Lattice

MQTT Topic Topology

All canonical topics with producers/consumers in one map.

MQTT Topic Topology (v2026-08-02T101544Z-ab2bbdebf5) 2026-08-01 | All canonical topics with producers/consumers in one map. EventBus Initialization EventBus.__init__ _subscribers _filters _last_consume _overflow_counts event_bus_lvc.db CREATE TABLE IF NOT EXISTS lvc SELECT event FROM lvc ORDER BY ts ASC initializes in… Event Publishing EventBus.publish bus.publish() kv/events/{event_type} _lvc_queue.put_nowait(event) event_bus_lvc.db INSERT OR REPLACE INTO lvc (event_type, ts, event) VALUES (?, ?, ?) batch.append(ev2) publishes even… Event Subscription EventBus.subscribe subscribe() asyncio.Queue(maxsize=_SUBSCRIBER_MAX_DEPTH) SSE client GET /api/events GET /api/events?filter=holon:*,job:* registers subs… 1. Initialize EventBus 2. Load LVC from database 3. Start LVC writer thread 4. Subscribe to events 5. Publish event to MQTT… 6. Update LVC in database 7. Deliver event to match… Service Identity Payload { "service": "daemon", "version": "2026-05-23T074530Z-a3f8e2c", "role": "owner", "status": "starting", "environment": "d… Version Heartbeat Payload { "service": "daemon", "version": "2026-05-23T074530Z-a3f8e2c", "role": "owner", "status": "healthy", "uptime_seconds":… The NATS integration is optional and depends on the configuration. The LVC writer thread ensures that the last value cache is persisted to disk. Legend actor = initiates work · process = code path · store = state on disk · bus = durable queue · dashed = separate process cyan = request flow · pink = state read/write · dashed green = pull / return path · red = refusal

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This drawing is generated, not drawn. It is rebuilt from the source files below, so when they change the picture changes — a diagram here cannot quietly describe a system that no longer works this way.

Owner
Lattice
Slug
mqtt-bus-topology
Rendered
2026-08-02T101544Z
From commit
ab2bbdebf5
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3 paths
  • daemon/src/event_bus.py
  • daemon/config/services.yaml
  • daemon/docs/VERSIONING_BUS.md