Validate

Graph.validate() validates a building ontology against the Brick Schema, its default constraints (shapes) and user provided shapes. It does not modify the graph.

Please read `Shapes Constraint Language (SHACL)`_ to see how it is used to validate RDF graphs against a set of constraints.

Example

from brickschema import Graph

g = Graph(load_brick=True)
g.load_file('myBuilding.ttl')
valid, _, report = g.validate()
print(f"Graph is valid? {valid}")
if not valid:
  print(report)

# validating using externally-defined shapes
external = Graph()
external.load_file("other_shapes.ttl")
valid, _, report = g.validate(extra_graphs=[external])
print(f"Graph is valid? {valid}")
if not valid:
  print(report)

SHACL engines

Both validate() and compile() are backed by a pluggable SHACL engine, chosen with the engine keyword. When none is named, the first installed engine from this list is used:

• "shifty" (default) – Rust SHACL/SHACL-AF engine from pyshifty, installed by default. Runs rules to a fixed point.

• "topquadrant" – TopQuadrant’s Java implementation; install with pip install brickschema[topquadrant].

• "pyshacl" – pure-Python implementation, installed by default.

valid, _, report = g.validate(engine="pyshacl")

min_iterations and max_iterations bound how many rule passes are made. They apply to the pyshacl and topquadrant engines only, since shifty always runs to a fixed point.

Sample default shapes (in BrickShape.ttl)

# brick:hasLocation's object must be of brick:Location type
bsh:hasLocationRangeShape a sh:NodeShape ;
    sh:property [ sh:class brick:Location ;
        sh:message "Property hasLocation has object with incorrect type" ;
        sh:path brick:hasLocation ] ;
    sh:targetSubjectsOf brick:hasLocation .

# brick:isLocationOf's subject must be of brick:Location type
bsh:isLocationOfDomainShape a sh:NodeShape ;
    sh:class brick:Location ;
    sh:message "Property isLocationOf has subject with incorrect type" ;
    sh:targetSubjectsOf brick:isLocationOf .