Information Model - Contract Validation Demo

A short demonstration of how to validate RDF contracts according to the Information Model of the International Data Spaces Association using Python and SHACL.

What it does

This tool demonstrates the validation of contracts and usage policies in Python 3. To do so, it heavily relies on the Python modules pySHACL and rdflib. For a given RDF input serialized in turtle, xml, json-ld, nt or n3 the validation checks, if the input conforms to the SHACL shapes defined by the International Data Space Association - InformationModel.

How to use

Installation:

• Download this repository.
• Install the required python packages with PIP installer. (pip install -r requirements.txt)
• Download the IDSA Information Model repository.
• Copy the folder examples/contracts-and-usage-policy/templates into this directory, to provide the validator the necessary shape information. (Link to folder online) The resulting folder structure should look like this:

IM-ContractValidatorDemo
│───.gitignore
│───demo.py 
│───README.md
│
└───examples
│   │───valid_agreement.ttl
│   │───invalid_agreement.ttl
|   |───...
│   
└───templates
    │───<Classname>Templates
    |   |───<Classname>_TEMPLATE.jsonld
    |   |───<Classname>_TEMPLATE.ttl
    |   |───<Classname>TemplateShape.ttl
    │───...

Command Line Usage

python demo.py /path/to/dataFile.ttl

As output the result_text return value of pySHACLs validate function is printed to the console. This is the textual representation of the SHACL Validation Report.

Example:

$ python demo.py examples/invalid_offer.jsonld
Validation Report
Conforms: False
Results (3):

Constraint Violation in MinCountConstraintComponent (http://www.w3.org/ns/shacl#MinCountConstraintComponent):
        Severity: sh:Violation
        Source Shape: shapes:ConstraintTemplate-rightOperandPropertyShape
        Focus Node: [ <http://www.w3.org/ns/odrl/2/leftOperand> idsc:POLICY_EVALUATION_TIME ; <http://www.w3.org/ns/odrl/2/operator> idsc:AFTER ; ids:leftOperand idsc:POLICY_EVALUATION_TIME ; ids:operator idsc:AFTER ; rdf:type <http://www.w3.org/ns/odrl/2/Constraint>, ids:AbstractConstraint, ids:Constraint, rdfs:Resource ]
        Result Path: [ sh:alternativePath ( ids:rightOperand ids:rightOperandReference ) ]
        Message: <https://raw.githubusercontent.com/International-Data-Spaces-Association/InformationModel/master/examples/contract-and-usage-policy/templates/ConstraintTemplates/ConstraintTemplateShape.ttl> (ConstraintTemplate-rightOperandPropertyShape): In a _:Constraint one of the properties a) ids:rightOperand or b) ids:rightOperandReference must point to an adequate value according to the ids:LeftOperand used in this constraint.

Constraint Violation in MinCountConstraintComponent (http://www.w3.org/ns/shacl#MinCountConstraintComponent):
        Severity: sh:Violation
        Source Shape: shapes1:ObligationTemplate-assigneePropertyShape
        Focus Node: [ <http://www.w3.org/ns/odrl/2/action> idsc:LOG ; <http://www.w3.org/ns/odrl/2/assigner> <https://iais.fraunhofer.de/> ; ids:action idsc:LOG ; ids:assigner <https://iais.fraunhofer.de/> ; rdf:type <http://www.w3.org/ns/odrl/2/Duty>, <http://www.w3.org/ns/odrl/2/Rule>, ids:Described, ids:Duty, ids:Rule, ids:UsageControlObject, rdfs:Resource ]
        Result Path: ids:assignee
        Message: <https://raw.githubusercontent.com/International-Data-Spaces-Association/InformationModel/master/examples/contract-and-usage-policy/templates/ObligationTemplates/ObligationTemplateShapes.ttl> (ObligationTemplate-assigneePropertyShape): In a _:Duty for a _:ContractAgreement the ids:assignee property must point to exactly one participant. This can be a) an IRI or b) an ids:Participant. In a _:Duty for a _:ContractOffer or _:ContractRequest the ids:assignee property may still be missing.

Constraint Violation in NodeConstraintComponent (http://www.w3.org/ns/shacl#NodeConstraintComponent):
        Severity: sh:Violation
        Source Shape: shapes:OfferTemplateShape
        Focus Node: <https://mdmconnector.ids.isst.fraunhofer.de/ResourceCatalog/e75d21a7/offer1/>
        Value Node: <https://mdmconnector.ids.isst.fraunhofer.de/ResourceCatalog/e75d21a7/offer1/>
        Message: <https://raw.githubusercontent.com/International-Data-Spaces-Association/InformationModel/master/examples/contract-and-usage-policy/templates/OfferTemplateShape.ttl> (HasProviderOrConsumerNodeShape): In a _:ContractOffer a) the ids:provider property must point to one participant or b) the ids:consumer property must point to one participant  or c) the ids:provider and the ids:consumer must point to one participant. This can in any case be a) an IRI or b) an ids:Participant.