README.md

GitHub geoJSON Data Provider Sample

This is a sample Data Provider for the node-geoservices-adaptor.

It provides access to geoJSON files stored in GitHub by providing a wrapper around GeoHub.

##GitHub Repository To reference a geoJSON file from a GitHub repository, use the following REST URL structure:

/geohub/rest/services/repo+<GitHub Username>+<Repo Name>+<File Name>/FeatureServer/0

Where:

• <GitHub Username> is a GitHub username.
• <Repo Name> is the name of a repo owned by the specified GitHub User.
• <File Name> is the name (without the .geojson extension) of a geoJSON file within the specified repo. It should be URL Encoded. It may include a relative path within the repository.

Below is a sample URL that you can add directly to an ArcGIS Online map or consume with one of the ArcGIS APIs:

• Access forks.geojson in chelm's grunt-geo repo: http://geonode.geeknixta.com/geohub/rest/services/repo+chelm+grunt-geo+forks/FeatureServer/0
• Access samples/bower.geojson in chelm's grunt-geo repo: http://geonode.geeknixta.com/geohub/rest/services/repo+chelm+grunt-geo+samples%2Fbower/FeatureServer/0

##GitHub Gist

To reference a geoJSON file from a GitHub Gist, use the following REST URL structure:

/geohub/rest/services/gist+<GistId>/FeatureServer/<FileIndex>

Where:

• <GistId> is the ID of the gist, which is included in the Gist's URL
• <FileIndex> is a zero-based reference to a geoJSON file in the Gist. Note that non-geoJSON files are ignored. That is, if there are 5 files in the gist, but only 2 geoJSON files, valid values for <FileIndex> are 0 and 1.

Below are some sample URLs that you can add directly to an ArcGIS Online map or consume with one of the ArcGIS APIs:

• Access the first geoJSON file in gist 6178185: http://geonode.geeknixta.com/geohub/rest/services/gist+6178185/FeatureServer/0
• Access the second geoJSON file in gist 6178185: http://geonode.geeknixta.com/geohub/rest/services/gist+6178185/FeatureServer/1

##Notes ###geoJSON containing multiple geometry types

An ArcGIS Feature Layer can only provide a single type of Esri Geometry. However, geoJSON files may contain any combination of Geometry Types. The GeoHub Data Provider defaults to outputting only geometries matching the type of the first geometry encountered in the geoJSON file. In the case where the geoJSON includes multiple Geometry Types and the first geometry in the geoJSON file is not the type you want to provide, add the optional +<GeometryType> specifier like this:

Repository:

/geohub/rest/services/repo+<GitHub Username>+<Repo Name>+<File Name>+<GeometryType>/FeatureServer/0

Gist:

/geohub/rest/services/gist+<GistId>+<GeometryType>/FeatureServer/<FileIndex>

Where <GeometryType> is a valid geoJSON Geometry Type as specified by the geoJSON Specification.

Please note:

• As per the specification, Geometry Types are case-sensitive.
• GeometryCollection is not supported.

Below are some sample URLs that you can add directly to an ArcGIS Online map or consume with one of the ArcGIS APIs:

#####Repository:

• Access forks.geojson in chelm's grunt-geo repo, filtering by geometry type LineString: http://geonode.geeknixta.com/geohub/rest/services/repo+chelm+grunt-geo+forks+LineString/FeatureServer/0
• Access samples/bower.geojson in chelm's grunt-geo repo, filtering by geometry type LineString: http://geonode.geeknixta.com/geohub/rest/services/repo+chelm+grunt-geo+samples%2Fbower+LineString/FeatureServer/0

#####Gist:

• Access the second geoJSON file in gist 6178185 and view only Point geometries: http://geonode.geeknixta.com/geohub/rest/services/gist+6178185+Point/FeatureServer/1

###GeoHub This adaptor makes use of GeoHub.