Files
FabledCurator/backend/app/tasks/ml.py
T
bvandeusen e3cdd0f92b feat(import-resilience L3): subprocess-isolated probes for video + archive
Layer 3 — prevent the hard worker crash rather than just recovering from
it. The realistic process-crash vectors (operator's observed slow/heavy
tasks) are video decode and archive extraction; images decode in-process
and Pillow raises-and-skips cleanly, and a subprocess per image would
wreck deep-scan throughput, so images are intentionally not probed.

New backend/app/utils/safe_probe.py (leaf module, lazy heavy imports so
the spawned child stays light):

- probe_video(path): validates the container + first video stream via
  ffprobe (a separate binary — a decoder crash kills only ffprobe, not
  the worker). Returns width/height, which the importer didn't capture
  for videos before. crashed=True only on ffprobe timeout.
- probe_archive(path): an uncompressed-size bomb guard
  (MAX_ARCHIVE_UNCOMPRESSED_BYTES = 4 GiB) plus the format integrity
  test (zipfile.testzip / rarfile.testrar / py7zr.test) run in a
  spawned child process. A decompression-bomb OOM or native-lib
  segfault on a malformed archive shows up as a non-zero child exit
  code → crashed=True, never a dead worker.

ProbeResult.crashed distinguishes a HARD failure (subprocess killed /
timed out — the poison-pill signature → caller returns terminal
'failed') from a CLEAN rejection (corrupt-but-handled, bomb cap,
integrity mismatch → caller's choice of skipped/attached).

Wired:
- importer._import_media video branch: probe_video before the pipeline;
  crash → failed, clean reject → invalid_image skip, ok → capture dims.
- importer._import_archive: probe_archive before extract_archive; crash
  → failed, clean reject → still preserve the archive as a
  PostAttachment (matches extract_archive's fail-soft contract).
- ml.tag_and_embed video branch: probe_video before sampling 10 frames,
  so a corrupt video is rejected (status='bad_video') instead of
  crashing the ml-worker on frame decode.

Tests (test_safe_probe.py): valid/corrupt zip via probe_archive, direct
_inspect_archive size+integrity, in-process _archive_probe_target bomb
guard (monkeypatch can't reach a spawned child, so the target is called
directly), and a non-video → ok=False that's robust to ffprobe presence
in CI.
2026-05-28 00:01:32 -04:00

