geojson-ld

Describing and extending GeoJSON with JSON-LD

JSON-LD is JSON for linking data and it's a web standard: http://www.w3.org/TR/json-ld/. It offers a path for upgrading existing GeoJSON data.

A JSON-LD context defines terms and other things and allows GeoJSON documents to be more specific about data, e.g, what "type" and "id" and the keys of "properties" mean to the rest of the web. Additionally, JSON-LD's "@type" and "@id" provide a means of integrating GeoJSON with other schemas.

This GeoJSON-LD project is focussed on publishing a vocabulary of GeoJSON terms and a base JSON-LD context for GeoJSON data, but also aims to help organizations develop good practices for upgrading GeoJSON data.

Example

Below is an example of using JSON-LD to declare that the features of a collection are also schema.org Places and that their "description" property is the same thing as a schema.org decription. Bringing optional namespaces to the "properties" grab bag is perhaps the best thing that JSON-LD can do for GeoJSON data. Note that http://example.com/vocab# is used as the @vocab URI until GeoJSON-LD is published.

{ 
  "@context": {
    "@vocab": "http://example.com/vocab#",
    "Place": "http://schema.org/Place",
    "name": "http://schema.org/name"
  },
  "type": "FeatureCollection",
  "@id": "http://example.com/collections/1",
  "features": [
    { 
      "type": "Feature",
      "@type": ["Feature", "Place"],
      "id": "1",
      "@id": "http://example.com/collections/1/features/1",
      "properties": {"name": "Fort Collins, Colorado" },
      "geometry": {"type": "Point", "coordinates": [-105.078056, 40.559167]}
    },
    { 
      "type": "Feature",
      "@type": ["Feature", "Place"],
      "id": "2",
      "@id": "http://example.com/collections/1/features/2",
      "properties": {"name": "Boulder, Colorado" },
      "geometry": {"type": "Point", "coordinates": [-105.251945, 40.027435]}
    }
  ]
}

Paste the JSON text above into a Gist like this and you'll see that it's ordinary GeoJSON as well as linked data.

Development

This is a work in progress. See https://github.com/geojson/geojson-ld/issues.

A demo vocabulary including the GeoJSON terms above is online at http://geojson.org/vocab.