shacl-engine

A fast SHACL engine for data provided as RDF/JS objects.

Features

SHACL consists of multiple modules. Here is an overview of the features this library implements and planned features:

• [X] SHACL Validation
  • [X] SHACL Core Constraint Components
  • [X] SHACL SPARQL-based Constraints
• [ ] SHACL JavaScript Extensions
• [ ] SHACL Advanced Features

Install

npm install --save shacl-engine

Usage

Validator

The Validator class can be imported from the main package:

import { Validator } from 'shacl-engine'

Or from the class file:

import Validator from 'shacl-engine/Validator.js'

The constructor must be called with the shapes as an RDF/JS DatasetCore object. The second argument is an object for various options:

• coverage: Boolean flag to enable collecting covered quads. (optional) If coverage is enabled, debug, details, and trace are also enabled.
• debug: Generate debug results for successful validations. (optional)
• details: Generate nested result details. (optional)
• factory: A RDF/JS DataFactory, which is used to generate the report (required).
• trace: Generate results for path traversing. (optional)

The validations can be executed with the .validate(data, shapes) method. The data must have the following structure:

• dataset: An RDF/JS DatasetCore object that contains the quads. (required)
• terms: An iterable object of RDF/JS Terms that will be used as initial focus nodes. (optional)

The shapes object is optional, but if given must have the following structure:

• terms: An iterable object of RDF/JS Terms that refers to the initial set of shapes. (optional) This doesn't limit the nested shapes.

Example

The following example reads the shapes and data from the list coverage test, creates a Validator instance, and runs the validation:

import rdfDataModel from '@rdfjs/data-model'
import rdfDataset from '@rdfjs/dataset'
import toNT from '@rdfjs/to-ntriples'
import fromFile from 'rdf-utils-fs/fromFile.js'
import Validator from 'shacl-engine/Validator.js'

async function main () {
  // read the shape and data from the list coverage test
  const filename = new URL('../test/assets/coverage/list.ttl', import.meta.url)
  const dataset = rdfDataset.dataset()

  for await (const quad of fromFile(filename.pathname)) {
    dataset.add(quad)
  }

  // create a validator instance for the shapes in the given dataset
  const validator = new Validator(dataset, { factory: rdfDataModel })

  // run the validation process
  const report = await validator.validate({ dataset })

  // check if the data conforms to the given shape
  console.log(`conforms: ${report.conforms}`)
}

main()

See the examples folders for more examples.

SPARQL Support

The Validator comes with the core SHACL validations out-of-the-box. Additional validations must be added for SPARQL support. The validations can be imported from shacl-engine/sparql.js as shown below:

import rdfDataModel from '@rdfjs/data-model'
import { validations as sparqlValidations } from 'shacl-engine/sparql.js'

const validator = new Validator(dataset, {
  factory: rdfDataModel,
  validations: sparqlValidations
})