Files
siftlode/backend/app/downloads/pipeline.py
T
peter 0cc450d1c9 fix(downloads,sync): bound what one user can make the server fetch, download and spend
SEC-12: the download box accepts an arbitrary http(s) URL and yt-dlp fetches
it from the WORKER, so any approved user could aim the server at the compose
network, the LAN or a cloud metadata endpoint — and read the result off
job.error, where "connection refused" vs "HTTP Error 401" vs "timed out" is a
port scanner. downloads/urlguard.py refuses a URL whose host resolves to a
loopback/private/link-local/reserved address, at enqueue AND again in the
worker (DNS can move in between, and the worker is where the socket opens).
A network-class failure on a `url` job now reports one fixed sentence instead
of the raw transport text; the error CODE is still classified from the
original, so the localized explanation is unchanged. DNS rebinding is
explicitly NOT closed — that needs the connection gated inside yt-dlp — and
the module says so rather than implying more than it does.

SEC-13: `noplaylist` only demotes a video-inside-a-playlist URL to that video,
so a URL that is purely a playlist or channel still expanded into every
entry — one enqueue, unbounded downloads. `playlist_items` pins it to one.
Size was unbounded too: `check_enqueue` compares the CURRENT footprint against
the cap, and a download's size is unknown until it lands, so one job could
overshoot by any amount; the owner's remaining budget is now handed to yt-dlp
as `max_filesize`, applied AFTER the adapter merge so no source adapter can
raise a limit the quota layer set. A join's cut-list is capped at 100: an
accurate join emits two filters per segment into one ffmpeg filter_complex.

SEC-14: the YouTube budget is instance-wide, so one user holding down a
manual sync spent the day for everyone. Per-user (not per-IP — the cost
belongs to the account) 3-per-10-minutes limiters on the two bulk pulls,
subscriptions and playlists, with separate budgets so one does not close the
other. The review also listed /rss, /backfill and /enrich; E3 deleted them,
and search stays unlimited on purpose — it is interactive, not a bulk pull.

Gate: pytest 896 -> 924 (none skipped), vitest 671.
2026-09-05 01:03:24 +02:00

701 lines
32 KiB
Python

"""Child-side download/edit pipeline — the yt-dlp download + ffmpeg edit that runs in the spawned subprocess."""
import logging
import re
import shutil
import time
from datetime import date, datetime, timedelta, timezone
from pathlib import Path
import yt_dlp
from sqlalchemy import select
from app import sysconfig
from app.config import settings
from app.db import SessionLocal
from app.downloads import edit as editmod
from app.downloads import errors as dlerrors
from app.downloads import adapters, credentials, formats, mediakind, probe, quota, service, storage
from app.downloads import urlguard
from app.downloads.jobdb import (
_edit_staging_dir,
_job_status,
_reset_asset_pending,
_set_job,
_staging_dir,
_touch_job,
)
from app.downloads.status import JobStatus
from app.models import DownloadJob, MediaAsset
from app.notifications import create_notification
from app.titles import normalize_title
log = logging.getLogger("siftlode.worker")
class _Aborted(Exception):
"""Raised inside the progress hook when the job was paused/canceled mid-download."""
