MatejLach / json-gold

A JSON-LD processor for Go

JSON-goLD

This library is an implementation of the JSON-LD 1.0 specification in Go. It supports both URDNA2015 and URGNA2012 RDF dataset normalisation algorithms.

The original library was written by Stan Nazarenko (@kazarena). See the full list of contributors here.

Testing & Compliance

As of December 1, 2017:

• all JSON-LD 1.0 tests from the official JSON-LD test suite pass
• all RDF Dataset Normalisation tests from the current test suite pass
• JSON-LD 1.1 spec is not currenty supported

Inspiration

This implementation was heavily influenced by JSONLD-Java with some techniques borrowed from PyLD and gojsonld. Big thank you to the contributors of the forementioned libraries for figuring out implementation details of the core algorithms.

Examples

Expand

See complete code in examples/expand.go.

proc := ld.NewJsonLdProcessor()
options := ld.NewJsonLdOptions("")

// expanding remote document

expanded, err := proc.Expand("http://json-ld.org/test-suite/tests/expand-0002-in.jsonld", options)
if err != nil {
	log.Println("Error when expanding JSON-LD document:", err)
	return
}

// expanding in-memory document

doc := map[string]interface{}{
	"@context": "http://schema.org/",
	"@type": "Person",
	"name": "Jane Doe",
	"jobTitle": "Professor",
	"telephone": "[phone]",
	"url": "http://www.janedoe.com",
}

expanded, err = proc.Expand(doc, options)

Compact

See complete code in examples/compact.go.

proc := ld.NewJsonLdProcessor()
options := ld.NewJsonLdOptions("")

doc := map[string]interface{}{
	"@id": "http://example.org/test#book",
	"http://example.org/vocab#contains": map[string]interface{}{
		"@id": "http://example.org/test#chapter",
	},
	"http://purl.org/dc/elements/1.1/title": "Title",
}

context := map[string]interface{}{
	"@context": map[string]interface{}{
		"dc": "http://purl.org/dc/elements/1.1/",
		"ex": "http://example.org/vocab#",
		"ex:contains": map[string]interface{}{
			"@type": "@id",
		},
	},
}

compactedDoc, err := proc.Compact(doc, context, options)

Flatten

See complete code in examples/flatten.go.

proc := ld.NewJsonLdProcessor()
options := ld.NewJsonLdOptions("")

doc := map[string]interface{}{
	"@context": []interface{}{
		map[string]interface{}{
			"name": "http://xmlns.com/foaf/0.1/name",
			"homepage": map[string]interface{}{
				"@id": "http://xmlns.com/foaf/0.1/homepage",
				"@type": "@id",
			},
		},
		map[string]interface{}{
			"ical": "http://www.w3.org/2002/12/cal/ical#",
		},
	},
	"@id": "http://example.com/speakers#Alice",
	"name": "Alice",
	"homepage": "http://xkcd.com/177/",
	"ical:summary": "Alice Talk",
	"ical:location": "Lyon Convention Centre, Lyon, France",
}

flattenedDoc, err := proc.Flatten(doc, nil, options)

Frame

See complete code in examples/frame.go.

proc := ld.NewJsonLdProcessor()
options := ld.NewJsonLdOptions("")

doc := map[string]interface{}{
	"@context": map[string]interface{}{
		"dc": "http://purl.org/dc/elements/1.1/",
		"ex": "http://example.org/vocab#",
		"ex:contains": map[string]interface{}{"@type": "@id"},
	},
	"@graph": []interface{}{
		map[string]interface{}{
			"@id": "http://example.org/test/#library",
			"@type": "ex:Library",
			"ex:contains": "http://example.org/test#book",
		},
		map[string]interface{}{
			"@id": "http://example.org/test#book",
			"@type": "ex:Book",
			"dc:contributor": "Writer",
			"dc:title": "My Book",
			"ex:contains": "http://example.org/test#chapter",
		},
		map[string]interface{}{
			"@id": "http://example.org/test#chapter",
			"@type": "ex:Chapter",
			"dc:description": "Fun",
			"dc:title": "Chapter One",
		},
	},
}

frame := map[string]interface{}{
	"@context": map[string]interface{}{
		"dc": "http://purl.org/dc/elements/1.1/",
		"ex": "http://example.org/vocab#",
	},
	"@type": "ex:Library",
	"ex:contains": map[string]interface{}{
		"@type": "ex:Book",
		"ex:contains": map[string]interface{}{
			"@type": "ex:Chapter",
		},
	},
}

framedDoc, err := proc.Frame(doc, frame, options)

To RDF

See complete code in examples/to_rdf.go.

proc := ld.NewJsonLdProcessor()
options := ld.NewJsonLdOptions("")
options.Format = "application/nquads"

// this JSON-LD document was taken from http://json-ld.org/test-suite/tests/toRdf-0028-in.jsonld
doc := map[string]interface{}{
	"@context": map[string]interface{}{
		"sec":        "http://purl.org/security#",
		"xsd":        "http://www.w3.org/2001/XMLSchema#",
		"rdf":        "http://www.w3.org/1999/02/22-rdf-syntax-ns#",
		"dc":         "http://purl.org/dc/terms/",
		"sec:signer": map[string]interface{}{"@type": "@id"},
		"dc:created": map[string]interface{}{"@type": "xsd:dateTime"},
	},
	"@id":                "http://example.org/sig1",
	"@type":              []interface{}{"rdf:Graph", "sec:SignedGraph"},
	"dc:created":         "2011-09-23T20:21:34Z",
	"sec:signer":         "http://payswarm.example.com/i/john/keys/5",
	"sec:signatureValue": "OGQzNGVkMzVm4NTIyZTkZDYMmMzQzNmExMgoYzI43Q3ODIyOWM32NjI=",
	"@graph": map[string]interface{}{
		"@id":      "http://example.org/fact1",
		"dc:title": "Hello World!",
	},
}
triples, err := proc.ToRDF(doc, options)

From RDF

See complete code in examples/from_rdf.go.

proc := ld.NewJsonLdProcessor()
options := ld.NewJsonLdOptions("")

triples := `
	<http://example.com/Subj1> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://example.com/Type> .
	<http://example.com/Subj1> <http://example.com/prop1> <http://example.com/Obj1> .
	<http://example.com/Subj1> <http://example.com/prop2> "Plain" .
	<http://example.com/Subj1> <http://example.com/prop2> "2012-05-12"^^<http://www.w3.org/2001/XMLSchema#date> .
	<http://example.com/Subj1> <http://example.com/prop2> "English"@en .
`

doc, err := proc.FromRDF(triples, options)

Normalize

See complete code in examples/normalize.go.

proc := ld.NewJsonLdProcessor()
options := ld.NewJsonLdOptions("")
options.Format = "application/nquads"
options.Algorithm = "URDNA2015"

doc := map[string]interface{}{
	"@context": map[string]interface{}{
		"ex": "http://example.org/vocab#",
	},
	"@id": "http://example.org/test#example",
	"@type": "ex:Foo",
	"ex:embed": map[string]interface{}{
		"@type": "ex:Bar",
	},
}

normalizedTriples, err := proc.Normalize(doc, options)