Build an ontology package¶

Create a small package that states Dog is a subclass of Animal, then write it as JSON. This tutorial requires Python 3.11 or later.

Install¶

pip install ontophora

Create the entity records¶

Save the following as animals.py:

from ontophora import Klass, SubClassOf, records_to_json

animal = Klass(uid="0x1", iri="https://example.org/animals#Animal")
dog = Klass(uid="0x2", iri="https://example.org/animals#Dog")

dog_is_an_animal = SubClassOf(
    uid="0x3",
    sub_class_expression=dog.uid,
    super_class_expression=animal.uid,
)

print(records_to_json([animal, dog, dog_is_an_animal]))

Each model supplies its own kind; you provide only the fields that identify or connect the construct. Reference fields accept a bare UID and retain it as a validated reference value.

Run it¶

python animals.py

The program prints one JSON array. Its records use an envelope that separates each record UID from its construct payload:

[
  {"uid": "0x1", "construct": {"kind": "Class", "iri": "https://example.org/animals#Animal"}},
  {"uid": "0x2", "construct": {"kind": "Class", "iri": "https://example.org/animals#Dog"}},
  {"uid": "0x3", "construct": {"kind": "SubClassOf", "sub_class_expression": {"uid": "0x2"}, "super_class_expression": {"uid": "0x1"}, "axiom_annotations": []}}
]

Read the package back¶

Replace the final print with this code:

from ontophora import records_from_json

text = records_to_json([animal, dog, dog_is_an_animal])
records = records_from_json(text)

assert records[2].kind == "SubClassOf"
assert str(records[2].sub_class_expression) == "0x2"

Ontophora validates each payload using kind to select its concrete model. Next, learn how to read and write JSON at an application boundary.