# Both progress sources call back FAR faster than the database should be touched: yt-dlp fires its
# hook per chunk, and ffmpeg's `-progress pipe:1` emits a block of ~12 lines every ~0.5s while
# run_ffmpeg calls its callbacks once per LINE. Every callback here is a round-trip (`_job_status`
# opens a session and SELECTs; `_set_job` opens one and UPDATE+COMMITs), so unthrottled they cost
# ~10^5 queries on a long job. ONE interval, ONE implementation, used by both paths — three
# hand-rolled copies is how the ffmpeg side ended up unthrottled while the download side was fine.
_DB_WRITE_INTERVAL_S = 1.0
_CANCEL_POLL_INTERVAL_S = 1.0
_THUMB_SUFFIXES = (".jpg", ".jpeg", ".png", ".webp")
# yt-dlp's working files in the staging dir. None of them is ever the finished media, but several
# CAN be the biggest file there (a video-only per-format stream, an abandoned fragment run), so the
# staging fallback must exclude them by name — picking one would store e.g. a silent video-only
# stream as a ready asset.
_YTDLP_TEMP_RE = re.compile(
r"\.part(-Frag\d+)?$" # in-flight download / fragment
r"|\.ytdl$" # resume state
r"|\.temp\.[^.]+$" # merge/postprocess temp
r"|\.f\d+\.[^.]+$", # per-format stream kept before the merge
re.IGNORECASE,
)
def _notify_download_done(db, user_id: int | None, title: str | None, job_id, *, kind: str) -> None:
"""Post a best-effort 'ready' notice to the owner's inbox — downloads/edits used to finish
silently while scheduler jobs and playlist-push already notified (R11 feedback symmetry). A
notification failure must never mask the completed job, so it is isolated + rolled back (mirrors
scheduler._notify_done). `kind` ("download"/"edit") lets the inbox pick accurate copy; the
English title here is only a fallback for an unknown type. `user_id`/`title` are captured by the
caller BEFORE its commit, so reading them here needs no post-commit refresh of an expired row."""
if user_id is None:
return
try:
create_notification(
db,
user_id=user_id,
type="download_done",
title=f"Ready to watch: {title}" if title else "Ready to watch",
data={"title": title, "kind": kind},
)
except Exception:
db.rollback()
log.exception("failed to write download-done notification for job %s", job_id)
def _parse_upload_date(raw) -> date | None:
if not raw:
return None
try:
return datetime.strptime(str(raw), "%Y%m%d").date()
except ValueError:
return None
def _fill_asset_meta_early(asset_id: int, info: dict) -> None:
"""Populate an asset's display metadata from yt-dlp's info_dict the first time it's seen
(only if not already filled at enqueue from our catalog) — so an ad-hoc URL's row shows a
real title + thumbnail while it downloads, not just the URL. Zero extra network cost."""
with SessionLocal() as db:
asset = db.get(MediaAsset, asset_id)
if asset is None or asset.title:
return
# `or info.get("id")` avoids a blank card while downloading when the cleaned title is empty
# (e.g. a title that was only a social engagement prefix); the completion path later sets
# the final title with its own source_ref fallback.
asset.title = normalize_title(info.get("title")) or info.get("id")
asset.uploader = info.get("uploader") or info.get("channel")
asset.uploader_url = adapters.resolve_adapter(None, None, info).uploader_url(info)
asset.thumbnail_url = info.get("thumbnail")
asset.duration_s = int(info["duration"]) if info.get("duration") else None
asset.upload_date = _parse_upload_date(info.get("upload_date"))
asset.source_webpage_url = info.get("webpage_url")
db.commit()
def _make_progress_hook(job_id: int, asset_id: int):
state = {"meta_done": False}
cancelled = _cancel_poll(job_id) # same policy as the ffmpeg path
allow_write = _rate_limiter(_DB_WRITE_INTERVAL_S)
def hook(d: dict) -> None:
# Cooperative pause/cancel: if the job is no longer 'running', abort the download.
if cancelled():
raise _Aborted
if not state["meta_done"] and d.get("info_dict"):
state["meta_done"] = True
try:
_fill_asset_meta_early(asset_id, d["info_dict"])
except Exception: # noqa: BLE001 — metadata is best-effort, never fail a download
pass
if d.get("status") != "downloading":
return
if not allow_write():
return
# yt-dlp downloads the video and audio streams SEPARATELY (each 0→100%), then merges.
# Label the phase so the user understands the bar resetting between streams instead of
# seeing a mysterious 95%→5% jump.
info = d.get("info_dict") or {}
vcodec = info.get("vcodec") or "none"
acodec = info.get("acodec") or "none"
if vcodec != "none" and acodec == "none":
phase = "video"
elif acodec != "none" and vcodec == "none":
phase = "audio"
else:
phase = "media"
total = d.get("total_bytes") or d.get("total_bytes_estimate") or 0
done = d.get("downloaded_bytes") or 0
pct = int(done * 100 / total) if total else 0
_set_job(
job_id,
progress=min(pct, 99),
speed_bps=int(d["speed"]) if d.get("speed") else None,
eta_s=int(d["eta"]) if d.get("eta") else None,
phase=phase,
)
return hook
def _rate_limiter(interval_s: float, *, now=time.monotonic):
"""`should_run()` → True at most once per `interval_s` (the first call always passes).