360 lines
12 KiB
Python

"""ML Celery tasks: per-image inference, backfill discovery, centroid
recompute, allowlist auto-apply, model self-heal.
All run on the ml-worker (queue 'ml') except recompute_centroids and
apply_allowlist_tags sweeps which are 'maintenance' lane. Sync sessions
(Celery workers are sync processes), same pattern as FC-2a tasks.
"""
from pathlib import Path
from sqlalchemy import select
from sqlalchemy.exc import DBAPIError, OperationalError
from ..celery_app import celery
from ..models import ImageRecord, MLSettings
from ._sync_engine import sync_session_factory as _sync_session_factory
IMAGES_ROOT = Path("/images")
VIDEO_EXTS = {".mp4", ".mov", ".avi", ".mkv", ".webm", ".m4v", ".wmv", ".flv"}
def _is_video(path: Path) -> bool:
return path.suffix.lower() in VIDEO_EXTS
@celery.task(
name="backend.app.tasks.ml.tag_and_embed",
bind=True,
autoretry_for=(OperationalError, DBAPIError, OSError),
retry_backoff=5,
retry_backoff_max=60,
retry_jitter=True,
max_retries=3,
# Sized for the video branch: sample 10 frames, run tagger +
# embedder on each (≈20 GPU ops vs 2 for an image). A loaded
# ml-worker can take 5-10 min on a long video; bumped from
# 5min/7min on 2026-05-28 after operator-flagged image 6288 (a
# .mp4) hit the recovery sweep at 5 min while still legitimately
# processing. Image runs return in seconds; the bump doesn't
# affect their UX.
soft_time_limit=900, # 15 min
time_limit=1200, # 20 min hard
)
def tag_and_embed(self, image_id: int) -> dict:
"""Run Camie + SigLIP on one image; store predictions + embedding;
then enqueue per-image allowlist application.
Video: sample frames between 10% and 90% of duration (VIDEO_ML_FRAMES,
default 10). Max-pool tagger confidences across frames, mean-pool the
SigLIP embeddings. On no-frames returns status='no_frames' (not an error).
"""
import os
from ..services.ml.embedder import get_embedder
from ..services.ml.tagger import get_tagger
SessionLocal = _sync_session_factory()
with SessionLocal() as session:
record = session.get(ImageRecord, image_id)
if record is None:
return {"status": "missing", "image_id": image_id}
settings = session.execute(
select(MLSettings).where(MLSettings.id == 1)
).scalar_one()
src = Path(record.path)
if not src.is_file():
return {"status": "file_missing", "image_id": image_id}
tagger = get_tagger()
embedder = get_embedder()
if _is_video(src):
# Layer-3 isolation: ffprobe (a separate process) validates
# the container before we burn ~20 GPU ops sampling frames
# from it. A corrupt video that would crash the frame
# decoder is rejected cleanly here instead of taking down
# the ml-worker. Operator-flagged 2026-05-28.
from ..utils import safe_probe
vprobe = safe_probe.probe_video(src)
if not vprobe.ok:
return {
"status": "bad_video", "image_id": image_id,
"reason": vprobe.reason,
}
frames = _sample_video_frames(
src, int(os.environ.get("VIDEO_ML_FRAMES", "10"))
)
if not frames:
return {"status": "no_frames", "image_id": image_id}
preds = _maxpool_predictions([tagger.infer(f) for f in frames])
import numpy as np
embedding = np.mean(
[embedder.infer(f) for f in frames], axis=0
).astype("float32")
for f in frames:
f.unlink(missing_ok=True)
else:
raw = tagger.infer(src)
preds = {
name: {"category": p.category, "confidence": p.confidence}
for name, p in raw.items()
}
embedding = embedder.infer(src)
record.tagger_predictions = preds
record.tagger_model_version = settings.tagger_model_version
record.siglip_embedding = embedding.tolist()
record.siglip_model_version = settings.embedder_model_version
session.add(record)
session.commit()
apply_allowlist_tags.delay(image_id=image_id)
return {"status": "ok", "image_id": image_id, "tags": len(preds)}
def _sample_video_frames(src: Path, n: int) -> list[Path]:
"""Extract n frames evenly between 10% and 90% of duration via ffmpeg.
Returns temp file paths (caller deletes). Empty list on failure."""
import json
import subprocess
import tempfile
try:
probe = subprocess.run(
[
"ffprobe", "-v", "quiet", "-print_format", "json",
"-show_format", str(src),
],
check=True, capture_output=True, timeout=30,
)
duration = float(json.loads(probe.stdout)["format"]["duration"])
except Exception:
return []
if duration <= 0:
return []
start, end = duration * 0.10, duration * 0.90
step = (end - start) / max(n - 1, 1)
out: list[Path] = []
tmpdir = Path(tempfile.mkdtemp(prefix="fc_vid_"))
for i in range(n):
ts = start + i * step
dest = tmpdir / f"frame_{i:02d}.jpg"
try:
subprocess.run(
[
"ffmpeg", "-ss", f"{ts:.2f}", "-i", str(src),
"-frames:v", "1", "-q:v", "3", "-y", str(dest),
],
check=True, capture_output=True, timeout=60,
)
if dest.is_file():
out.append(dest)
except Exception:
continue
return out
def _maxpool_predictions(per_frame: list[dict]) -> dict:
"""Aggregate per-frame {name: TagPrediction} dicts by max confidence."""
merged: dict[str, dict] = {}
for frame_preds in per_frame:
for name, p in frame_preds.items():
cur = merged.get(name)
if cur is None or p.confidence > cur["confidence"]:
