Brick Validation Example (with BuildingMOTIF)

2025-02-04

We will use the Brick model from the previous post:

Expand for Brick Model

@prefix brick: <https://brickschema.org/schema/Brick#> .
@prefix rec: <http://w3id.org/rec/> .
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
@prefix owl: <http://www.w3.org/2002/07/owl#> .
@prefix unit: <http://qudt.org/vocab/unit/> .
@prefix : <urn:tutorial/> .

<urn:tutorial> a owl:Ontology ;
    owl:imports <https://brickschema.org/schema/1.4/Brick> ;
    owl:imports <http://qudt.org/2.1/vocab/unit> .

:building1 a rec:Building ;
    rdfs:label "Building 1" .

:floor1 a rec:Floor ;
    rdfs:label "Floor 1" .

:room1 a rec:Room ;
    rdfs:label "Room 1" ;
    rec:isPartOf :floor1 ;
    rec:isLocationOf :thermostat1 .

:thermostat1 a brick:Thermostat ;
    rdfs:label "Room 1 Thermostat" ;
    brick:hasPoint :room1-sp, :sensor1, :room1-occ .

:room1-sp a brick:Air_Temperature_Setpoint ;
    rdfs:label "Room 1 Setpoint" ;
    brick:hasUnit unit:DEG_F .

:sensor1 a brick:Air_Temperature_Sensor ;
    rdfs:label "Room 1 Temperature" ;
    brick:hasUnit unit:DEG_F .

:room1-occ a brick:Occupancy_Sensor ;
    rdfs:label "Room 1 Occupancy" .

We first set up the BuidlingMOTIF instance. The easiest thing to do here is create an in-memory instance so you can start fresh each time. Keep in mind that it can take a few seconds to load some of the larger ontologies, so for “real” projects you should consider using a persistent instance.

from buildingmotif import BuildingMOTIF

bm = BuildingMOTIF("sqlite://") # in-memory

Next, we load our model into BuildingMOTIF. Create a Model object, give it a name, and load the graph from the file.

from buildingmotif.dataclasses import Model

bldg = Model.from_file("tutorial.ttl")

Annoyingly, I haven’t yet gotten around to integrating the automatic handling of ontology dependencies like in the previous example. So, we need to manually load the Brick and QUDT ontologies into Library objects.

from buildingmotif.dataclasses import Library

brick = Library.load(ontology_graph="https://brickschema.org/schema/1.4/Brick")
qudt_unit = Library.load(ontology_graph="http://qudt.org/2.1/vocab/unit")

At this point, our Model and the two Library objects are stored in our (in-memory) BuildingMOTIF instance. We can now validate the model against the ontologies.

# the result is a ValidationContext object
context = bldg.validate([brick.get_shape_collection(), qudt_unit.get_shape_collection()])

The ValidationContext object contains the results of the validation. It can also interpret the raw validation results into a more human-readable format.

Specifically, ValidationContext has the following attributes:

report_string: a formatted version of the SHACL validation report
report: the raw SHACL validation report as an rdflib Graph object
valid: a boolean indicating whether the model is valid
get_broken_entities(): lists all entities which failed validation
get_diffs_for_entity(entity): lists all reasons why a specific entity failed validation
diffset: a set of human-readable reasons why the model is invalid
- this interprets the raw SHACL results into a more human-readable format

Complete Demo

# /// script
# requires-python = "==3.10"
# dependencies = [
#   "buildingmotif @ https://github.com/NREL/BuildingMOTIF.git#develop",
# ]
# ///
from buildingmotif import BuildingMOTIF
from buildingmotif.dataclasses import Model
from buildingmotif.dataclasses import Library

bm = BuildingMOTIF("sqlite://") # in-memory

# load ontologies
brick = Library.load(ontology_graph="https://brickschema.org/schema/1.4/Brick")
qudt_unit = Library.load(ontology_graph="http://qudt.org/2.1/vocab/unit")

# create model
bldg = Model.from_file("tutorial.ttl")

# validate the model (includes running SHACL inference)
context = bldg.validate([brick.get_shape_collection(), qudt_unit.get_shape_collection()])

print(context.report_string)
print(f"Is valid: {context.valid}")

You can run this script using the uv tool. Simply copy the script into a file called validate.py and run uv run validate.py. This uses a very cool uv script feature to automatically install the dependencies and run the script.