Claim jobs atomically [CRIT-01]
- Replace JobService.read_next_queued_job with claim_next_queued_job, which
selects and transitions QUEUED -> PROCESSING inside one transaction. The old
read-then-write sequence left a window in which two workers could observe the
same QUEUED row.
- Add the missing .limit(1). The poll previously ordered the entire queued set
and discarded all but the first row.
- Drop the eager loads from the hot poll entirely. They were pure waste:
process_queued_job immediately re-reads the job through read_job with the
relationships it actually needs.
- Guard the row with with_for_update(skip_locked=True) on PostgreSQL so the
claim stays correct once more than one worker exists. On SQLite the claim is a
bounded single-writer transaction.
- Correct the comment at the remaining direct-call claim site, which described
the hazard rather than the guarantee.
Reuse the provider connection [HIGH-02]
- Build the ServiceBundle once per worker loop instead of once per job, and
close it at loop shutdown. Every job previously constructed a new
SourceService, and with it a new provider adapter and a new httpx.AsyncClient,
paying a full TLS handshake per page and discarding the connection pool.
- process_next_queued_job now accepts an optional caller-owned bundle and only
closes bundles it created itself.
Uncap the provider timeout [HIGH-03]
- Remove le=20.0 from worker_provider_timeout_seconds. The cap equalled the
default, so the ceiling could never be raised, and dense-page vision
transcription routinely needs longer. Default raised to 180s.
- Pass an explicit httpx.Timeout to the OpenRouter AsyncClient. httpx defaults
every phase to 5 seconds, so the real read budget was 5s regardless of the
configured value; the outer asyncio.wait_for could never be the binding
constraint. Connect stays at 10s.
Tighten the provider boundary [MED-03]
- Declare model, current_request_manifest, current_transport_evidence, and
aclose on the TranscriptionProvider Protocol.
- Delete the per-call inspect.signature(adapter.transcribe).parameters
reflection and the untyped kwargs dict it fed. The Protocol had declared
requested_model all along, so the reflection was dead defensive weight on the
hot path.
- Replace the three getattr probes for aclose and the evidence attributes with
direct typed access.
Deduplicate bundle construction [MED-06]
- Add ServiceBundle.from_session_factory and ServiceBundle.aclose, replacing the
duplicated four-service instantiation blocks in app.py and worker.py.
- _recover_stale_processing_jobs now uses the bundle built moments earlier
instead of constructing a second JobService.
Tests
- Claiming returns the oldest job, marks it PROCESSING, never hands the same job
out twice, and emits exactly one unadorned SELECT carrying LIMIT and no JOIN.
- The worker loop threads one bundle through consecutive jobs and closes it once
at shutdown; a caller-owned bundle is left open.
- Settings accepts a timeout above 20 seconds and still rejects zero.
- The OpenRouter client's read, write, and pool timeouts track the configured
budget rather than the httpx default.
Note: .env in this checkout still pins WORKER_PROVIDER_TIMEOUT_SECONDS=20 and
should be raised to pick up this fix.
Verified: 268 passed, 4 skipped; ruff check clean.
Co-authored-by: Copilot App <[email protected]>
Jim Lancaster
