Three follow-on fixes to the manual-search candidates modal once people
started actually using it:
1. NDJSON streaming. Manual search waited for every source to return
before showing anything. Now streams one event per source as each
completes — header line, source_results per source, done terminator.
Frontend appends rows incrementally via response.body.getReader().
2. Manual picks no longer auto-retry on failure. New _user_manual_pick
flag set on the task in /download-candidate. Both monitor retry
paths (not-in-live-transfers stuck + Errored state) bail on the
flag. Surfaces the failure to the user instead of silently picking
a different candidate via fresh search.
3. Non-Soulseek manual picks (youtube/tidal/qobuz/hifi/deezer/
soundcloud/lidarr) no longer stuck at "downloading 0%" forever. The
live_transfers IF branch now marks manual-pick tasks failed
directly when the engine reports Errored, instead of deferring to
the monitor (which bails on manual picks). Engine fallback in else
branch covers the rare race where the orchestrator's pre-populated
transfer lookup is missing the entry.
Plus a deadlock fix discovered along the way: the new failure path
synchronously called on_download_completed while holding tasks_lock,
which itself re-acquires the same Lock — non-reentrant
threading.Lock self-deadlocked the polling thread. While wedged, every
other endpoint that needed the lock (including /candidates → other
failed rows couldn't open modals) hung waiting. Moved completion
callbacks onto a daemon thread so the lock releases first.
Plus failed/not_found/cancelled rows are now ALWAYS clickable (not
just when the auto-search cached candidates) — the modal carries the
manual search bar, which is the user's recourse for empty results.
Plus manual download worker now runs on a dedicated thread instead of
competing with the batch's 3-worker missing_download_executor pool —
saturated batches no longer queue manual picks indefinitely.
All scoped to manual picks via the _user_manual_pick flag — auto
attempt flow byte-identical to before. Engine fallback gated on the
flag too so auto attempts in the else branch keep the original
do-nothing behavior (safety valve handles the stuck-forever case).
Also dropped _handle_failed_download from web_server.py — defined
but had no callers (dead code).
17 new unit tests pin the gate behavior:
- engine fallback: Errored/Cancelled/Succeeded/InProgress transitions,
manual-pick gate, terminal-state skip, soulseek skip, missing
download_id skip, engine returning None, orchestrator exception
- monitor: manual-pick skips not-in-live-transfers retry + Errored
retry
- IF-branch end-to-end: Errored marks failed, "Completed, Errored"
hits failure branch, auto attempts defer to monitor
Manual-search endpoint tests rewritten for NDJSON: 11 cases (validation,
single-source dispatch, parallel "all" dispatch, one-event-per-source
streaming shape, unconfigured-source skip + reject, header metadata,
per-source exception isolation).
Full suite 2259 passed, 1 skipped.
When an auto-download fails or returns "not found" with leftover
candidates, the user can already click the status cell to open a
modal showing those candidates and pick a different one. This adds
a manual search bar to that modal — type any query, hit search,
get a fresh round of results without having to bail out and start
over from the main search page.
Solves the case where the auto-query was bad (featured artist not
in title, parentheticals like "(Remastered 2019)" tripping the
matcher, slight artist-name variants, transliteration) but the
file genuinely exists on the source.
Frontend (downloads.js)
- Added a manual-search section above the existing auto-candidates
table inside the candidates modal.
- Source picker is smart per download mode:
- Single-source mode (soulseek-only / youtube-only / etc) shows
a "Searching X" label, no dropdown.
- Hybrid mode shows a dropdown with "All sources" default + every
configured source. Picking "All" runs parallel searches across
them and tags each result row with its source badge.
- Only configured sources show up; unconfigured are hidden.
- Validation: button disabled until query length >= 2, "Type at
least 2 characters" hint until threshold crosses.
- Loading state on search button while the request is in flight.
- Manual results render in a separate table above the existing
auto-candidates table, using the same row template (file /
quality / size / duration / user / ⬇ button) so the renderer
helper is shared.
- Click ⬇ reuses the existing `downloadCandidate(taskId, candidate,
trackName)` flow — same retry path, same AcoustID verification
when the file lands, no shortcut around the safety net.
- Re-running the search with a different query replaces the
previous manual results.
Backend (web_server.py)
- Extended `GET /api/downloads/task/<id>/candidates` response with:
- `download_mode` (e.g. 'hybrid', 'soulseek')
- `available_sources` (list of configured source IDs + labels)
- `source` field on each candidate (purely additive — frontend
auto-renderer ignores it on legacy code paths, manual-search
renderer uses it for the badge)
- Added `POST /api/downloads/task/<id>/manual-search`:
- Body: `{ query, source: 'all' | <source_id> }`
- Validates query length (>=2 trimmed) → 400
- Validates source against the configured-sources gate → 400
(rejects unconfigured sources even when explicitly named)
- For 'all': parallel `ThreadPoolExecutor` dispatch across every
configured download source, merged results
- For specific source: just that source
- Returns same shape as `/candidates` so the frontend renderer
is reused
- New module-level helpers: `_STREAMING_SOURCE_NAMES`,
`_infer_candidate_source`, `_serialize_candidate`,
`_list_available_download_sources`. The existing `/candidates`
endpoint also goes through `_serialize_candidate` so the source
badge is consistent across both flows.
Behavior preserved
- Existing modal layout / candidates table / ⬇ button are
byte-identical when the user doesn't use manual search.
- `downloadCandidate()` JS function untouched.
- `/candidates` and `/download-candidate` endpoints
backwards-compatible — only NEW fields added, nothing changed
or removed.
Tests
`tests/test_manual_search_endpoint.py` — 10 tests:
- `test_manual_search_validates_query_length`
- `test_manual_search_validates_source` (whitelist gate)
- `test_manual_search_handles_task_not_found` (404)
- `test_manual_search_dispatches_to_configured_source_only`
- `test_manual_search_all_dispatches_parallel`
- `test_manual_search_skips_unconfigured_sources`
- `test_manual_search_rejects_unconfigured_source_explicitly`
- `test_manual_search_returns_same_shape_as_candidates`
- `test_manual_search_single_source_mode_lists_source` (verifies
`available_sources` reflects the active mode)
- `test_manual_search_isolates_per_source_exceptions` (one source
throwing doesn't kill the merged result)
2242/2242 full suite green (was 2232 + 10 new). Ruff clean.
JS parses clean.
BoulderBadgeDad