`now` is injectable so tests drive a clock instead of patching the global one."""
# `None`, not 0.0: "never ran" has to be a VALUE, not a falsy timestamp. A truthiness test here
# reads a legitimate `now() == 0.0` as "never ran" and lets a second call straight through —
# unreachable with real `time.monotonic()`, but `now` exists to be injected, and a test clock
# starting at 0 is the obvious choice. That would let a throttle test encode the wrong
# behaviour and still pass.
state: dict[str, float | None] = {"at": None}
def should_run() -> bool:
t = now()
last = state["at"]
if last is not None and t - last < interval_s:
return False
state["at"] = t
return True
return should_run
def _cancel_poll(job_id: int, interval_s: float = _CANCEL_POLL_INTERVAL_S, *, now=time.monotonic):
"""Cooperative "has this job been paused/cancelled?" poll, rate-limited and sticky: once it
says yes it never queries again. Shared by the yt-dlp hook and run_ffmpeg so cancel latency is
one policy, not one per call site."""
allow = _rate_limiter(interval_s, now=now)
state = {"cancelled": False}
def cancelled() -> bool:
if not state["cancelled"] and allow():
state["cancelled"] = _job_status(job_id) not in ("running", None)
return state["cancelled"]
return cancelled
def _ffmpeg_progress_writer(job_id: int, phase: str, *, now=time.monotonic):
"""`on_progress` for run_ffmpeg: persist a progress row write at most once per interval and only
when the whole-percent value changed (the bar shows integers), plus a separate once-per-interval
heartbeat while the percent is stuck (so a slow re-encode isn't mistaken for a stall)."""
# Progress writes have their OWN 1/interval budget so a heartbeat can never delay a real write (the
# round-1 concern). The heartbeat, in turn, is gated on `last_touch` — the last DB write OR beat —
# so a progress write (which already refreshes updated_at) suppresses a redundant heartbeat that
# same interval, keeping active downloads at ~1 write/interval, not two.
allow_write = _rate_limiter(_DB_WRITE_INTERVAL_S, now=now)
state = {"pct": -1}
last_touch: dict = {"t": None} # monotonic time of the last DB write/heartbeat
def write(pct: float) -> None:
whole = int(pct)
if whole != state["pct"]:
if allow_write():
state["pct"] = whole
_set_job(job_id, progress=whole, phase=phase)
last_touch["t"] = now()
return
# Same integer percent, but ffmpeg IS still working — a slow re-encode (AV1/VP9 -> H.264 or a
# crop on the CPU-only host) can sit on one percent for minutes. Heartbeat updated_at so the
# stall watchdog doesn't kill a live job (B-sub-4) — but only if no write/beat already touched
# the row this interval, so a progressing download doesn't pay a redundant write.
t = now()
if last_touch["t"] is None or t - last_touch["t"] >= _DB_WRITE_INTERVAL_S:
_touch_job(job_id)
last_touch["t"] = t
return write
def _pp_phase(pp: str) -> str:
"""Map a yt-dlp postprocessor class name to a user-facing phase label. ffmpeg post-steps
aren't byte-progress operations (no %), so the UI shows the step name + an indeterminate
pulse — this makes the long merge/finalize legible instead of a silent 'Processing'."""
