User caught downloading Kendrick Mr. Morale: three tracks (Rich
Interlude, Savior Interlude, Savior) showed ✅ Completed in the modal
but were missing on disk. Log forensics revealed two layered bugs.
Bug 1 — Verification wrapper assumed success on quarantined files
(`core/imports/pipeline.py`):
The outer `post_process_matched_download_with_verification` had a
fallback at the "no `_final_processed_path` in context" branch that
marked the task completed and notified `success=True`. The inner
post-processor sets `_final_processed_path` only when the file
actually reaches its destination. Integrity-rejected files
(`_integrity_failure_msg` set) and race-guard-failed files
(`_race_guard_failed` set) get quarantined or skipped without ever
setting `_final_processed_path`, so they fell straight into the
"assume success" branch.
Confirmed in user's log:
No _final_processed_path in context for task d5b88b84-... —
cannot verify, assuming success
That line fired for the same task right after the integrity check
quarantined the source file. Result: ✅ Completed in UI, file in
quarantine, never delivered.
Fix: explicit checks for `_integrity_failure_msg` and
`_race_guard_failed` markers BEFORE the assume-success fallback.
Either marker set → task status='failed' with descriptive
error_message + `_notify_download_completed(success=False)`. The
pre-existing assume-success behavior preserved when no failure
markers are set (some legitimate flows complete without setting
`_final_processed_path`).
Bug 2 — AcoustID skip-logic too lenient
(`core/acoustid_verification.py`):
The "language/script" exemption was:
if best_score >= 0.95 and (title_sim >= 0.55 or
artist_sim >= ARTIST_MATCH_THRESHOLD):
The OR-clause fired for English-vs-English titles by the same artist
that share NO actual content. Confirmed in user's log: requested
"Rich (Interlude)" by Kendrick Lamar, AcoustID identified the audio
as "R.O.T.C. (interlude)" by Kendrick Lamar (a totally different
song from his 2010 mixtape) — same artist scored ≥ARTIST threshold,
shared word "interlude" pushed title_sim above 0.55, skip fired.
Verification returned SKIP instead of FAIL, the wrong file was
accepted as the answer for three different track requests.
Fix: skip now requires positive evidence the mismatch is a real
language/script case:
(a) Non-ASCII chars present in either title AND artist matches strongly
→ real transliteration case (kanji ↔ romaji etc)
(b) BOTH title_sim >= 0.80 AND artist_sim >= ARTIST threshold
→ minor punctuation/casing differences
English-vs-English with very different titles by the same artist no
longer skipped — verification correctly returns FAIL, the wrong file
gets quarantined, the new wrapper logic above marks the task failed.
Tests:
- `tests/test_integrity_failure_marks_task_failed.py` — 4 cases
pinning the wrapper-level state machine: integrity marker → failed,
race-guard marker → failed, no markers → still assumes success
(legacy path preserved), integrity-failure-takes-priority over
missing-final-path fallback.
- `tests/test_acoustid_skip_logic.py` — 7 cases pinning the skip
exemption: user's R.O.T.C-vs-Rich case → FAIL (regression test),
Savior-vs-R.O.T.C → FAIL (same bug surface), Japanese kanji →
romaji → SKIP (real language case still works), MAAD vs M.A.A.D →
PASS or SKIP (punctuation tolerance), low fingerprint score →
never skipped, high score but artist mismatch → no longer skipped,
Crown vs Crown of Thorns → no longer skipped.
Verified: full suite 1793 pass (11 new), ruff clean.
WHATS_NEW entry under '2.4.2' dev cycle.
User reported searching "Maduk - Leave A Light On" on Tidal silently
downloaded Tom Walker's completely different song of the same name, then
embedded Maduk's metadata into Tom Walker's audio. Three layers of
defense all failed permissively. Two of them are fixed here; the third
(score formula weights) was left alone since these two together cover it.
