SHACL shapes

The closed-world contract over the open-world OWL class graph. OWL says what can be inferred; SHACL says what a conforming document must carry. This page indexes the 408 node shapes natively, explains the regulatory-weight severity scheme, the 365 domain/range-as-constraint shapes, and the asserted-vs-entailed / SHACL-AF boundary. Every count is read at build time from the committed shapes TTLs (source/03-standards/ontology/opda-*-shapes.ttl), so it cannot drift from the model. The term-by-term reference — the only one that resolves the blank nodes — is the embedded SHACL Play! rendering.

1 · Node-shape inventory

The shapes graph is one cross-cutting file (opda-shapes.ttl) plus a small resource-shape set per module. opda-shapes.ttl carries the per-leaf Category-1/2 constraint shapes and the cross-cutting SHACL-AF rules; the module shape files carry the per-Kind resource shapes that compose with the overlay profiles. Shapes target classes via sh:targetClass / sh:targetNode / sh:targetSubjectsOf — they never owl:imports the class graph (ODR-0004 §3a three-graph separation; ODR-0010 §Q3).

Live count from sh:NodeShape declarations across the seven committed shapes files. SHACL property shapes (sh:property blocks) are blank nodes nested inside these node shapes and are resolved in the SHACL Play! rendering below — and natively on each shape's own page (the shape index that follows).

Shape index · 402 shapes, linked

Every node shape now has its own dereferenceable page at /pdtf/shape/{Name} — with its target and its constraints resolved with no blank nodes (path, datatype/class, cardinality, severity, message), the path linked to the property it constrains. Grouped by bounded-context module:

2 · The severity scheme — regulatory weight (ODR-0013)

Flat pass/fail buries the loudest error under noise. ODR-0013 (Guizzardi) ties the three SHACL severities to regulatory weight, not schema nesting: the rarest, most damaging error (identity loss) must be the loudest; the routine omission must be the quietest. Enforcement is a review rule — every sh:Violation shape must guard a Kind's identity contract or an unprovenanced claim; no optional-attribute gap may carry sh:Violation.

Counts are sh:severity assignments across the committed shapes graph. The dominance of sh:Violation reflects the 365 identity-and-typing shapes in §3; sh:Info/sh:Warning are the quality and sensitivity layers.

3 · Domain/range as constraint — 365 shapes (ODR-0029 R3)

ODR-0029 R3 drew the inference/validation boundary sharply: rdfs:domain / rdfs:range on the OWL properties are documentary, never materialised by OPDA's Safe-Group closure (which deliberately excludes the domain/range rules — ODR-0025 §R7, so a naive consumer's EPCCertificate ⊑ Property mis-inference is a consumer-side trap, not a fact in OPDA's graph). The enforceable typing is carried instead as SHACL: sh:targetSubjectsOf a property → sh:class on the subject (domain-as-constraint), and sh:targetObjectsOf → sh:class on the object (range-as-constraint).

This is the same value-keyed enforcement doctrine the classification layer uses (ODR-0027): constraints are keyed to the property in use, not to a class membership a reasoner must first entail. It keeps the closure at zero added triples over the flat schema while the SHACL graph carries every real obligation. ODR-0029 R3 records 273 such shapes; the live count above re-reads them from the committed corpus on every build.

4 · Asserted vs entailed & SHACL-AF

A soundness condition binds this layer (Knublauch): asserted is never rendered as entailed, and every shape states the graph it targets plus its validator-capability caveat. Two distinct things must not be confused:

• Validation (SHACL, closed-world). What the author wants checked — cardinality, datatype, identity-key presence, value-set membership, the domain/range shapes of §3. sh:minCount 1 is not owl:minCardinality 1: the first is a closed-world obligation, the second an open-world entailment licence.
• Inference (the frozen rule fragment, open-world). What the author wants in the closure — subclass / subproperty / inverse / symmetric / transitive (the 7 sound-but-RL-incomplete rules of config/opda-rdfs-plus.rules; not an OWL 2 RL reasoner, ODR-0029 R5). It materialises into a separate derived graph and adds 0 triples over the flat schema today.

5 · SHACL Play! — the SHACL reference rendering

Of the bake-off tools (ADR-0041), the OWL generators (pyLODE, WIDOCO, Ontospy) all score None on SHACL — they document the class graph and skip the shapes. Sparna's SHACL Play! is the only one that documents SHACL: it resolves all the blank nodes (the nested sh:property shapes that the inventory above counts but cannot name) into a readable per-shape reference. It is the authoritative term-by-term surface for this layer.

Open the SHACL Play! rendering ↗

Related

The shapes that overlays add are catalogued on Overlay profiles & gaps; the worked instance graphs each shape is exercised against are on Exemplars. The merged shapes graph download and the 24 per-module TTLs are linked from the artefacts index on the section overview. Governing records: ODR-0013 (severity), ODR-0029 (domain/range-as-constraint + inference boundary), ODR-0017 (SHACL-AF quality rules), ODR-0010 (overlay sh:xone).