node-mapnik

Bindings to Mapnik for node.

Usage

Render a map from a stylesheet:

var mapnik = require('mapnik');
var fs = require('fs');

// register fonts and datasource plugins
mapnik.register_default_fonts();
mapnik.register_default_input_plugins();

var map = new mapnik.Map(256, 256);
map.load('./test/stylesheet.xml', function(err,map) {
    if (err) throw err;
    map.zoomAll();
    var im = new mapnik.Image(256, 256);
    map.render(im, function(err,im) {
      if (err) throw err;
      im.encode('png', function(err,buffer) {
          if (err) throw err;
          fs.writeFile('map.png',buffer, function(err) {
              if (err) throw err;
              console.log('saved map image to map.png');
          });
      });
    });
});

Convert a jpeg image to a png:

var mapnik = require('mapnik');
new mapnik.Image.open('input.jpg').save('output.png');

Convert a shapefile to GeoJSON:

var mapnik = require('mapnik');
mapnik.register_datasource(path.join(mapnik.settings.paths.input_plugins,'shape.input'));
var ds = new mapnik.Datasource({type:'shape',file:'test/data/world_merc.shp'});
var featureset = ds.featureset()
var geojson = {
  "type": "FeatureCollection",
  "features": [
  ]
}
var feat = featureset.next();
while (feat) {
    geojson.features.push(JSON.parse(feat.toJSON()));
    feat = featureset.next();
}
fs.writeFileSync("output.geojson",JSON.stringify(geojson,null,2));

For more sample code see the tests and sample code.

Depends

Node v0.10.x or v0.8.x

Installing

By default, binaries when installing node-mapnik >= 1.4.2 and:

64 bit OS X and 64 bit Linux
Node v0.8.x and v0.10.x

On those platforms no external dependencies are needed.

Just do:

npm install mapnik@1.x

However other platforms will fall back to a source compile: see Source Build for details.

Note: This will install the latest node-mapnik 1.x series, which is recommended. There is also an older 0.7.x series which is not recommended to use unless you need to support Mapnik 2.1 or older (e.g. for CartoDB). The 0.7.x series does not provide binaries so you need to follow the Source Build.

Source Build

To build from source you need:

Mapnik >= v2.2.x
Protobuf >= 2.3.0 (protoc and libprotobuf-lite)

To build with OS X Mavericks you need to ensure the bindings link to libc++. An easy way to do this is to set:

export CXXFLAGS=-mmacosx-version-min=10.9

Install Mapnik using the instructions at: https://github.com/mapnik/mapnik/wiki/Mapnik-Installation

Confirm that the mapnik-config program is available and on your $PATH.

Then run:

npm install mapnik --build-from-source

Using node-mapnik from your node app

To require node-mapnik as a dependency of another package put in your package.json:

"dependencies"  : { "mapnik":"*" } // replace * with a given semver version string

Tests

To run the tests do:

npm test

License

BSD, see LICENSE.txt

kkoopa / node-mapnik