Files
siftlode/backend/app/downloads/errors.py
T
peter e1d325b942 fix(downloads): a download larger than the space left says so, not "processing failed"
yt-dlp refuses a file announced over `max_filesize` by logging one line and returning with no file
(measured, and pinned in test_formats against a local server): the worker found no output and
failed the job as `postprocess`. `formats.watching_size_cap` now sees that line through our yt-dlp
logger, and the download (and, should it ever happen, a YouTube clip's range fetch) fails as the
owner's refusal with DOWNLOAD_TOO_BIG_MESSAGE, classified `quota_exceeded`. The download's quota
copy says it does not fit in what is left — true at a full cap too — instead of "Storage full".
A pre-existing type error the change touched is fixed (baseline down by one).
2026-10-10 21:56:47 +02:00

329 lines
17 KiB
Python

"""Classify a raw yt-dlp / ffmpeg failure string into a stable category code — and, where a site's
failure has been measured, into that site's entry of the failure catalog.
The worker stores the raw exception text (truncated) for technical detail, but a raw
`ERROR: [youtube] <id>: Private video. Sign in…` is noise to a user. `classify()` maps that text
to one of a small set of category codes; the frontend turns the code into a localized, human
explanation (and decides whether a retry makes sense). The raw text stays available behind a
"details" disclosure. This is the same string-matching approach the worker already trusts for
`_RETRIABLE_MARKERS` — kept here as the single source of truth for "what kind of failure is this".
**The failure catalog** (`_CATALOG`). A category is generic: "Sign-in required" cannot tell a
Facebook user that the cookie they already gave was refused, and yt-dlp words several different
Facebook walls identically (`Cannot parse data`). A catalog entry is scoped to ONE host and may also
depend on whether a cookie was attached and on the kind of link, and names a `detail` code the UI has
its own sentence for — why it failed on that site, and what the user can do. `diagnose()` tries the
catalog first and falls back to the category. How an entry is added, every time a failure is reported:
1. reproduce it on dev (with and without the user's cookie) and keep the verbatim yt-dlp text;
2. add the entry below, scoped as narrowly as the measurement allows (a marker that is yt-dlp's
generic wording for every site must never match without its host; a marker another module also
decides on — the Facebook Chrome retry's FACEBOOK_PARSE_WALL — is imported, never retyped);
3. pin the real text in `tests/test_download_errors.py`;
4. add `downloads.errors.fail.catalog.<detail>.{short,body}` in EN and HU (a contract test checks it;
the group is not called `detail`, which `actionErrors.contract` reads as a raw `HttpError.detail`).
"""
from collections.abc import Callable
from dataclasses import dataclass
from typing import NamedTuple
from app.downloads.adapters import (
FACEBOOK_PARSE_WALL,
POST_NOT_SHOWN_MESSAGE,
POST_WITHOUT_VIDEO_MESSAGE,
facebook_group_post_id,
)
from app.downloads.credentials import host_key_for_url
# Worker-authored strings that this module owns because each is coupled to `_RULES`.
#
# QUOTA_FULL_MESSAGE and the three *_TOO_BIG_MESSAGEs are raised by the worker and must classify
# back to `quota_exceeded`; their rules below match a fragment of each, and test_download_errors pins
# each one, because a message and its rule drifting apart is exactly how a
# category silently becomes unreachable.
#
# NETWORK_REDACTED_MESSAGE REPLACES a message after classification (`user_error_text`). It is written
# to the shared asset too, and a second job that inherits that failed asset re-diagnoses the stored
# text (`worker._process_job`), so it has a rule of its own that gives the category back.
#
# Other worker-raised texts are still inline literals at their raise sites. The ffmpeg ones and
# "produced no output file" have markers here; the urlguard refusal deliberately has none and
# classifies as `unknown` — it is a refusal, not a diagnosis, and no category would say more.
#
# A source adapter's verdicts on a link (`SourceAdapter.resolve_url`) are adapters.py's
# constants, imported above; each has a rule below that gives its category back, and a catalog entry
# that gives the site's sentence.
QUOTA_FULL_MESSAGE = "Your download storage is full — free up space, then try again."
