jsonld

JSON for Linking Data

JSON-LD is a light-weight syntax for expressing linked data. It is primarily intended for web-based programming environments, interoperable web services and for storing linked data in JSON-based databases. This package provides bindings to the JavaScript library for converting, expanding and compacting JSON-LD documents.

Hello World

Example from https://github.com/digitalbazaar/jsonld.js#quick-examples. Example data:

doc <- '{
  "http://schema.org/name": "Manu Sporny",
  "http://schema.org/url": {"@id": "http://manu.sporny.org/"},
  "http://schema.org/image": {"@id": "http://manu.sporny.org/images/manu.png"}
}'

context <- '{
  "name": "http://schema.org/name",
  "homepage": {"@id": "http://schema.org/url", "@type": "@id"},
  "image": {"@id": "http://schema.org/image", "@type": "@id"}
}'

Compact and expand:

(out <- jsonld_compact(doc, context))

{
  "@context": {
    "name": "http://schema.org/name",
    "homepage": {
      "@id": "http://schema.org/url",
      "@type": "@id"
    },
    "image": {
      "@id": "http://schema.org/image",
      "@type": "@id"
    }
  },
  "image": "http://manu.sporny.org/images/manu.png",
  "name": "Manu Sporny",
  "homepage": "http://manu.sporny.org/"
} 

(expanded <- jsonld_expand(out))

[
  {
    "http://schema.org/url": [
      {
        "@id": "http://manu.sporny.org/"
      }
    ],
    "http://schema.org/image": [
      {
        "@id": "http://manu.sporny.org/images/manu.png"
      }
    ],
    "http://schema.org/name": [
      {
        "@value": "Manu Sporny"
      }
    ]
  }
] 

Convert between JSON and RDF:

cat(nquads <- jsonld_to_rdf(doc))

_:b0 <http://schema.org/image> <http://manu.sporny.org/images/manu.png> .
_:b0 <http://schema.org/name> "Manu Sporny" .
_:b0 <http://schema.org/url> <http://manu.sporny.org/> .

jsonld_from_rdf(nquads)

[
  {
    "@id": "_:b0",
    "http://schema.org/image": [
      {
        "@id": "http://manu.sporny.org/images/manu.png"
      }
    ],
    "http://schema.org/name": [
      {
        "@value": "Manu Sporny"
      }
    ],
    "http://schema.org/url": [
      {
        "@id": "http://manu.sporny.org/"
      }
    ]
  }
] 

Other utilities:

jsonld_flatten(doc)

[
  {
    "@id": "_:b0",
    "http://schema.org/image": [
      {
        "@id": "http://manu.sporny.org/images/manu.png"
      }
    ],
    "http://schema.org/name": [
      {
        "@value": "Manu Sporny"
      }
    ],
    "http://schema.org/url": [
      {
        "@id": "http://manu.sporny.org/"
      }
    ]
  }
] 

cat(jsonld_normalize(doc, algorithm = 'URDNA2015', format = 'application/nquads'))

_:c14n0 <http://schema.org/image> <http://manu.sporny.org/images/manu.png> .
_:c14n0 <http://schema.org/name> "Manu Sporny" .
_:c14n0 <http://schema.org/url> <http://manu.sporny.org/> .