SHACL

This document contains a short introduction to RDF using rudof.

Preliminaries: Install and configure rudof

The library is available as pyrudof.

# @title
!pip install pyrudof

from pyrudof import Rudof, RudofConfig, RudofError
rudof = Rudof(RudofConfig())

Requirement already satisfied: pyrudof in /opt/hostedtoolcache/Python/3.11.15/x64/lib/python3.11/site-packages (0.2.9)

Validate using SHACL

# @title
rudof = Rudof(RudofConfig())

Let’s read some RDF data.

rudof.read_data("""
prefix :       <http://example.org/>
prefix xsd:    <http://www.w3.org/2001/XMLSchema#>
prefix rdf:    <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
prefix schema: <http://schema.org/>
prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#>

:timbl  rdf:type    :Human ;
        :name       "Tim Berners-Lee" ;
        :birthPlace :london ;
        :birthDate  "1955-06-08"^^xsd:date ;
        :employer   :CERN ;
        :knows      _:1 .
:london rdf:type    :city, :metropolis ;
        :country    :UK .
:CERN   rdf:type    :Organization .
_:1     :birthPlace :Spain .
""")

rudof.read_shacl("""
prefix :       <http://example.org/>
prefix sh:     <http://www.w3.org/ns/shacl#>
prefix xsd:    <http://www.w3.org/2001/XMLSchema#>
prefix rdfs:   <http://www.w3.org/2000/01/rdf-schema#>
prefix schema: <http://schema.org/>

:Person a sh:NodeShape ;
 sh:targetClass :Human ;
 sh:property [ sh:path :name ;
               sh:datatype xsd:string;
               sh:minCount 1 ; sh:maxCount 1 ] ;
 sh:property [ sh:path :birthDate ; sh:datatype xsd:date;
                                    sh:maxCount 1 ] ;
 sh:property [ sh:path :birthPlace ;
               sh:node :Place; sh:maxCount 1 ] ;
 sh:property [
    sh:path :employer ;
    sh:node :Organization
] .

:Place a sh:NodeShape .
:Organization a sh:NodeShape .
""")

rudof.validate_shacl()
result = rudof.serialize_shacl_validation_results()
print(result)

No Errors found

The previous data didn’t have errors. We can add some data with errors like the following:

rudof.read_data("""
prefix :       <http://example.org/>
prefix xsd:    <http://www.w3.org/2001/XMLSchema#>
prefix rdf:    <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
prefix schema: <http://schema.org/>
prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#>

:wrong1 rdf:type    :Human ;
        :name       "John" ;
        :birthDate  "1955-06-08"^^xsd:date, "1956-06-08"^^xsd:date .
:wrong2 rdf:type    :Human ;
        :name       23 ;
        :birthDate  "1955-06-08"^^xsd:date .
""", merge = True)

rudof.validate_shacl()
result = rudof.serialize_shacl_validation_results()
print(result)

╭────────────────────────────────────────┬─────────┬───────────────────────────────────────┬────────────┬───────┬────────────────────────────────────┬───────────────────────────────╮
│ Severity                               │ Node    │ Component                             │ Path       │ Value │ Source shape                       │ Details                       │
├────────────────────────────────────────┼─────────┼───────────────────────────────────────┼────────────┼───────┼────────────────────────────────────┼───────────────────────────────┤
│ <http://www.w3.org/ns/shacl#Violation> │ :wrong2 │ <http://www.w3.org/ns/shacl#datatype> │ :name      │ 23    │ _:dc37a82a8924decfbf01954a654842a7 │ Expected datatype: xsd:string │
├────────────────────────────────────────┼─────────┼───────────────────────────────────────┼────────────┼───────┼────────────────────────────────────┼───────────────────────────────┤
│ <http://www.w3.org/ns/shacl#Violation> │ :wrong1 │ <http://www.w3.org/ns/shacl#maxCount> │ :birthDate │       │ _:cd7d3e93b6ab85fac64dbbefac4c8c8f │ MaxCount(1) not satisfied     │
╰────────────────────────────────────────┴─────────┴───────────────────────────────────────┴────────────┴───────┴────────────────────────────────────┴───────────────────────────────╯