glam/RDF_GENERATION_SUMMARY.md

RDF Generation Summary: Multi-Aspect Custodian Schema

Date: 2025-11-22
Status: ✅ ALL FORMATS GENERATED SUCCESSFULLY

Overview

Successfully generated all 4 RDF serialization formats from the multi-aspect custodian schema (01_custodian_name_modular.yaml).

Generation Process

Key Issue Resolved: gen-owl Warning Interference

Problem: gen-owl writes WARNING messages to stdout, which contaminated the TTL output and broke downstream rdfpipe parsing.

Solution: Redirect stderr when generating RDF formats:

# Correct command pattern
gen-owl -f ttl schema.yaml 2>/dev/null > output.owl.ttl
rdfpipe -i turtle -o format output.owl.ttl > output.format 2>/dev/null

Additional Fixes Required

1. Import Path Corrections (3 files):

   • modules/classes/CustodianPlace.yaml - Changed - Custodian → - ./Custodian
   • modules/classes/CustodianName.yaml - Changed - Custodian → - ./Custodian
   • modules/classes/CustodianLegalStatus.yaml - Changed - Custodian → - ./Custodian

   Reason: LinkML requires relative paths for module imports

2. Timestamp Implementation:

   • All generated files now include timestamps per .opencode/SCHEMA_GENERATION_RULES.md
   • Format: {base_name}_{YYYYMMDD}_{HHMMSS}.{extension}

Generated Files

Timestamp: 20251122_154430

Format	Filename	Size	Lines	Description
OWL/Turtle	custodian_multi_aspect_20251122_154430.owl.ttl	159KB	2,619	Primary RDF format (human-readable)
N-Triples	custodian_multi_aspect_20251122_154430.nt	456KB	3,027	Triple-per-line format (machine-optimized)
JSON-LD	custodian_multi_aspect_20251122_154430.jsonld	380KB	14,094	JSON-LD (web-friendly)
RDF/XML	custodian_multi_aspect_20251122_154430.rdf	328KB	4,585	XML serialization (legacy compatibility)

Total: 1.3MB across 4 formats

Validation Results

Schema Validation ✅

• ✅ All imports resolved correctly
• ✅ No critical LinkML errors
• ✅ All classes defined (CustodianLegalStatus, CustodianName, CustodianPlace)
• ✅ All enums defined (PlaceSpecificityEnum, etc.)
• ✅ All 61 slots defined

Content Verification ✅

OWL/Turtle (custodian_multi_aspect_20251122_154430.owl.ttl):

• ✅ Valid Turtle syntax
• ✅ Ontology metadata present (title, version, license)
• ✅ All class definitions present
• ✅ All property definitions present
• ✅ SKOS documentation included

N-Triples (custodian_multi_aspect_20251122_154430.nt):

• ✅ Valid N-Triples syntax
• ✅ 3,027 triples generated
• ✅ All statements expanded

JSON-LD (custodian_multi_aspect_20251122_154430.jsonld):

• ✅ Valid JSON-LD syntax
• ✅ @context included
• ✅ 14,094 lines (expanded representation)
• ✅ All class/property URIs resolved

RDF/XML (custodian_multi_aspect_20251122_154430.rdf):

• ✅ Valid XML syntax
• ✅ Namespace declarations present
• ✅ 4,585 lines
• ✅ rdf:Description elements properly formed

Reference Classes Verified

Confirmed presence in RDF output:

• ✅ CustodianLegalStatus (34 references) - Formal legal entities
• ✅ CustodianName (existing) - Emic labels
• ✅ CustodianPlace (15 references) - Nominal place designations
• ✅ PlaceSpecificityEnum (21 references) - Place specificity levels
• ✅ Custodian (hub) - Central entity aggregating aspects
• ✅ CustodianObservation - Source evidence
• ✅ ReconstructionActivity - PROV-O activity linking observations to aspects

Ontology Alignments Verified

Class Mappings ✅

Class	Ontology Mapping	Status
CustodianLegalStatus	org:FormalOrganization	✅ Present
CustodianName	skos:Concept	✅ Present
CustodianPlace	crm:E53_Place	✅ Present
Custodian	prov:Entity	✅ Present
ReconstructionActivity	prov:Activity	✅ Present

Property Mappings ✅

Slot	Ontology Mapping	Status
legal_entity_type	org:classification	✅ Present
legal_form	tooi:organisatievorm	✅ Present
place_name	crm:P87_is_identified_by	✅ Present
preferred_label	skos:prefLabel	✅ Present
name_authority	prov:wasAttributedTo	✅ Present

Known Issues

Non-Critical Warnings (Suppressed with 2>/dev/null)

1. Namespace Conflicts:

   • schema.org mapped to both http:// and https:// versions
   • Does not affect RDF validity
   • Consider consolidating to HTTPS in future version

2. Import Resolution:

   • Fixed: Bare class names in imports (e.g., - Custodian) now use relative paths (- ./Custodian)
   • All imports now resolve correctly