if "Merg" in pp:
return "merging"
if "ExtractAudio" in pp:
return "audio_extract"
if "Thumbnail" in pp:
return "thumbnail"
if "SponsorBlock" in pp or "ModifyChapters" in pp:
return "sponsorblock"
if "Metadata" in pp:
return "metadata"
return "processing"
def _make_pp_hook(job_id: int):
"""Postprocessor hook: surface the current ffmpeg step so the bar shows a concrete label
(Merging / Embedding thumbnail / …) instead of freezing at 100% after the streams finish."""
def hook(d: dict) -> None:
if d.get("status") in ("started", "processing"):
_set_job(
job_id, phase=_pp_phase(d.get("postprocessor") or ""), speed_bps=None, eta_s=None
)
return hook
def _find_thumbnail(staging: Path, media: Path) -> Path | None:
for p in staging.iterdir():
if p != media and p.suffix.lower() in _THUMB_SUFFIXES:
return p
return None
def _produced_file(info: dict, staging: Path) -> Path:
"""The media file yt-dlp actually wrote.
`requested_downloads[0].filepath` is the authoritative answer on YouTube, but an arbitrary-URL
extractor may not fill it in at all — and `Path("")` is `Path(".")`, which *passes* `.exists()`,
so a missing value used to sail past the fallback and blow up two steps later (`with_name` on an
empty name: the BBC-news failure). Anything that isn't a real file counts as absent; then fall
back to the largest file left in staging that is neither a thumbnail nor one of yt-dlp's own
working files (see `_YTDLP_TEMP_RE`)."""
req = (info.get("requested_downloads") or [{}])[0]
fp = (
req.get("filepath") or req.get("_filename") or info.get("filepath") or info.get("_filename")
)
if fp:
produced = Path(str(fp))
if produced.is_file():
return produced
cands = [
p
for p in staging.iterdir()
if p.is_file()
and p.suffix.lower() not in _THUMB_SUFFIXES
and not _YTDLP_TEMP_RE.search(p.name)
]
if not cands:
raise RuntimeError("yt-dlp produced no output file")
return max(cands, key=lambda p: p.stat().st_size)
def _media_info(info: dict) -> dict:
"""Unwrap a playlist/multi_video extraction to the entry that carries the download.
A single non-YouTube page (a news article's video, a multi-rendition embed) can extract as a
wrapper whose own dict has no `requested_downloads` — the media lives on an entry. Pick the
FIRST entry that actually downloaded something: on a page with a skipped teaser in front of the
real video, entries[0] carries no file, and taking it blindly would label the produced file
with the wrong id/title/duration."""
entries = [e for e in (info.get("entries") or []) if e]
if not entries or info.get("requested_downloads"):
return info
chosen = next((e for e in entries if e.get("requested_downloads")), entries[0])
return {**info, **chosen}
def _extract_with_fallback(
job_id, asset_id, url, spec, staging, adapter, cookiefile=None, max_bytes=None
):
"""Download via yt-dlp using the source `adapter`'s client sets + options. For YouTube the adapter
supplies the primary player-client set then a POT-backed fallback (retried on a bot/DRM/format
error); other sources make a single attempt. Returns the info dict of the successful attempt.
`cookiefile` (S6) is the acting user's per-host cookies.txt, already gated by
`credentials.resolve_cookiefile`; passed to every attempt so the fallback stays authenticated.
`max_bytes` (SEC-13) is the owner's remaining storage budget, applied to every attempt."""
client_sets = adapter.client_sets()
outtmpl = str(staging / "%(id)s.%(ext)s")
last_exc: Exception | None = None
for i, clients in enumerate(client_sets):
opts = formats.build_ydl_opts(
spec,
outtmpl,
_make_progress_hook(job_id, asset_id),
extra=adapter.ydl_opts_extra(clients),
cookiefile=cookiefile,
max_bytes=max_bytes,
)
opts["postprocessor_hooks"] = [_make_pp_hook(job_id)]
_touch_job(job_id) # stall-watchdog heartbeat: extraction writes no progress, so a slow /
