On a vehicle entry, two paths captured the SAME Hikvision camera within ~1s —
the ANPR bridge (barrier-driving) and the advisory snapshotAsync (evidence/
telemetry) — each from a separate adapter instance. Hikvision serves snapshots
single-threaded, so the second concurrent GET returned HTTP 503; the bridge
then fail-softed and burned its 12s debounce, producing a ~74s "slow" subscriber
entry (observed 2026-06-25, Qazim Mulleti / AB816NN — plate read was instant at
conf 1.000; the delay was the 503/debounce churn, not recognition).
Add captureSnapshotShared() in snapshot.ts: a module-level, deviceId-keyed cache
that both paths call. It coalesces in-flight captures (the 2nd caller awaits the
1st's pull → no concurrent 503), serves a brief freshness window (1500ms) so the
bridge→advisory sequence for one vehicle reuses one frame, never caches a failure
(next caller retries), and keys by deviceId (no cross-camera/stale-vehicle reuse).
Wired into anpr-entry.ts (bridge) and snapshot.ts (advisory).
Tests: snapshot.test.ts (concurrent coalescing, TTL reuse, TTL-lapse re-pull,
failure-not-cached, per-camera keying); anpr-entry.test.ts mock updated. 168
server tests green.
NOTE: this removes the latency (the 503 collision). The separate double-entry
(two signed vehicle_entry for one car) — debounce-too-short / stamp-before-
success — is still open; less likely now but not eliminated.
Claude-Session: https://claude.ai/code/session_01Xcm6ikLgGoCxxHrxtjkk5V
Wire the lane camera's vehicle event into the gated subscription flow: on a
vehicle/active push from an opt-in (config.anpr) camera, AnprBridge pulls a fresh
snapshot, runs ANPR, applies a stricter entry confidence floor, debounces, and —
matching the plate to a subscription BEFORE emitting — emits a kind:"plate" read.
The existing ReadDispatcher -> SubscriptionFlow then signs the entry/exit and opens
the barrier. A plate is never the sole authority: it routes through the same gate
(active/window/blocklist/car-count) as any credential. Fail-soft, fire-and-forget,
subscriber-only by construction. Field-verified end to end (plate AA504LX opened the
entry barrier and appended a signed vehicle_entry).
Add an admin master switch (site_config.anpr_entry_enabled, default ON) in Site
Settings that disables ONLY the barrier-driving bridge; advisory snapshot-ANPR and
lane busy/free are unaffected. Read live per event, so toggling takes effect with no
restart. Migration 0013 (additive ALTER ADD COLUMN, default 1).
- New: apps/server/src/anpr-entry.ts (AnprBridge) + tests (9)
- hikvision-alarm.ts hands vehicle detections to the bridge (fire-and-forget) + wiring tests (3)
- server.ts reorders the read flows above the hik-alarm registration
- snapshot.ts exports buildCamera for reuse
- env: VISION_ENTRY_MIN_CONFIDENCE (0.85), ANPR_DEBOUNCE_MS (12000)
- site route + SiteSettings checkbox + i18n (sq/en parity)
- wiki: lane-presence-and-anpr-entry / lpr-camera / index / log -> BUILT
Claude-Session: https://claude.ai/code/session_01Xcm6ikLgGoCxxHrxtjkk5V
julian