Layer 1 fix — candidate artist gate (web_server.py:27782)
Old: `if _best_artist < 0.4 and confidence < 0.85: continue`
New: `if _best_artist < 0.5 and confidence < 0.85: continue`
SequenceMatcher returns exactly 0.400 for "maduk" vs "tom walker"
(5-char vs 10-char strings with coincidental char matches), which
slipped past the strict `< 0.4` check. The word-boundary containment
check earlier in the function already short-circuits legitimate
formatting variations to sim=1.0, so falling to SequenceMatcher means
strings are genuinely different. 0.5 closes the fencepost AND gives
a small safety buffer.
Layer 3 fix — AcoustID verification (acoustid_verification.py:316)
When title matches but artist doesn't AND expected artist isn't found
anywhere in AcoustID's returned recordings:
Old: always SKIP (let file through, assume cover/collab)
New: FAIL if artist_sim < 0.3 (clear mismatch)
SKIP if artist_sim >= 0.3 (ambiguous — cover/collab/formatting)
The 0.3 cutoff catches hard mismatches like Maduk/Tom Walker (sim ~0.2)
while preserving benefit-of-the-doubt for borderline artist formatting
differences. Legitimate covers and collabs where the expected artist
appears anywhere in AcoustID's recordings still PASS via the existing
secondary-match loop above.
Both fixes are defense-in-depth — either alone would have caught this
bug. Together they close the pre-download AND post-download gaps.
All 292 tests pass. Version bumped to 2.39 with changelog entries.
The high-confidence fingerprint skip (≥0.95) assumed title mismatches
were language/script differences and bypassed verification. But a high
fingerprint score just means AcoustID identified the audio confidently —
not that it matches the requested track. Now requires partial title
(≥0.55) or artist (≥0.60) similarity before skipping, so completely
wrong files (e.g. different song/artist from same remix producer) are
correctly rejected.
When the fingerprint score is >=0.95 but title/artist don't match
(e.g. English expected vs Japanese returned), SKIP instead of FAIL.
A 95%+ fingerprint means the audio IS the correct recording — the
metadata mismatch is just a language/script difference, not a wrong
file. Prevents Japanese, Chinese, Korean, and other non-Latin tracks
from being falsely quarantined.
Happy path unchanged — matching title/artist still returns PASS at
the earlier check before this code is reached.
AcoustID sometimes returns featuring info in square brackets like [W/ Barnes Blvd.] instead of parentheses. The normalizer only stripped parenthetical featuring tags, so these tracks failed verification and got quarantined despite being correct. Now strips [W/ ...], [with ...], [feat. ...], and [ft. ...] bracket patterns too.
Expand track title normalization and refine album grouping logic.
- core/acoustid_verification.py: Broadened the parenthetical-suffix regex to strip year-based remasters and additional variants (e.g. "2025 Remaster", "single edit", "album edit") while still removing common extras like (Live), (Deluxe), (Radio Edit), and featuring tags.
- web_server.py: Restrict the smart album grouping to only run for singles/auto-detected albums; explicit album downloads now preserve the original Spotify album name to avoid mangling names (e.g. reworked/remastered vs deluxe). Added explicit logging for both smart grouping and skipped grouping paths. The verification post-processing worker now checks an is_album_download flag in context and skips re-grouping when true, with fallback logging on errors.
These changes prevent unintended renaming of explicit album downloads and improve normalization of common title suffixes.
Add optional post-download audio fingerprint verification using AcoustID.
Downloads are verified against expected track/artist using fuzzy string
matching on AcoustID results. Mismatched files are quarantined and
automatically added to the wishlist for retry.
- AcoustID verification with title/artist fuzzy matching (not MBID comparison)
- Quarantine system with JSON metadata sidecars for failed verifications
- fpcalc binary auto-download for Windows, macOS (universal), and Linux
- MusicBrainz enrichment worker with live status UI and track badges
- Settings page AcoustID section with real-fingerprint connection test
- Source reuse for album downloads to keep tracks from same Soulseek user
- Enhanced search queries for better track matching
- Bug fixes: wishlist tracking, album splitting, regex & handling, log rotation
Broque Thomas
Antti Kettunen
Broque Thomas