JSON-LD

JSON-LD

Filename extension	.jsonld
Internet media type	application/ld+json
Type of format	Semantic Web
Container for	Linked Data
Extended from	JSON
Standard	JSON-LD 1.0 / JSON-LD 1.0 API
Free format?	Yes

JSON-LD 1.0 - A JSON-based Serialization for Linked Data

Abbreviation	JSON-LD
Status	W3C Recommendation
Year started	2015
Editors	Manu Sporny, Gregg Kellogg, Markus Lanthaler
Authors	Manu Sporny, Dave Longley, Gregg Kellogg, Markus Lanthaler, Niklas Lindström
Base standards	JSON, RDF
Domain	Semantic Web, Data Serialization
Website	JSON-LD 1.0

JSON-LD 1.0 Processing Algorithms and API

Abbreviation	JSON-LD-API
Status	W3C Recommendation
Year started	2015
Editors	Markus Lanthaler, Gregg Kellogg, Manu Sporny
Authors	Dave Longley, Gregg Kellogg, Markus Lanthaler, Manu Sporny
Base standards	JSON-LD
Domain	Semantic Web, API, Algorithm
Website	JSON-LD 1.0 API

JSON-LD, or JavaScript Object Notation for Linked Data, is a method of transporting Linked Data using JSON. It was a goal to require as little effort as possible from developers to transform their existing JSON to JSON-LD. This allows data to be serialized in a way that is similar to traditional JSON. It is a World Wide Web Consortium Recommendation that has been developed by the JSON for Linking Data Community Group before it has been transferred to the RDF Working Group for review, improvement, and standardization.

JSON-LD is designed around the concept of a "context" to provide additional mappings from JSON to an RDF model. The context links object properties in a JSON document to concepts in an ontology. In order to map the JSON-LD syntax to RDF, JSON-LD allows values to be coerced to a specified type or to be tagged with a language. A context can be embedded directly in a JSON-LD document or put into a separate file and referenced from different documents (from traditional JSON documents via an HTTP Link header).

Example

{
  "@context": {
    "name": "http://xmlns.com/foaf/0.1/name",
    "homepage": {
      "@id": "http://xmlns.com/foaf/0.1/workplaceHomepage",
      "@type": "@id"
    },
    "Person": "http://xmlns.com/foaf/0.1/Person"
  },
  "@id": "http://me.markus-lanthaler.com",
  "@type": "Person",
  "name": "Markus Lanthaler",
  "homepage": "http://www.tugraz.at/"
}

The example above describes a person, based on the FOAF vocabulary. First, the two JSON properties name and homepage and the type person are mapped to concepts in the FOAF vocabulary and the value of the homepage property is specified to be of the type @id, i.e., it is specified to be an IRI in the context definition. Based on the RDF model, this allows the person described in the document to be unambiguously identified by an IRI. The use of resolvable IRIs allows RDF documents containing more information to be transcluded which enables clients to discover new data by simply following those links; this principle is known as Follow Your Nose.

By having all data semantically annotated as in the example, an RDF processor can identify that the document contains information about a person (@type) and if the processor understands the FOAF vocabulary it can determine which properties specify the person’s name and homepage.

External links

• JSON-LD.org