Cold start fetched all logs in one bulk query then processed them in a tight
synchronous loop with no yields, blocking the asyncio event loop for seconds
on datasets of 30K+ rows. This stalled every concurrent await — including the
SSE stream generator's initial DB calls — causing the dashboard to show
INITIALIZING SENSORS indefinitely.
Changes:
- Drop _cold_start() and get_all_logs_raw(); uninitialized state now runs the
same cursor loop as incremental, starting from last_log_id=0
- Yield to the event loop after every _BATCH_SIZE rows (asyncio.sleep(0))
- Add SSE keepalive comment as first yield so the connection flushes before
any DB work begins
- Add Cache-Control/X-Accel-Buffering headers to StreamingResponse
23 tests verifying that each background worker degrades gracefully
when its dependencies are unavailable, and that failures don't cascade:
- Collector: Docker unavailable, no state file, empty fleet
- Ingester: missing log file, unset env var, malformed JSON, fatal DB
- Attacker: DB errors, empty database
- Sniffer: missing interface, no state, scapy crash, non-decky traffic
- API lifespan: all workers failing, DB init failure, sniffer import fail
- Cascade: collector→ingester, ingester→attacker, sniffer→collector, DB→sniffer