Usage Examples

Loading into RDF Database

Apache Jena (Fuseki):

# Load Turtle format (most efficient)
tdbloader --loc=/path/to/tdb custodian_multi_aspect_20251122_154430.owl.ttl

RDF4J:

# Upload any format via HTTP
curl -X POST -H "Content-Type: text/turtle" \
  --data-binary @custodian_multi_aspect_20251122_154430.owl.ttl \
  http://localhost:8080/rdf4j-server/repositories/heritage

SPARQL Query Example

PREFIX hc: <https://nde.nl/ontology/hc/>
PREFIX crm: <http://www.cidoc-crm.org/cidoc-crm/>
PREFIX org: <http://www.w3.org/ns/org#>

# Find all custodians with legal status and place designations
SELECT ?custodian ?legalName ?placeName WHERE {
  ?custodian a hc:Custodian .
  ?custodian hc:legal_status ?legal .
  ?legal hc:legal_name ?legalName .
  ?custodian hc:place_designation ?place .
  ?place hc:place_name ?placeName .
}

Python RDFLib Usage

from rdflib import Graph

# Load any format
g = Graph()
g.parse("custodian_multi_aspect_20251122_154430.owl.ttl", format="turtle")

# Or JSON-LD
g.parse("custodian_multi_aspect_20251122_154430.jsonld", format="json-ld")

# Query
results = g.query("""
    SELECT ?class WHERE {
        ?class a owl:Class .
    }
""")

for row in results:
    print(row.class)

Generation Commands (For Reference)

# Set timestamp
TIMESTAMP=$(date +%Y%m%d_%H%M%S)

# Generate OWL/Turtle (primary format)
gen-owl -f ttl schemas/20251121/linkml/01_custodian_name_modular.yaml \
    2>/dev/null > "schemas/20251121/rdf/custodian_multi_aspect_${TIMESTAMP}.owl.ttl"

# Convert to N-Triples
rdfpipe -i turtle -o nt "schemas/20251121/rdf/custodian_multi_aspect_${TIMESTAMP}.owl.ttl" \
    2>/dev/null > "schemas/20251121/rdf/custodian_multi_aspect_${TIMESTAMP}.nt"

# Convert to JSON-LD
rdfpipe -i turtle -o json-ld "schemas/20251121/rdf/custodian_multi_aspect_${TIMESTAMP}.owl.ttl" \
    2>/dev/null > "schemas/20251121/rdf/custodian_multi_aspect_${TIMESTAMP}.jsonld"

# Convert to RDF/XML
rdfpipe -i turtle -o xml "schemas/20251121/rdf/custodian_multi_aspect_${TIMESTAMP}.owl.ttl" \
    2>/dev/null > "schemas/20251121/rdf/custodian_multi_aspect_${TIMESTAMP}.rdf"

Next Steps

Immediate

• All RDF formats generated successfully
• All formats validated
• Documentation updated

Short-term

• Resolve schema.org namespace conflict (http vs https)
• Generate additional serialization formats:
  • N3 (Notation3)
  • TriG (named graphs)
  • TriX (XML with named graphs)
• Create RDF validation test suite

Medium-term

• Load into triple store (Apache Jena / RDF4J)
• Create example SPARQL queries
• Generate schema documentation from RDF (LODE, pyLODE)
• Publish schema to W3C namespace (if applicable)

File Locations

Schema Source:

• schemas/20251121/linkml/01_custodian_name_modular.yaml

Generated RDF:

• schemas/20251121/rdf/custodian_multi_aspect_20251122_154430.owl.ttl
• schemas/20251121/rdf/custodian_multi_aspect_20251122_154430.nt
• schemas/20251121/rdf/custodian_multi_aspect_20251122_154430.jsonld
• schemas/20251121/rdf/custodian_multi_aspect_20251122_154430.rdf

Example Instance:

• schemas/20251121/examples/multi_aspect_rijksmuseum_complete.yaml

Documentation:

• QUICK_STATUS_CUSTODIAN_SCHEMA_MOD_20251122.md
• CUSTODIAN_MULTI_ASPECT_REFACTORING.md
• SESSION_SUMMARY_20251122_CUSTODIAN_MULTI_ASPECT.md
• .opencode/SCHEMA_GENERATION_RULES.md

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Verification Checklist

• OWL/Turtle validates (2,619 lines)
• N-Triples validates (3,027 lines)
• JSON-LD validates (14,094 lines)
• RDF/XML validates (4,585 lines)
• All classes present in RDF
• All properties present in RDF
• All enums present in RDF
• Ontology alignments verified
• Timestamps applied to all files
• Documentation updated
• Generation commands documented

---

Status: ✅ COMPLETE - ALL FORMATS GENERATED SUCCESSFULLY
Timestamp: 2025-11-22 15:44:30
Total Files: 4 RDF formats (1.3MB total)
Schema Version: v0.1.0
Multi-Aspect Architecture: Fully implemented and validated