# multi-client-set fallback would otherwise cross the stall timeout with a stale updated_at.
# (Per-ATTEMPT only; a single extract_info that itself runs past the stall timeout is still
# killed — acceptable, as socket_timeout + extractor_retries bound one attempt well under it.)
try:
with yt_dlp.YoutubeDL(opts) as ydl:
return ydl.extract_info(url, download=True)
except yt_dlp.utils.DownloadError as exc:
last_exc = exc
if i < len(client_sets) - 1 and adapter.retriable(str(exc)):
log.info(
"job %s: clients %s failed (%s); retrying with fallback",
job_id,
clients,
str(exc)[:70],
)
for p in list(staging.iterdir()): # drop partials before the retry
try:
p.unlink()
except OSError:
pass
_set_job(job_id, progress=0, phase="downloading")
continue
raise
raise last_exc # unreachable (loop either returns or raises)
def _download_settings() -> tuple[str, int]:
"""Layout + retention days from the DB config (admin-overridable on the Configuration page),
falling back to the env defaults. Read here, not from `settings`, so an admin edit takes effect."""
with SessionLocal() as db:
return (
sysconfig.get_str(db, "download_layout"),
sysconfig.get_int(db, "download_retention_days"),
)
def _ensure_browser_playable(job_id: int, produced: Path, spec: dict, info: dict) -> Path:
"""Make an mp4-compat-profile download play in every browser: H.264 + AAC/MP3 in mp4. If the
download (whatever the source shipped) isn't already that, re-encode the offending stream(s) —
or just remux when the codecs are fine but the container isn't. **Scope:** only the mp4 compat
profile is normalized; an explicit `vcodec` or a non-mp4 custom profile is the user opting out
of the guarantee and is left as-is (so a `webm` profile can still ship VP9/Opus). Returns the
file to store (converted, or the original) and corrects `info`'s codec fields to match disk."""
if spec.get("container") != "mp4" or spec.get("vcodec"):
return produced
vcodec, acodec = editmod.probe_codecs(produced)
is_mp4 = produced.suffix.lower() == ".mp4"
needs, reenc_v, reenc_a = editmod.browser_transcode_flags(vcodec, acodec, is_mp4)
if not needs:
return produced
dest = produced.with_name(produced.stem + ".browser.mp4")
action = "re-encode" if (reenc_v or reenc_a) else "remux"
log.info(
"job %s: %s (v=%s a=%s mp4=%s) -> browser-safe mp4", job_id, action, vcodec, acodec, is_mp4
)
_set_job(job_id, phase="processing", progress=0, speed_bps=None, eta_s=None)
# Prefer the info duration; probe the file when the extractor didn't provide one, so a long
# re-encode still shows real progress instead of a frozen 0%.
total_s = int(info["duration"]) if info.get("duration") else editmod.probe_duration(produced)
editmod.run_ffmpeg(
editmod.build_browser_safe_cmd(
produced, dest, reenc_v, reenc_a, threads=editmod.encode_thread_cap()
),
total_s=total_s,
on_progress=_ffmpeg_progress_writer(job_id, "processing"),
should_cancel=_cancel_poll(job_id),
)
produced.unlink(missing_ok=True)
# Keep the stored asset metadata truthful about what's now on disk.
if reenc_v:
info["vcodec"] = "h264"
if reenc_a:
info["acodec"] = "aac"
return dest
def _download(
job_id: int, asset_id: int, source_kind: str, source_ref: str, spec: dict, user_id: int
) -> None:
staging = _staging_dir(asset_id)
cookiefile: Path | None = None
try:
if staging.exists():
shutil.rmtree(staging, ignore_errors=True)
staging.mkdir(parents=True, exist_ok=True)
_set_job(job_id, phase="downloading", progress=0)
adapter = adapters.resolve_adapter(source_kind, source_ref)
url = service.source_url(source_kind, source_ref)