# A download, a cut clip, or an upload's converted file, held to the space left, which is not zero:
# "full" would be untrue. All three classify by the one phrase they share.
DOWNLOAD_TOO_BIG_MESSAGE = (
"The video is larger than the download storage you have left — free up space, then try again."
)
CLIP_TOO_BIG_MESSAGE = (
"The clip is larger than the download storage you have left — "
"free up space or cut a shorter clip, then try again."
)
CONVERTED_TOO_BIG_MESSAGE = (
"The converted file is larger than the download storage you have left — "
"free up space, then try again."
)
UPLOAD_MISSING_MESSAGE = "The uploaded file is missing."
NETWORK_REDACTED_MESSAGE = "The server could not reach that address."
# (marker, category) — first match wins, so order most-specific → most-general. Matching is
# case-insensitive on a substring, against the raw yt-dlp/ffmpeg message.
_RULES: tuple[tuple[str, str], ...] = (
# Our own refusal: the worker found the user already at their storage cap (SEC-13). Placed
# first — it is our wording, so it can never be a false match on an upstream message.
("download storage is full", "quota_exceeded"),
("larger than the download storage you have left", "quota_exceeded"),
# Our own redaction of a transport failure (see NETWORK_REDACTED_MESSAGE) — our wording too.
(NETWORK_REDACTED_MESSAGE.lower(), "network"),
# Our own verdicts on a post link (adapters.py) — our wording too: its page holds no single video,
# or the site answered the signed-in read with something that is not the post at all.
(POST_WITHOUT_VIDEO_MESSAGE.lower(), "format_unavailable"),
(POST_NOT_SHOWN_MESSAGE.lower(), "login_required"),
# Login / age / members / bot-check — the user must be signed in (we deliberately are not).
("sign in to confirm your age", "login_required"),
("confirm your age", "login_required"),
("sign in to confirm you're not a bot", "login_required"),
("not a bot", "login_required"),
("sign in to confirm", "login_required"),
("members-only", "login_required"),
("available to this channel's members", "login_required"),
("join this channel", "login_required"),
("this video is only available to", "login_required"),
# Some extractors (e.g. Reddit) gate content behind a logged-in account: "Account
# authentication is required." — an auth wall we deliberately don't cross, not a transient error.
("authentication is required", "login_required"),
# Closed-group / private-post auth walls (Facebook groups, Instagram private, …). yt-dlp phrases
# these many ways; the common thread is "you must be signed in" or its own suggestion to supply
# cookies. Treating the cookie suggestion as an auth signal is what makes a login-walled link read
# honestly (and stay non-retryable) when the acting user has no usable cookie for that host.
("log in to", "login_required"),
("login required", "login_required"),
("you must be logged in", "login_required"),
("only available for registered users", "login_required"),
("use --cookies", "login_required"),
("--cookies-from-browser", "login_required"),
# Geo-restricted.
("in your country", "geo_blocked"),
("available in your location", "geo_blocked"),
("not available from your location", "geo_blocked"),
("geo restricted", "geo_blocked"),
# An edit's source download went away — our own wording, and MORE specific than the generic
# "no longer available" below, so it must be matched first.
("source download is no longer available", "source_missing"),
# An upload's original went away before its conversion ran — our wording (UPLOAD_MISSING_MESSAGE).
(UPLOAD_MISSING_MESSAGE.lower().rstrip("."), "upload_missing"),
("source file is missing", "source_missing"),
# Private / deleted / removed / terminated.
("private video", "unavailable"),
("video unavailable", "unavailable"),
("no longer available", "unavailable"),
("has been removed", "unavailable"),
("removed by the uploader", "unavailable"),
("account associated with this video has been terminated", "unavailable"),
("this video is not available", "unavailable"),
("this video has been removed", "unavailable"),
# yt-dlp doesn't support this site at all ("Unsupported URL: …") — distinct from an auth wall on a
# supported site. Non-retryable: no cookie or retry can make an unsupported host downloadable.
("unsupported url", "unsupported_host"),
("no video could be found in this url", "unsupported_host"),
# DRM.
("drm protected", "drm"),
("drm-protected", "drm"),
# No usable media format.
("requested format is not available", "format_unavailable"),
("only images are available", "format_unavailable"),
("no video formats found", "format_unavailable"),
("unable to extract", "format_unavailable"),
# Our own post-processing (ffmpeg) step failed.
("ffmpeg failed", "postprocess"),
("ffmpeg stalled", "postprocess"),
("postprocessing", "postprocess"),
("produced no output file", "postprocess"),
("no output file", "postprocess"),
# Network / transport.
("unable to download", "network"),
("http error", "network"),
("timed out", "network"),
("read timed out", "network"),
("temporary failure in name resolution", "network"),
("connection reset", "network"),
("connection refused", "network"),
("failed to resolve", "network"),
)
class Diagnosis(NamedTuple):
"""What a failure was: the generic `code` (category) and, when a catalog entry matched, its
host-specific `detail`."""
code: str
detail: str | None = None
@dataclass(frozen=True)
class _Entry:
"""One measured failure of one site. It matches when the download URL belongs to `host`
(`credentials.SUPPORTED_HOSTS`), every one of `markers` is in the message, the cookie state is
`cookie` (None: either), and — when `link` is given — it recognises the URL (a truthy result). A
link predicate is the adapter's own, so the catalog and the download agree on what a link is."""
host: str
markers: tuple[str, ...]
