
PIPELINE = "standard"
TARGET_TYPE = "zip"
TO_FORMATS: tuple[str, ...] = ("json", "md")
IMAGE_EXPORT_MODE = "referenced"
FIXED_CONSTANTS: dict[str, object] = {
"pipeline": PIPELINE,
"target_type": TARGET_TYPE,
"to_formats": list(TO_FORMATS),
"image_export_mode": IMAGE_EXPORT_MODE,
}
CONVERT_PATH = "/v1/convert/file/async"
POLL_PATH = "/v1/status/poll/{task_id}"
RESULT_PATH = "/v1/result/{task_id}"
DEFAULT_POLL_WAIT_SECONDS = 5
DEFAULT_MAX_POLLS = 240 # 240 * 5s long-poll ≈ 20 min worst case
# ConversionStatus enum from the docling-serve OpenAPI
SUCCESS_STATES = {"success"}
FAILURE_STATES = {"failure", "partial_success", "skipped"}
IN_PROGRESS_STATES = {"pending", "started"}
class DoclingRawClient:
"""Downloads docling-serve bundles into ``raw_dir``.
Construct once per parse call (cheap). Reads ``DOCLING_*`` envs at
``__init__`` time, so callers can flip env between calls and pick up
the new values without holding a stale instance.
"""
def __init__(self, *, overrides: "Mapping[str, Any] | None" = None) -> None:
self._overrides = overrides or {}
self.endpoint = current_endpoint_signature()
if not self.endpoint:
raise ValueError("DOCLING_ENDPOINT is required")
self.engine_version = os.getenv("DOCLING_ENGINE_VERSION", "").strip()
self.do_ocr = env_bool("DOCLING_DO_OCR", True)
self.force_ocr = (
bool(self._overrides["force_ocr"])
if "force_ocr" in self._overrides
else env_bool("DOCLING_FORCE_OCR", True)
)
self.ocr_engine = os.getenv("DOCLING_OCR_ENGINE", "auto").strip() or "auto"
self.ocr_preset = os.getenv("DOCLING_OCR_PRESET", "auto").strip() or "auto"
self.ocr_lang_raw = os.getenv("DOCLING_OCR_LANG", "").strip()
self.do_formula_enrichment = env_bool("DOCLING_DO_FORMULA_ENRICHMENT", False)
# Poll cadence: docling-serve's ``?wait=N`` is a server-side long-poll
# window. ``DOCLING_POLL_INTERVAL_SECONDS`` sets that window; the
# client does NOT add its own sleep between polls. ``DOCLING_MAX_POLLS``
# bounds the total polling budget — exceeding it raises ``TimeoutError``.
wait = env_int("DOCLING_POLL_INTERVAL_SECONDS", DEFAULT_POLL_WAIT_SECONDS)
self.poll_wait_seconds = wait if wait > 0 else DEFAULT_POLL_WAIT_SECONDS
max_polls = env_int("DOCLING_MAX_POLLS", DEFAULT_MAX_POLLS)
self.max_poll_attempts = max_polls if max_polls > 0 else DEFAULT_MAX_POLLS
# ------------------------------------------------------------------
# Public API
# ------------------------------------------------------------------
async def download_into(
self,
raw_dir: Path,
source_file_path: Path,
*,
upload_filename: str | None = None,
):
"""Upload, poll, download, extract, and write the manifest.
``upload_filename`` overrides the multipart filename sent to
docling-serve (defaults to ``source_file_path.name``). The pipeline
passes the canonical, hint-stripped document name here so the
bundle's ``<stem>.json`` ends up canonical too — otherwise a file
named ``report.[docling].pdf`` would produce ``report.[docling].json``
inside the bundle, and the adapter (which only knows the canonical
``report.pdf``) would not be able to locate it via the preferred
``<stem>.json`` lookup.
Pre-condition: caller cleared ``raw_dir`` (e.g. via
:func:`lightrag.parser.external.clear_dir_contents`). This method
does not clean the directory itself — keeping that explicit at the
``parse_docling`` entry point.
"""
if httpx is None:
raise RuntimeError(
"httpx is required for Docling parsing but is not installed"
)
raw_dir.mkdir(parents=True, exist_ok=True)
effective_filename = upload_filename or source_file_path.name
timeout = httpx.Timeout(120.0, connect=30.0)
async with httpx.AsyncClient(timeout=timeout) as client:
task_id = await self._submit(
client, source_file_path, filename=effective_filename
)
await self._poll_until_done(client, task_id)
payload = await self._download_zip_bytes(client, task_id)
safe_extract_zip(payload, raw_dir)
# Defensive: confirm the main JSON exists before anyone reads the
# bundle. Look it up by the *uploaded* filename's stem — that's
# what docling-serve uses to name the JSON inside the zip.
select_main_json(raw_dir, Path(effective_filename))
options_signature = compute_options_signature(
tunable_env=snapshot_tunable_env(self._overrides),
fixed_constants=FIXED_CONSTANTS,
)
return build_and_write_docling_manifest(
raw_dir,
source_file_path=source_file_path,
task_id=task_id,
endpoint_signature=self.endpoint,
engine_version=self.engine_version,
options_signature=options_signature,
fixed_constants=FIXED_CONSTANTS,
recorded_filename=effective_filename,
)
# ------------------------------------------------------------------
# Upload + poll + download
# ------------------------------------------------------------------
def _build_multipart_data(self) -> dict[str, str | list[str]]:
"""Form fields (everything except the file payload).