# SEC-12, second half: the enqueue guard ran when the job was created, which may have been
# hours ago and against a different DNS answer. This is where the socket actually gets
# opened, so the check is repeated here and the job fails rather than fetching.
if source_kind == "url":
try:
urlguard.check_url(url)
except urlguard.BlockedUrl as e:
raise RuntimeError(f"Refusing to download from this address ({e.reason}).") from e
# S6: attach the acting user's per-host cookie ONLY when it's host-scoped to this URL AND
# this asset is that user's private, salted identity (the double gate lives in credentials).
remaining_bytes: int | None = None
with SessionLocal() as cdb:
asset_sig = cdb.execute(
select(MediaAsset.format_sig).where(MediaAsset.id == asset_id)
).scalar_one_or_none()
if asset_sig is not None:
cookiefile = credentials.resolve_cookiefile(
cdb, user_id, url, asset_sig, spec, staging
)
# SEC-13: what this user has left. `check_enqueue` only compares the CURRENT footprint
# against the cap — a download's size is unknown until it finishes, so a single job could
# previously blow through the cap by any amount. Handing the remainder to yt-dlp as
# `max_filesize` makes the format selector refuse an oversized file up front instead.
lim = quota.resolve(cdb, user_id)
if not lim.unlimited:
remaining_bytes = max(0, lim.max_bytes - quota.footprint(cdb, user_id))
info = _media_info(
_extract_with_fallback(
job_id,
asset_id,
url,
spec,
staging,
adapter,
cookiefile=str(cookiefile) if cookiefile else None,
max_bytes=remaining_bytes,
)
)
# Re-resolve now that yt-dlp's info reveals the true source (a bare/redirected url only
# identifies post-extraction) so the .nfo uniqueid type + uploader_url agree on one source.
adapter = adapters.resolve_adapter(source_kind, source_ref, info)
produced = _produced_file(info, staging)
produced = _ensure_browser_playable(job_id, produced, spec, info)
ext = produced.suffix.lstrip(".").lower()
meta = storage.MediaMeta(
video_id=info.get("id") or source_ref,
title=normalize_title(info.get("title")) or source_ref,
uploader=info.get("uploader") or info.get("channel") or "Unknown Channel",
upload_date=_parse_upload_date(info.get("upload_date")),
uniqueid_type=adapter.nfo_uniqueid_type(),
duration_s=int(info["duration"]) if info.get("duration") else None,
description=info.get("description"),
thumbnail_url=info.get("thumbnail"),
)
layout, retention_days = _download_settings()
rel = storage.rel_path(meta, ext, layout, asset_id=asset_id)
thumb = _find_thumbnail(staging, produced)
# Convert the raw thumbnail (webp/png/jpeg) to a real JPEG ourselves — robustly — for the
# poster + og:image sidecar, now that yt-dlp's fatal thumbnail convertor is gone. On failure
# this is None and write_sidecars writes no poster, so ensure_poster cuts a frame instead.
poster_jpg = editmod.thumbnail_to_jpg(thumb, staging / "poster.jpg")
storage.place_file(produced, settings.download_root, rel)
nfo_ok = storage.write_sidecars(settings.download_root, rel, meta, poster_jpg)
final = storage.abs_path(settings.download_root, rel)
size = final.stat().st_size if final.exists() else None
expires = datetime.now(timezone.utc) + timedelta(days=retention_days)
with SessionLocal() as db:
asset = db.get(MediaAsset, asset_id)
if asset:
asset.status = "ready"
