CubeComming #804: importing Coldplay "Yellow" (the 269s Parachutes album track,
correctly tagged) was quarantined — "Duration mismatch: file is 269.2s, expected
266.0s (drift 3.2s > tolerance 3.0s)". The expected 266s came from a re-resolved
*single* edition, not the file's actual album. The duration-agreement integrity
check exists to catch truncated/wrong slskd TRANSFERS — but a manual import is
the user's own already-tagged file being sorted, so checking it against a
re-resolved release just manufactures false quarantines.
Fix: both manual-import paths (singles + album) now mark the context
is_local_import; the integrity check skips the duration-agreement leg for local
imports via expected_duration_for_check() (new pure helper). The size +
mutagen-parse legs still run, so genuinely broken files are still caught — only
the release-vs-file duration comparison is skipped, and only for manual imports.
slskd downloads are completely unaffected.
This does NOT change the deeper matching (file still groups under Singles vs the
Parachutes album — the #767 canonical-version family); it stops the false
quarantine so the file imports.
Tests: 4 on the helper (local skips, download keeps, zero/None/garbage, string
coercion) + updated the routes context assertion. 557 import/integrity tests pass.
HiFi assembles FLAC from HLS segments and demuxes with `ffmpeg -c copy`,
which preserves total_samples=0 in the STREAMINFO of Tidal's fragmented/
streamed FLAC. Every audio frame is present and the file plays fine, but
mutagen computes length = total_samples / sample_rate = 0, so the integrity
check rejected it as 'zero-length audio' and quarantined nearly every HiFi
download. Users confirmed the quarantined files play normally once restored.
Length 0 is not proof of corruption at that point: the file already passed
the size gate, was identified as a real audio format, and has a valid info
block — a genuinely empty/truncated/stub file fails one of those earlier
checks instead. Treat length 0 as 'length unknown': accept the file and skip
the duration cross-check we can't perform without a length. mutagen never
decoded/validated frame data anyway, so this doesn't weaken real corruption
detection — size, parse, format, info-block, and duration-drift guards all
remain.
Tests: a large valid-parse length-0 file (streamed-FLAC signature) is now
accepted; a tiny length-0 stub still fails (size gate fires first).
Previously hardcoded at 3s (5s for tracks >10min) — files drifting
past that got quarantined with no user override. Live recordings,
alternate masterings, and some legitimate uploads routinely drift
further.
New setting `post_processing.duration_tolerance_seconds`. Default 0
means "use auto-scaled defaults" (unchanged behavior for users who
don't touch it). Positive value overrides the per-track defaults.
Capped at 60s — past that the check is effectively off.
Logic lifted to pure helper `resolve_duration_tolerance` in
file_integrity.py. Coerces every plausible input (None / empty /
zero / negative / unparseable / above-cap / numeric string / float)
to either a float override or None for auto. 12 tests pin every
shape.
Wired into `core/imports/pipeline.py` at the integrity-check call
site — runs for ALL matched downloads (Soulseek / Tidal / Qobuz /
HiFi / YouTube / Deezer-direct) since they all share that pipeline.
Settings UI input under Settings → Metadata → Post-Processing.
Discord report (fresh.dumbledore [VRN]): slskd sometimes ships broken files
(truncated transfers, corrupt FLAC, wrong file substituted on filename match).
They flowed through post-processing and only surfaced later — Plex/Jellyfin
scan failures, dead-air playback, duplicate detector tripping over the wrong
length. By that point the file was already tagged, copied, mirrored to the
media server, and recorded in provenance.
New module `core/imports/file_integrity.py`:
- `check_audio_integrity(path, expected_duration_ms=None) -> IntegrityResult`
- Three tiered checks, cheapest to most expensive:
1. File size sanity (catches 0-byte stubs and stub transfers)
2. Mutagen parse (catches header damage, wrong-format-with-right-extension)
3. Duration agreement vs. metadata source's expected length, ±3s tolerance
(5s for tracks over 10 minutes — long tracks naturally drift more)
- Returns IntegrityResult with `ok`, human-readable `reason`, and per-check
`checks` dict for debugging
- Never raises; pathological inputs return ok=False with explanation
Pipeline integration in `core/imports/pipeline.py:post_process_matched_download`:
- Hooks between the existing file-stability wait and AcoustID verification
- On failure: quarantine via existing `move_to_quarantine` helper, mark task
failed with descriptive error, clear matched-context, fire
`on_download_completed(success=False)` so the slot is released for retry
- Mirrors the existing AcoustID-failure path so retry behavior stays consistent
- Wrapped in try/except so an unexpected failure inside the check itself
cannot block downloads — logs and continues
This is intentionally tier 1: universal across formats, no external deps.
A future tier could verify FLAC STREAMINFO MD5 by decoding audio (needs
flac binary or libflac wrapper) — skipped for now since tier 1 catches the
dominant Discord-reported cases (truncated, 0-byte, wrong file).
Tests:
- `tests/imports/test_file_integrity.py` — 14 cases covering all three check
tiers, edge cases (zero/negative expected duration, long-track wider
tolerance, caller tolerance override), and the mutagen-unavailable
degradation path
- `tests/imports/test_import_pipeline.py` — two existing tests use 5-byte
fixture files that the new check would reject; they monkeypatch the
integrity check since they're testing plumbing (notification +
metadata_runtime forwarding), not integrity behavior
WHATS_NEW entry under '2.4.2' dev cycle.
