BACnet, RDF, and BRICK

Open-FDD treats the building as a knowledge graph: sites, equipment, and points (and BACnet topology) live in a single semantic model. CRUD and POST /bacnet/point_discovery_to_graph update this model; SPARQL queries it.

Roles

Layer Responsibility
diy-bacnet-server BACnet RPCs: Who-Is, point discovery (returns JSON objects per device). Open-FDD calls these.
Open-FDD Calls point discovery, builds clean BACnet TTL from the JSON, merges into the in-memory graph (Brick from DB + BACnet). CRUD owns sites, equipment, points. SPARQL runs over the combined model; sync writes config/data_model.ttl.

Flow

  1. Point discovery — Open-FDD calls POST /bacnet/point_discovery (gateway RPC) for a device instance; gateway returns a list of objects (object_identifier, object_name, etc.).
  2. Point discovery to graph — POST /bacnet/point_discovery_to_graph (same instance, update_graph: true) turns that JSON into clean BACnet TTL and updates the in-memory graph; optionally writes config/data_model.ttl. SPARQL and GET /data-model/ttl see Brick + BACnet.
  3. Points in DB — Create or edit points via CRUD (set bacnet_device_id, object_identifier, object_name). Optionally GET /data-model/export then LLM or human adds Brick types then PUT /data-model/import.
  4. Scrape — Data-model driven (points with bacnet_device_id / object_identifier).

Try it (Open-FDD Swagger)

1. Who-Is

  • Open http://localhost:8000/docs. Find POST /bacnet/whois_range. Body: {"request": {"start_instance": 1, "end_instance": 3456800}}. Execute; note a device instance (e.g. 3456789).

2. Point discovery to graph

  • Find POST /bacnet/point_discovery_to_graph. Body: {"instance": {"device_instance": 3456789}, "update_graph": true, "write_file": true}. Execute. Open-FDD calls the gateway, gets point discovery JSON, builds BACnet TTL, and updates the in-memory graph and file.

3. Check

  • GET /data-model/ttl or POST /data-model/sparql (e.g. SELECT ?dev WHERE { ?dev a bacnet:Device }).

Summary

  • Building as knowledge graph: one semantic model (BRICK + BACnet), updated by CRUD and by point_discovery_to_graph.
  • BACnet in the graph is produced by Open-FDD from point discovery JSON (clean TTL); SPARQL validates and queries the combined model.