asset.rel_path = rel
asset.size_bytes = size
asset.duration_s = meta.duration_s
# Codecs/dims come from a PROBE of the finished file — the ground truth — NOT yt-dlp's
# `info` dict, whose codec fields are absent for some sources (Facebook among them):
# deriving media_kind from those nulls misclassified a real H.264 video as a
# download-only 'file' with no in-app play/edit. Same probe the upload ingest uses.
asset.vcodec, asset.acodec, asset.width, asset.height = probe.resolve_media_facts(
final, info
)
asset.container = ext
asset.media_kind = mediakind.derive(asset.vcodec, asset.acodec)
asset.title = meta.title
asset.uploader = meta.uploader
asset.uploader_url = adapter.uploader_url(info)
asset.upload_date = meta.upload_date
asset.thumbnail_url = meta.thumbnail_url
# Record a self-hosted poster for every download: it's the reliable link-preview
# (og:image) source — a remote thumbnail, esp. Facebook's signed CDN URL, expires
# and can't be relied on cross-origin. write_sidecars already wrote <base>.jpg from
# the thumbnail; ensure_poster returns that, or cuts a frame if there was none.
asset.poster_path = editmod.ensure_poster(asset, settings.download_root)
asset.source_webpage_url = info.get("webpage_url")
asset.nfo_written = nfo_ok
asset.error = None
asset.last_access_at = datetime.now(timezone.utc)
asset.expires_at = expires
job = db.get(DownloadJob, job_id)
# Capture the owner before commit expires the row (avoids a refresh SELECT just to notify).
owner_id = job.user_id if job else None
fields = {
"status": JobStatus.DONE,
"progress": 100,
"phase": None,
"speed_bps": None,
"eta_s": None,
}
if job and not job.display_name and meta.title:
# display_name is VARCHAR(255) — clip a long title (see _fill_asset_meta_early).
fields["display_name"] = meta.title[:255]
# Atomic terminal write: finalizes ONLY while the row is still running, so a child that
# finishes just after a route cancel/pause can't resurrect it (see finalize_if_running).
finalized = service.finalize_if_running(db, job_id, **fields)
db.commit()
if finalized:
_notify_download_done(db, owner_id, meta.title, job_id, kind="download")
log.info("job %s done: %s", job_id, rel)
except (_Aborted, editmod.EditAborted):
# Paused/canceled mid-download or mid-transcode: free the asset for a later retry; keep the
# job's status (the route set it to paused/canceled). ref_count is adjusted by the route.
_reset_asset_pending(asset_id)
log.info("job %s aborted (pause/cancel)", job_id)
except Exception as exc: # noqa: BLE001 — surface any failure to the user, keep worker alive
msg = str(exc)[:500]
code = dlerrors.classify(msg)
# SEC-12: for a user-supplied URL, a transport-level failure text distinguishes "connection
# refused" from "HTTP Error 401" from "timed out" per host:port — which is a port scanner
# with extra steps, since the raw text is shown to the user behind the details disclosure.
# The urlguard above stops it aiming at our own network; this stops the remaining readout.
# Only the network class, and only for `url` jobs: a YouTube job has no user-chosen host, and
# every other class (login_required, geo_blocked, drm, …) is real, useful diagnosis.
if source_kind == "url" and code == "network":
msg = "The server could not reach that address."
with SessionLocal() as db:
asset = db.get(MediaAsset, asset_id)
if asset:
asset.status = "error"
asset.error = msg
# Atomic fail: only while still running, so a route-set cancel/pause is never overwritten
# with `error` (error also holds the asset → would re-open the double-release class).
service.finalize_if_running(
db,
job_id,
status=JobStatus.ERROR,
error=msg,
error_code=code,
phase=None,
)
db.commit()
log.warning("job %s failed: %s", job_id, msg)
finally:
# Unlink the decrypted cookie file explicitly (the rmtree below removes the whole staging
# tree too, but never leave a plaintext session cookie on disk a moment longer than needed).
if cookiefile is not None:
cookiefile.unlink(missing_ok=True)
shutil.rmtree(staging, ignore_errors=True)
def _fail_edit(job_id: int, asset_id: int, msg: str) -> None:
with SessionLocal() as db:
asset = db.get(MediaAsset, asset_id)
if asset:
asset.status = "error"
asset.error = msg
# Atomic fail: only while still running (see the download error path).
service.finalize_if_running(
db,
job_id,
status=JobStatus.ERROR,
error=msg,
error_code=dlerrors.classify(msg),
phase=None,
)
db.commit()
log.warning("edit job %s failed: %s", job_id, msg)
def _process_edit(job_id: int, asset_id: int) -> None:
"""Produce a per-user trim/crop clip from the source asset's downloaded file via ffmpeg."""
