Plan #693. Large-catalog backfill (Anduo) no longer sprints to the timeout
wall and dies as an error each run. Builds on the cursor checkpoint (#689).
- Time-boxed chunks: BACKFILL_TIMEOUT_SECONDS(1170)→BACKFILL_CHUNK_SECONDS(600),
far under the 1350 soft limit. Hitting it = normal chunk boundary (the
TimeoutExpired path already captures partial output + the cursor), not a
near-wall death.
- Run-until-done state machine driven by config_overrides[_backfill_state]
(running/complete/stalled). A running backfill auto-continues in chunks
across ticks until gallery-dl exits cleanly (rc=0 = reached the bottom →
'complete'); a safety-cap (BACKFILL_MAX_CHUNKS=200) + the #689 stall-guard
pause a pathological walk as 'stalled'. Replaces the N-runs counter
(backfill_runs_remaining repurposed as the cap countdown).
- Progress, not error: a chunk that timed out but advanced (cursor moved
and/or files written) is reclassified TIMEOUT→PARTIAL (status 'ok').
- Retry storm tamed: gallery-dl retries 3→2, downloader timeout 120→60s, so
one stuck CDN file fails in ~1-2 min not ~10 (Anduo #40838).
- API: POST /sources/{id}/backfill now takes {action: start|stop}; service
start_backfill/stop_backfill; new enabled sources auto-arm run-until-done;
source dict exposes backfill_state + backfill_chunks.
Frontend (Start/Stop control + state badge) lands in the next push.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Routine subscription polls walked the entire post history every tick
even when nothing had changed, because gallery-dl's default `skip: True`
continues iterating archived posts. A creator with ~550 archived posts
(Knuxy patreon) saturates the 870s wall-clock cap before completing,
even with zero downloads needed. Plus, a tier-limited run that
downloaded hundreds of files but ran out the clock should be a
warning, not an error.
Two coupled changes, both operator-flagged 2026-06-01:
* **Tick mode (default, cron polls).** New `TICK_SKIP_VALUE = "exit:20"`
asks gallery-dl to exit after 20 contiguous archived items. Fresh
subscriptions + new-content cases still walk normally; established
subscription with zero new content exits in ~30s of HEAD requests
instead of pegging the timeout. 20 (not 5) gives headroom against
paywall warnings interleaving with archived items.
* **Backfill mode (explicit, operator-triggered).** Sticky for N runs
via new `Source.backfill_runs_remaining` (alembic 0031). While > 0,
downloads use `skip: True` + 1800s timeout. Auto-decrements per run
with early-reset to 0 when a clean run finds zero files (queue
drained). N defaults to 3 — multiple runs give the system enough
budget to finish a deep walk across timeout boundaries. New
`POST /api/sources/{id}/backfill` arms the source; "Deep scan"
button on each SourceRow (chip shows remaining count) wires it.
Plus partial-success classifier: non-zero gallery-dl exit + ≥1 file
downloaded + no source-level error fires `ErrorType.PARTIAL`, which
download_service maps to `status=\"ok\"`. The run did real work; the
next tick continues via gallery-dl's archive. No more red events for
"timed out mid-walk after downloading 300 files."
Retires `SourceConfig.skip_existing` — skip value is now derived from
the source state and passed as a separate `skip_value` parameter
through download() / _build_config_for_source(). `GD_DEFAULTS` drops
the now-dead key (was inert data after this refactor).
Tests cover:
* tick + backfill skip-value emission in _build_config_for_source
* PARTIAL classifier branch + TIER_LIMITED-wins-over-PARTIAL ordering
* SourceService.set_backfill_runs validation + persistence
* /api/sources/{id}/backfill 200/400/404 paths
* download_service auto-decrement / auto-reset / tick-mode-no-touch
* PARTIAL → status=ok in the orchestrator (no consecutive_failures bump)
Today's platform-cooldown commit (61ce1ce) only filtered the scan tick
— manual /api/sources/<id>/check still bypassed it. Operator-flagged
2026-05-30: clicked "Retry failed" on a Patreon failure pile and saw
every one go 'queued' without realising the cooldown wasn't in the
loop. Bulk retry with N sources on a cooled-down platform bowls right
back into the rate limit the cooldown is trying to prevent.
**Backend (`/api/sources/<id>/check`):**
- Reads optional `?force=true` query flag.
- Without force: queries `active_platform_cooldowns` (renamed from the
private `_platforms_in_cooldown` since it's now a cross-module API).
If the source's platform is in cooldown, returns **202** with
`{status: 'deferred', platform, cooldown_until}` — no event created,
no dispatch.
- With force: cooldown skipped entirely.
- In-flight guard always applies (no point creating duplicate pendings).
**Frontend (`sourcesStore.checkNow(id, {force=false})`):** new optional
`force` flag → adds `?force=true` to the URL.
**Frontend (`DownloadsTab`):**
- `onRetrySource` (single-source RETRY click): passes `force: true` →
explicit operator override, useful for rapid auth-fix testing.
- `onRetryAll` (RETRY ALL + MaintenanceMenu "Retry failed"): no force →
cooldown respected. Tallies `deferred` alongside `queued` /
`already_running`; toast reads e.g. *"5 queued, 12 deferred
(cooldown), 3 already running"*. That count is the operator's
diagnostic answer for "is rate-limit the cause of most failures?"
(12-of-20 deferred → yes; 0 deferred → no).
**Auto-resume:** no new sweep needed. Deferred sources still have stale
`last_checked_at`, so the next scan tick after the cooldown AppSetting
expires picks them up via `select_due_sources` (which already filters
on `active_platform_cooldowns`).
Tests: two new — deferred-on-cooldown returns 202 with the right body
and no dispatch; force=true overrides the cooldown and creates the
event normally.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
8 blueprints each defined an identical _bad() (two variants: with/without
detail). Extracted error_response() into api/_responses.py; each blueprint
now imports it `as _bad` so call sites are unchanged. The detail-aware
canonical subsumes both variants. Left settings.py's distinct _bad_int and
the inline jsonify error sites (not duplicated helpers).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
D1 scheduler visibility: AppSetting last-tick stamp on every Beat tick +
GET /api/sources/schedule-status (last_tick_at/next_due_at/due_now/auto_sources)
+ SchedulerStatusBar on the Subscriptions tab (re-polled every 30s).
D2 failing-source rollup: ?failing=true on the sources list + FailingSourcesCard
on Downloads with per-source and bulk "retry" (re-runs the feed via /check).
D3 activity sparkline: GET /api/downloads/activity hourly buckets + CSS bar
chart by the stat chips (failures stacked in error color); refreshes on live poll.
D4 credential staleness: surface last_verified age + "re-verify recommended"
warning past 30d; also fixes the dead last_verified_at field-name mismatch so
the verification row renders at all.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
bvandeusen