Replaces the POC single-threshold check with a real per-rule engine over
the live monitor feed.
- AlertRule / AlertEvent tables (auto-created via create_all; no migration).
Rule = {metric, comparison, threshold_db, duration_s, clear_margin_db,
schedule, channels, recipients}.
- alerts.py: per-(unit,rule) state machine IDLE->ACTIVE->IDLE with duration
debounce (both edges) + clear_margin hysteresis; onset/clear are distinct
events; optional nighttime schedule; rule cache w/ invalidation. The
state-machine core (_evaluate_step) is pure (no DB/clock) for testing.
- Dispatch is a server log (POC); _dispatch() is the seam for a Terra-View
webhook (email/SMS) later.
- CRUD: POST/GET/PUT/DELETE /{unit}/alerts/rules, GET /{unit}/alerts/events,
POST /{unit}/alerts/events/{id}/ack.
- test_alert_evaluator.py: synthetic level series proves onset debounce,
spike rejection, hysteresis hold, and below-comparison (4/4 pass, no device).
Source-agnostic: the same rules transfer unchanged if a unit's feed is later
sourced from FTP intervals instead of the DOD monitor.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
The piece the live-view + alerting work was building toward.
monitor.py — one DOD poll loop per device, broadcast to many subscribers:
- browser WebSockets (fixes the single-connection "second viewer sees
nothing" contention — browsers no longer each open a device stream)
- the alert evaluator (can keep a feed running with no browser via
/monitor/start, so alerting runs continuously)
- persistence (each snapshot written like the poller)
DOD-sourced, so the broadcast carries ln1/ln2 (which DRD cannot). All polls
go through the existing per-device lock + pool, so it serializes safely with
the background poller and on-demand commands.
alerts.py — pluggable POC evaluator: fires (logs) when ALERT_METRIC exceeds
ALERT_THRESHOLD_DB with an ALERT_COOLDOWN_SECONDS cooldown. The rule
(instantaneous vs sustained vs L10) is the single swap point; dispatch is a
server log for now (email/SMS later).
Endpoints:
- WS /api/nl43/{unit_id}/monitor subscribe to the shared feed
- POST /api/nl43/{unit_id}/monitor/start keep feed alive w/o a browser
- POST /api/nl43/{unit_id}/monitor/stop drop the keep-alive
- GET /api/nl43/_monitor/status running/subscribers/keepalive
WS endpoint races queue.get() against a disconnect watcher so an idle feed
still detects client drop and doesn't leak a subscription.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
serversdown