Returns a ``dict`` (not a list of tuples): httpx ≥ 0.28 short-circuits
non-``Mapping`` ``data`` into raw-content encoding and ignores
``files=`` entirely, producing a sync-only stream that an
``AsyncClient`` then rejects. List-valued entries are emitted as
repeated form keys by ``MultipartStream``, matching docling-serve's
pydantic ``List[Enum]`` form parsing. ``ocr_lang`` is omitted entirely
when empty so the engine uses its own default.
"""
data: dict[str, str | list[str]] = {
"pipeline": PIPELINE,
"target_type": TARGET_TYPE,
"image_export_mode": IMAGE_EXPORT_MODE,
"do_ocr": _bool_form(self.do_ocr),
"force_ocr": _bool_form(self.force_ocr),
"ocr_engine": self.ocr_engine,
"ocr_preset": self.ocr_preset,
"do_formula_enrichment": _bool_form(self.do_formula_enrichment),
"to_formats": list(TO_FORMATS),
}
if self.ocr_lang_raw:
langs = _parse_ocr_lang(self.ocr_lang_raw)
if langs:
data["ocr_lang"] = langs
return data
async def _submit(
self,
client: "httpx.AsyncClient",
source_file_path: Path,
*,
filename: str,
) -> str:
url = f"{self.endpoint}{CONVERT_PATH}"
# Hand httpx a file object so its MultipartStream reads the body in
# chunks instead of materializing the whole PDF/PPTX in worker memory.
# With ``max_parallel_parse_docling > 1`` a per-doc bytes copy can
# OOM the worker before docling-serve ever sees the request.
with source_file_path.open("rb") as fh:
files = {"files": (filename, fh, "application/octet-stream")}
resp = await client.post(
url, data=self._build_multipart_data(), files=files
)
raise_for_status_with_detail(resp, f"Docling upload for {filename!r}")
payload = resp.json() if resp.text else {}
task_id = str(payload.get("task_id") or payload.get("id") or "").strip()
if not task_id:
raise RuntimeError(f"Docling upload response missing task_id: {payload!r}")
return task_id
async def _poll_until_done(
self,
client: "httpx.AsyncClient",
task_id: str,
) -> None:
encoded_task_id = quote(task_id, safe="")
url = f"{self.endpoint}{POLL_PATH.format(task_id=encoded_task_id)}"
params = {"wait": self.poll_wait_seconds}
for _ in range(self.max_poll_attempts):
iteration_started = time.monotonic()
resp = await client.get(url, params=params)
raise_for_status_with_detail(resp, f"Docling task {task_id} poll")
payload = resp.json() if resp.text else {}
status = str(
payload.get("task_status") or payload.get("status") or ""
).lower()
if status in SUCCESS_STATES:
return
if status in FAILURE_STATES:
raise RuntimeError(_format_failure(task_id, status, payload))
if status not in IN_PROGRESS_STATES:
# Unknown status: keep polling, but surface it so operators notice.
logger.warning(
"[docling] unknown task status %r for task %s; continuing to poll",
status,
task_id,
)
# The intended cadence is one poll per ``poll_wait_seconds`` — the
# design relies on docling-serve's ``?wait=N`` long-polling for
# that. Some deployments return immediately instead, which would
# burn through ``max_poll_attempts`` in milliseconds and fail
# with a spurious timeout. Cap each iteration at the configured
# interval ourselves so the total budget holds either way.
elapsed = time.monotonic() - iteration_started
remaining = self.poll_wait_seconds - elapsed
if remaining > 0:
await asyncio.sleep(remaining)
raise TimeoutError(f"Docling task {task_id} polling timeout")
async def _download_zip_bytes(
self,
client: "httpx.AsyncClient",
task_id: str,
) -> bytes:
encoded_task_id = quote(task_id, safe="")
url = f"{self.endpoint}{RESULT_PATH.format(task_id=encoded_task_id)}"
resp = await client.get(url)
raise_for_status_with_detail(resp, f"Docling result {task_id} download")
ctype = resp.headers.get("content-type", "")
if "zip" not in ctype.lower():
raise RuntimeError(
f"Docling result {task_id} returned non-zip content-type "
f"{ctype!r}; body prefix={resp.text[:400]!r}"
)
return resp.content
# ---------------------------------------------------------------------------
# Helpers
# ---------------------------------------------------------------------------
def _bool_form(v: bool) -> str:
return "true" if v else "false"
def _parse_ocr_lang(raw: str) -> list[str]:
"""Best-effort parser for ``DOCLING_OCR_LANG``.
Accepts a JSON array (``["en","zh"]``) or a comma-separated list
(``en,zh``). Returns a list of stripped non-empty strings; empty in →
empty out.
"""
try:
parsed = json.loads(raw)
except json.JSONDecodeError:
parsed = None
if isinstance(parsed, list):
return [str(x).strip() for x in parsed if str(x).strip()]
return [item.strip() for item in raw.split(",") if item.strip()]
def _format_failure(task_id: str, status: str, payload: Any) -> str:
if isinstance(payload, dict):
err = (
payload.get("error_message")
or payload.get("error")
or payload.get("message")
or "<no error_message>"
)
else:
err = "<no error_message>"
truncated = json.dumps(payload, ensure_ascii=False)[:400]
return f"Docling task {task_id} ended in {status}: {err}; payload={truncated}"
__all__ = [
"DoclingRawClient",
"CONVERT_PATH",
"DEFAULT_MAX_POLLS",
"DEFAULT_POLL_WAIT_SECONDS",
"FIXED_CONSTANTS",
"IMAGE_EXPORT_MODE",
"PIPELINE",
"POLL_PATH",
"RESULT_PATH",
"SUCCESS_STATES",
"FAILURE_STATES",
"TARGET_TYPE",
"TO_FORMATS",
]