merged[name] = {
"category": p.category,
"confidence": p.confidence,
}
return merged
@celery.task(name="backend.app.tasks.ml.backfill", bind=True)
def backfill(self) -> int:
"""Enqueue tag_and_embed for images missing predictions/embeddings for
the current model versions. Keyset pagination by id ASC (restart-safe).
"""
SessionLocal = _sync_session_factory()
enqueued = 0
last_id = 0
with SessionLocal() as session:
settings = session.execute(
select(MLSettings).where(MLSettings.id == 1)
).scalar_one()
while True:
rows = session.execute(
select(ImageRecord.id)
.where(ImageRecord.id > last_id)
.where(
(ImageRecord.tagger_predictions.is_(None))
| (
ImageRecord.tagger_model_version
!= settings.tagger_model_version
)
| (ImageRecord.siglip_embedding.is_(None))
| (
ImageRecord.siglip_model_version
!= settings.embedder_model_version
)
)
.order_by(ImageRecord.id.asc())
.limit(500)
).scalars().all()
if not rows:
break
for image_id in rows:
tag_and_embed.delay(image_id)
enqueued += 1
last_id = rows[-1]
return enqueued
@celery.task(name="backend.app.tasks.ml.apply_allowlist_tags", bind=True)
def apply_allowlist_tags(self, tag_id: int | None = None,
image_id: int | None = None) -> int:
"""Retroactively apply allowlisted tags.
Modes:
- tag_id only : scan all images for this tag.
- image_id only : scan all allowlisted tags for this image.
- both : just the (image, tag) pair.
- neither : full sweep (daily beat).
Skips: already-applied, rejected (tag_suggestion_rejection), or
confidence below the tag's allowlist min_confidence. Applied with
source='ml_auto'.
"""
from sqlalchemy import and_
from sqlalchemy import select as sa_select
from sqlalchemy.dialects.postgresql import insert as pg_insert
from ..models import TagAllowlist, TagSuggestionRejection
from ..models.tag import image_tag
SessionLocal = _sync_session_factory()
applied = 0
with SessionLocal() as session:
allow_rows = session.execute(
sa_select(TagAllowlist.tag_id, TagAllowlist.min_confidence)
if tag_id is None
else sa_select(
TagAllowlist.tag_id, TagAllowlist.min_confidence
).where(TagAllowlist.tag_id == tag_id)
).all()
allow = {r[0]: r[1] for r in allow_rows}
if not allow:
return 0
img_query = sa_select(
ImageRecord.id, ImageRecord.tagger_predictions
).where(ImageRecord.tagger_predictions.is_not(None))
if image_id is not None:
img_query = img_query.where(ImageRecord.id == image_id)
for img_id, preds in session.execute(img_query).all():
preds = preds or {}
for a_tag_id, min_conf in allow.items():
exists = session.execute(
sa_select(image_tag.c.tag_id).where(
and_(
image_tag.c.image_record_id == img_id,
image_tag.c.tag_id == a_tag_id,
)
)
).scalar_one_or_none()
if exists is not None:
continue
rej = session.get(
TagSuggestionRejection, (img_id, a_tag_id)
)
if rej is not None:
continue
from ..models import Tag
tag = session.get(Tag, a_tag_id)
if tag is None:
continue
conf = _confidence_for_tag(session, tag, preds)
if conf is None or conf < min_conf:
continue
stmt = pg_insert(image_tag).values(
image_record_id=img_id,
tag_id=a_tag_id,
source="ml_auto",
)
stmt = stmt.on_conflict_do_nothing(
index_elements=["image_record_id", "tag_id"]
)
session.execute(stmt)
applied += 1
session.commit()
return applied
def _confidence_for_tag(session, tag, preds: dict) -> float | None:
"""Highest confidence among predictions that resolve to `tag` —
either the prediction name equals the tag name, or an alias maps
(prediction name, category) -> tag.id.
"""
from sqlalchemy import select as sa_select
from ..models import TagAlias
best: float | None = None
direct = preds.get(tag.name)
if direct is not None:
best = float(direct.get("confidence", 0.0))
alias_rows = session.execute(
sa_select(TagAlias.alias_string, TagAlias.alias_category).where(
TagAlias.canonical_tag_id == tag.id
)
).all()
for alias_string, alias_category in alias_rows:
p = preds.get(alias_string)
if p is None:
continue
if p.get("category") != alias_category:
continue
c = float(p.get("confidence", 0.0))
if best is None or c > best:
best = c
return best
@celery.task(name="backend.app.tasks.ml.recompute_centroid", bind=True)
def recompute_centroid(self, tag_id: int) -> bool:
import asyncio
from ..extensions import get_session
from ..services.ml.centroids import CentroidService
async def _run() -> bool:
async with get_session() as session:
svc = CentroidService(session)
result = await svc.recompute_for_tag(tag_id)
await session.commit()
return result
return asyncio.run(_run())
@celery.task(name="backend.app.tasks.ml.recompute_centroids", bind=True)
def recompute_centroids(self) -> int:
"""Daily: find drifted centroids, enqueue recompute_centroid for each."""
import asyncio
from ..extensions import get_session
from ..services.ml.centroids import CentroidService
async def _list() -> list[int]:
async with get_session() as session:
return await CentroidService(session).list_drifted()
drifted = asyncio.run(_list())
for tid in drifted:
recompute_centroid.delay(tid)
return len(drifted)