code: str
detail: str
cookie: bool | None = None
link: Callable[[str], object] | None = None
_CATALOG: tuple[_Entry, ...] = (
# Facebook answers a signed-out client with a page yt-dlp cannot parse — an 18+ reel, a closed
# group's post (measured 2026-09-13: prod jobs 145, 156, 256 download once the owner's cookie is
# attached). "Cannot parse data" is yt-dlp's generic wording for a broken extractor on EVERY site,
# which is why the entry is scoped to Facebook and never becomes a general rule.
_Entry(
host="facebook",
markers=("[facebook]", FACEBOOK_PARSE_WALL),
code="login_required",
detail="facebook.login_wall",
cookie=False,
),
# The same text WITH a cookie: an expired / signed-out cookie, or a page that also needs
# impersonation (prod job 257). Telling this user to add cookies would be wrong — they have.
_Entry(
host="facebook",
markers=("[facebook]", FACEBOOK_PARSE_WALL),
code="login_required",
detail="facebook.cookie_rejected",
cookie=True,
),
# A group post read with a cookie that Facebook answered with its login page (measured with a
# refused cookie: no post id anywhere on the page) — the same refused cookie, found by the adapter.
_Entry(
host="facebook",
markers=(POST_NOT_SHOWN_MESSAGE.lower(),),
code="login_required",
detail="facebook.cookie_rejected",
cookie=True,
),
# A group post with no single video of its own. With a cookie the adapter reads the post's page
# and says so itself (POST_WITHOUT_VIDEO_MESSAGE); without one yt-dlp is given the post link and
# answers "No video formats found" (measured on prod jobs 66 and 145, whose videos are reshared
# clips). With a cookie yt-dlp only ever gets the post's VIDEO link, so the same text there is about
# that video, not the post — the category says it. Only for group post links (the adapter's own
# test of one): a reel with no formats is a different failure.
_Entry(
host="facebook",
markers=(POST_WITHOUT_VIDEO_MESSAGE.lower(),),
code="format_unavailable",
detail="facebook.group_post_video",
link=facebook_group_post_id,
),
_Entry(
host="facebook",
markers=("[facebook]", "no video formats found"),
code="format_unavailable",
detail="facebook.group_post_video",
cookie=False,
link=facebook_group_post_id,
),
# YouTube gates INDIVIDUAL videos behind "Sign in to confirm you're not a bot" (measured on prod
# job 273, a festival set: all 12 of yt-dlp's player clients fail on that one video while its
# neighbours download fine, the POT sidecar is live and answering, and the newest yt-dlp fails
# identically — so this is the video's own signed-out gate, not a broken stack or a stale yt-dlp).
# The marker is quote-agnostic on purpose: YouTube writes the apostrophe as U+2019, so
# "you're not a bot" with a straight quote never matches the real text.
_Entry(
host="youtube",
markers=("[youtube]", "not a bot"),
code="login_required",
detail="youtube.bot_wall",
cookie=False,
),
# The same wall WITH a cookie. Not yet reproduced with a real YouTube cookie (this user's first
# one is being added now) — but "add cookies" is provably the wrong advice for someone who has,
# and yt-dlp names the likeliest cause itself: "The provided YouTube account cookies are no
# longer valid. They have likely been rotated in the browser as a security measure."
_Entry(
