SHACL Viz

This tool allows you to visualize SHACL data model files as a UML-like class diagram with the following features:

• diagram nodes correspond to the target classes of sh:targetClass of sh:NodeShape, not the sh:NodeShape themselves.
• class labels are taken from dc:title of the node shapes (falling back to rdfs:label of the sh:targetClass)
• diagram edges correspond to sh:PropertyShapes
• their labels are taken from sh:name (falling back to sh:description)
• configurable RDFS classes/datatypes that will be visualized as fields (not edges) in the diagram.
• configurable filter to ignore certain domainClass-property-rangeClass combinations (e.g. to select only required elements for the diagram)
• export formats - PlantUML (auto-layout), TGF graph importable by yEd (for advanced layouts and manual editing)

Diagram Generation

The diagram generation works specific form of a SHACL file representing a data model with the following constraints:

• a node shape to be visualized must have
  • sh:targetClass pointing to an IRI of a class
• each property shape
  • must have an sh:path pointing to an IRI of a property.
  • can have optionally these properties
    • sh:datatype
    • sh:maxCount
    • sh:minCount
• labels are taken from rdfs:label of the target ontology class/ontology property in the path. In case there is a dc:title of the given class shape (resp. sh:name of the given property shape), it overrides the label of the ontology entity. If neither label is present, it is extracted from the IRI.

Minimal Example

export SHACL_FILE=src/test/resources/example.ttl
export OUTPUT_FILE=src/test/resources/example.puml
./gradlew run --args="$SHACL_FILE $OUTPUT_FILE"

This generates a PlantUML file taking into account all property shapes, and considering only data types as fields.

Make a class visualized as a field

echo "SELECT ?field {} VALUES ?field { <http://www.w3.org/2001/XMLSchema#string> <http://www.w3.org/2004/02/skos/core#Concept> }" > fieldQuery.rq 
export SHACL_FILE=src/test/resources/example.ttl
export OUTPUT_FILE=src/test/resources/example.puml
./gradlew run --args="$SHACL_FILE $OUTPUT_FILE --fieldQuery=fieldQuery.rq --hideOrphanNodes=false"

Generates the same diagram, but showing skos:Concept as fields instead of nodes. The --hideOrphanNodes=false flag ensures that the also nodes (here 'string') without any in/out links and fields are shown in the diagram.

Only visualize required edges/fields

export SHACL_FILE=src/test/resources/example.ttl
export OUTPUT_FILE=src/test/resources/example.puml
./gradlew run --args="$SHACL_FILE $OUTPUT_FILE --filterQuery=classpath:/edges-required-only.rq"

Filters out all constraints (edges/fields) that have minCount < 1.

Generate TGF for advanced layout

export SHACL_FILE=src/test/resources/example.ttl
export OUTPUT_FILE=src/test/resources/example.tgf
./gradlew run --args="$SHACL_FILE --outputFormat tgf $OUTPUT_FILE"

Generates a TGF graph.

1. Open the TGF file in yEd editor.
2. Execute "Fit Node to Size" and "Hierarchical Layout" (or choose another layout)
3. Perform any manual editing/layout
4. Save the diagram as GraphML/Export it to the desired format (e.g. svg/png)