with SessionLocal() as db:
job = db.get(DownloadJob, job_id)
src = db.get(MediaAsset, job.source_asset_id) if job and job.source_asset_id else None
edit_spec = dict(job.edit_spec or {}) if job else {}
user_id = job.user_id if job else None
src_ready = src is not None and src.status == "ready" and bool(src.rel_path)
src_rel = src.rel_path if src else None
src_w, src_h, src_dur = (
(src.width, src.height, src.duration_s) if src else (None, None, None)
)
if not src_ready or not src_rel:
_fail_edit(job_id, asset_id, "The source download is no longer available.")
return
src_path = storage.abs_path(settings.download_root, src_rel)
if not src_path.exists():
_fail_edit(job_id, asset_id, "The source file is missing.")
return
src_ext = src_path.suffix.lstrip(".").lower() or "mp4"
crop = editmod.has_crop(edit_spec)
out_ext = "mp4" if editmod.needs_reencode(edit_spec) else src_ext
total_s = editmod.clip_duration(edit_spec, src_dur) or src_dur or 0
staging = _edit_staging_dir(asset_id)
try:
if staging.exists():
shutil.rmtree(staging, ignore_errors=True)
staging.mkdir(parents=True, exist_ok=True)
dest_staging = staging / f"out.{out_ext}"
_set_job(job_id, phase="editing", progress=0, speed_bps=None, eta_s=None)
if edit_spec.get("segments"):
cmd, prep = editmod.build_concat_plan(
src_path, dest_staging, edit_spec, out_ext, staging
)
for p, content in prep.items():
p.write_text(content, encoding="utf-8")
else:
cmd = editmod.build_edit_cmd(src_path, dest_staging, edit_spec, out_ext)
editmod.run_ffmpeg(
cmd,
total_s,
on_progress=_ffmpeg_progress_writer(job_id, "editing"),
should_cancel=_cancel_poll(job_id),
)
if not dest_staging.exists():
raise RuntimeError("ffmpeg produced no output file")
rel = storage.edit_rel_path(user_id, asset_id, out_ext)
storage.place_file(dest_staging, settings.download_root, rel)
final = storage.abs_path(settings.download_root, rel)
size = final.stat().st_size if final.exists() else None
_, retention_days = _download_settings()
expires = datetime.now(timezone.utc) + timedelta(days=retention_days)
with SessionLocal() as db:
asset = db.get(MediaAsset, asset_id)
if asset:
asset.status = "ready"
asset.rel_path = rel
asset.size_bytes = size
asset.container = out_ext
asset.duration_s = total_s or asset.duration_s
if crop:
asset.width = edit_spec["crop"]["w"]
asset.height = edit_spec["crop"]["h"]
else:
asset.width, asset.height = src_w, src_h
asset.error = None
asset.last_access_at = datetime.now(timezone.utc)
asset.expires_at = expires
job = db.get(DownloadJob, job_id)
# Capture owner + title before commit expires the rows (avoids a refresh SELECT).
owner_id = job.user_id if job else None
dl_title = asset.title if asset else None
# Atomic terminal write (see the download path): don't resurrect a route-stopped job.
finalized = service.finalize_if_running(
db, job_id, status=JobStatus.DONE, progress=100, phase=None
)
db.commit()
if finalized:
_notify_download_done(db, owner_id, dl_title, job_id, kind="edit")
log.info("edit job %s done: %s", job_id, rel)
except editmod.EditAborted:
# Paused/canceled mid-encode: free the asset for a later retry (ref_count is the route's job).
_reset_asset_pending(asset_id)
log.info("edit job %s aborted (pause/cancel)", job_id)
except Exception as exc: # noqa: BLE001 — surface the failure, keep the worker alive
_fail_edit(job_id, asset_id, str(exc)[:500])
finally:
shutil.rmtree(staging, ignore_errors=True)