host="youtube",
markers=("[youtube]", "not a bot"),
code="login_required",
detail="youtube.cookie_rejected",
cookie=True,
),
# The same gate one step later: the player response comes back, and then the CDN refuses the
# stream itself ("unable to download video data: HTTP Error 403"). Measured 2026-09-16 on the
# very same video, ~90 minutes after it was answering with the bot message — signed out it
# 403'd on every attempt; with the owner's cookie attached it downloaded in full (519 MB). So
# the category this text carries generically, `network`, is a lie here: nothing was wrong with
# the network. Scoped to a cookie-less YouTube download, where that is what we measured.
_Entry(
host="youtube",
markers=("unable to download video data", "403"),
code="login_required",
detail="youtube.media_forbidden",
cookie=False,
),
)
def classify(msg: str | None) -> str:
"""Return a category code for a raw failure message (``"unknown"`` if nothing matches)."""
if not msg:
return "unknown"
low = msg.lower()
for marker, category in _RULES:
if marker in low:
return category
return "unknown"
def classify_conversion(msg: str | None) -> str:
"""The category of an upload's failed conversion. The generic ffmpeg categories speak of a
download ("the video downloaded but…"), which an upload never was: a failed encode or an
unrecognised failure of one is `convert_failed`; a category of its own (a full quota, a missing
original) stays as it is."""
code = classify(msg)
return "convert_failed" if code in ("postprocess", "unknown") else code
def diagnose(
msg: str | None, *, url: str | None = None, cookie_attached: bool = False
) -> Diagnosis:
"""The catalog entry for this failure of this link, else just its category (see the module doc).
`url` is the address yt-dlp was given; `cookie_attached` whether the acting user's cookie went
with it. Without a URL only the category can be known."""
host = host_key_for_url(url) if msg and url else None
if host is not None:
low = msg.lower() # type: ignore[union-attr] — `host` is only set when `msg` is truthy
for e in _CATALOG:
if (
e.host == host
and all(m in low for m in e.markers)
and (e.cookie is None or e.cookie == cookie_attached)
and (e.link is None or e.link(url)) # type: ignore[arg-type] — as `msg` above
):
return Diagnosis(e.code, e.detail)
return Diagnosis(classify(msg))
def user_error_text(source_kind: str, msg: str, code: str) -> str:
"""The failure text to STORE on the job, given the raw message and its category.
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. `urlguard`
stops the fetch 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. A separate
function rather than an inline branch in the worker so it can be pinned by a test — the raw
text leaking back is a security regression that would otherwise pass a green suite."""
if source_kind == "url" and code == "network":
return NETWORK_REDACTED_MESSAGE
return msg