Geo::JSON - Perl OO interface for geojson
use Geo::JSON; my $obj = Geo::JSON->from_json( $json ); $obj->to_json();
Convert to and from geojson using Perl objects. GeoJSON objects represent various geographical positions - points, lines, polygons, etc.
Currently supports 2 or 3 dimensions (longitude, latitude, altitude). Further dimensions in positions are ignored for calculations and comparisons, but will be read-from and written-to.
See: http://www.geojson.org/geojson-spec.html
See the specification for the full details, but the basics are as follows:
type
Determines the object the json will be turned into
position
Not explicitly named in the json, but an array of at least two numbers representing a location in x, y, z order (either Easting, Northing, Altitude or Longitude, Latitude, Altitude as appropriate).
Additional numbers may be present but ignored by this package for calculations.
coordinates
Defined in geometry objects (Point, MultiPoint, LineString, MultiLineString, Polygon, MultiPolygon). Will consist of a single position (Point), an array of positions (MultiPoint, LineString), an array of arrays of positions (MultiLineString, Polygon) or an array of arrays of arrays of positions (MultiPolygon). The positions within a single object should all have the same number of axes and be in the same axis order.
bbox
Optional, defining a bounding box that the position(s) are contained by.
The box is defined by a array of 2*n items, where n is the number of dimensions in a position. The items are the lowest value for an axis followed by the highest value for an axis, in the axis order used in the positions.
The Co-ordinates Reference System for the bounding box is assumed to match that of the object.
crs
Optional, defining the Co-ordinates Reference System the object is using. See Geo::JSON::CRS for more details.
Geo::JSON::Point
A single position
Geo::JSON::MultiPoint
An array of positions, representing multiple points
Geo::JSON::LineString
An array of 2 or more positions, represening a connected line
Geo::JSON::MultiLineString
An array of lines
Geo::JSON::Polygon
An array of lines, defining a polygon. The first line represents the outside of the polygon, subsequent lines define any 'holes'. The lines must be 'linear rings' - 4 or more points, with the first and last points being equivalent.
Geo::JSON::MultiPolygon
An array of polygons
Geo::JSON::GeometryCollection
An array of any of the above Geometry objects (as attribute geometries)
geometries
Geo::JSON::Feature
Any of the above objects (as attribute feature), together with a data structure (as attruibute properties)
feature
properties
Geo::JSON::FeatureCollection
An array of Feature objects (as attribute features)
features
my $obj = Geo::JSON->from_json( $json );
Takes a geojson string, returns the object it represents.
$obj->to_json(); $obj->to_json( $codec );
Call on a Geo::JSON object. Returns the JSON that represents the object.
Pass in an optional JSON codec to modify the default behaviour of the JSON returned.
my $obj = Geo::JSON->load( { type => 'Point', coordinates => ... } );
Creates a Geo::JSON object from a hashref.
This is used for coercion of attributes during object creation, and probably should not be called directly otherwise.
Geo::JSON->codec->canonical(1)->pretty; my $prev_codec = Geo::JSON->codec($new_codec);
Set options on or replace JSON codec.
Tim Bunce - for codec suggestions and bug spotting.
Geo::JSON::Simple - simple interface to create Geo::JSON objects.
Please report any bugs or feature requests through the issue tracker at https://github.com/mjemmeson/Geo-JSON/issues. You will be notified automatically of any progress on your issue.
This is open source software. The code repository is available for public review and contribution under the terms of the license.
https://github.com/mjemmeson/Geo-JSON
git clone https://github.com/mjemmeson/Geo-JSON.git
Michael Jemmeson <mjemmeson@cpan.org>
This software is copyright (c) 2015 by Michael Jemmeson <mjemmeson@cpan.org>.
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.
To install Geo::JSON, copy and paste the appropriate command in to your terminal.
cpanm
cpanm Geo::JSON
CPAN shell
perl -MCPAN -e shell install Geo::JSON
For more information on module installation, please visit the detailed CPAN module installation guide.