= RDF 2 GeoJSON

This repository defines a conversion process for RDF data to GeoJSON and implements a version of it in Python.

See the convert.convert() function which does all the work.

Whatever RDF you give it, the conversion function will return either:

1. a valid geojson.FeatureCollection Python object, or
2. an empty Python dictionary

A valid result can be serialized to GeoJSON like this:

from rdflib import Graph from rdf2geojson import convert from geojson import dumps

gj = convert(Graph().parse(rdf_file)) dumps(gj)

The criteria for creating a valid FeatureCollection output are:

• the input must be valid RDF
• it must also be valid GeoSPARQL
• it must contain all the GeoSPARQL parts necessary for valid GeoJSON ** See the GeoSPARQL -> GeoJSON specification below

== GeoSPARQL -> GeoJSON specification below

GeoSPARQL knows about the following main object classes:

• FeatureCollection
• Feature
• GeometryCollection
• Geometry
• types of geometry: MultiPolygon Polygon MultiLineString LineString MultiPoint Point

The following rules are used to translate these classes to parts of GeoJSON:

1. FeatureCollection -> GeoJSON FeatureCollection
   • if no FeatureCollection is present in the RDF, one will be created in the GeoJSON
2. Feature -> GeoJSON Feature
3. GeometryCollection currently has no mapping
4. Geometry -> the geometry of a Feature and such objects are ignored stand-alone Geometries are not handled multiple geometries are not handled - only the first is used
5. types of geometry: all types of geometry are supported only WKT and GeoJSON serializations are currently supported
6. properties for Feature instances, other than Geometry instances, are added as GeoJSON key/valu pair properties

== License, Use & Contributing

This code is made available for use using the https://opensource.org/license/BSD-3-clause[BSD 3-Clause] license. See the LICENSE file for the deed.

This content is all copyrighted as follows:

© KurrawongAI, 2024

This code will always use this license, so contributors may contribute knowing this code will always be freely available for use.

== Tests

Tests can be run using the Taskfile like this:

task tests

== Development Roadmap

See the https://github.com/Kurrawong/rdf-to-geojson/issues[Issue Tracker] for this project, as well as TODO: items within the codebase.

== Contact

Nicholas J. Car + https://kurrawong.ai[KurrawongAI] + nick@kurrawong.net