The debug block exposed only gauges (buckets, quarantined, inFlight) — state, not work.
A real flapping Firestick reads as flap.buckets:36, quarantined:0, indistinguishable
from healthy. Add lightweight in-memory throughput counters (total + last-completed
rolling window) so the server tells the flapper/flood story itself.
- lib/rolling-counter.js: shared bounded scalar counter (total, curWindow, lastWindow,
windowStart); rolls lazily on bump AND read (no timer), idle decays to 0.
DEBUG_STATS_WINDOW_MS default 60000.
- flap-limiter: refused{Total,LastWindow} (every allow:false), quarantineStarts{Total,
LastWindow} (a quarantine event stays visible after the gauge decays).
- ota-breaker: stats() rateBackoff{Total,LastWindow}.
- ota-download-guard: servedTotal/shedTotal alongside the per-window values.
- database: maintenance sweepsTotal (confirm the prune is firing, not stalled).
- routes/status: debug block gains ota_breaker + the new fields (aggregate-only, cheap).
Tests: rolling-counter window-roll + idle decay; each counter increments on the right
event; booted /api/status asserts the new fields present + numeric. Suite 285/285.
Fallout doc: observability section lists the fields + what each tells a soak-watcher.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Expose the new internal states so we can SEE the limiters biting during the alpha soak
instead of grepping logs. /api/status now carries debug: {
flap: {buckets, quarantined},
ota_download: {inFlight, servedThisWindow, shedThisWindow, windowCount},
maintenance: {deleted, ms, at, running}, // last status-log prune
log_coalescer_buffer,
}. Aggregate counts only (no device ids/secrets), cheap in-memory reads. stats()
added to flap-limiter + ota-download-guard (singleton prod state), getMaintenanceStats
from database. Asserted in the booted /api/status test.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Every new subsystem is disable-able via env (flip + restart, no redeploy/bisect):
- FLAP_LIMITER_ENABLED=false -> flap limiter always allows.
- OTA_DOWNLOAD_GUARD_ENABLED=false -> download guard always admits.
- MAINTENANCE_BAND_GATE_ENABLED=false -> interval maintenance ignores band.
- CONNECT_RATE_QUARANTINE_TRIPS=0 -> quarantine off (already; confirmed).
Startup prune is never band-gated regardless. Kill switches table added to the fallout
doc. Tests assert each OFF behaviour.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
The flap limiter's auto-quarantine used to run `UPDATE devices SET blocked = 1` — a
PERMANENT, human-cleared block on an automatic trigger. A stuck-then-recovered device
stayed dark until someone noticed.
- Removed the auto-write from ws/deviceSocket.js. devices.blocked is now written ONLY by
an operator (dashboard endpoint / direct SQLite).
- Quarantine moved into lib/flap-limiter.js as IN-MEMORY, TIME-LIMITED state: after
connectRateQuarantineTrips trips in a window the identity is quarantinedUntil = now +
connectRateQuarantineMs (new, default 30m); check() then refuses cheaply with
reason:'quarantined' and AUTO-CLEARS when the window passes. Safe in-memory now that
Item A ended the restart loop, and a self-healing auto-action must not survive as a DB row.
- Log quarantine START once; repeat refusals go through the coalescer. Stale
"-> blocked=1" comments updated.
- connectRateQuarantineTrips=0 still disables it.
Tests: quarantine engages after N trips, refuses cheaply during the window, auto-clears
after connectRateQuarantineMs; and an integration flapper is quarantined while
devices.blocked stays 0.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
The #142 burst throttle (5/10s) misses a device flapping every 3-5s (~2-3/10s) — yet
each cycle is an expensive register+build+acks and one status_log row (the spiral
trigger). Now that Item A ends the restart loop that used to wipe in-memory throttle
state every ~40s, an in-memory sustained limiter can finally bite.
- lib/device-identity.js: SNAT-safe identity resolution — device_id -> fingerprint
(map via device_fingerprints -> device_id, else raw fp) -> device_token -> ONE bounded
global anon bucket. NEVER IP (the fleet SNATs to 10.10.10.1). An unidentifiable client
is still bucketed (collectively) so an anon flood is capped, never unthrottled.
- lib/flap-limiter.js: per-identity connect-frequency over a long window
(CONNECT_RATE_WINDOW_MS=5min, CONNECT_RATE_MAX=20; anon bucket cap 60). Over the rate
-> refuse + disconnect (cheap). Bounded by an idle sweep (anon bucket never swept).
Optional auto-quarantine: a device_id-resolved hard flapper -> blocked=1.
- Wired at the device:register gate BEFORE fingerprint tracking/throttle/DB/build,
skipping same-socket playlist refreshes. Sweep started in server.js.
Tests: 4s-flapper refused after the window max; 60s-normal never; two device_ids
independent (never IP); device_id-less bucketed by fingerprint; neither id nor
fingerprint capped via global anon; idle sweep preserves the anon bucket. Suite 254/254.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
