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node-mapnik

Bindings to Mapnik for node.

Usage

Render a map from a stylesheet:

const fs = require('node:fs');
const mapnik = require('@mapnik/mapnik');

// 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/mapnik');
new mapnik.Image.open('input.jpg').save('output.png');

Convert a shapefile to GeoJSON:

const fs = require('node:fs');
const path = require('node:path');
const mapnik = require('@mapnik/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.

Requirements

Starting from v4.6.0, node-mapnik module is published as "universal" binaries on GitHub NPM registry using node-addon-api, node-gyp-build and prebuildify

Currently supported platforms are

  • linux-x64
  • linux-arm64 (from v4.6.5)
  • darwin-x64
  • darwin-arm64

Consult N-API documentation for more details: https://nodejs.org/dist/latest/docs/api/n-api.html#n_api_node_api_version_matrix

Installing

With npm

Consult "Installing a package ". You will need to authenticate to GitHub Packages, see "Authenticating to GitHub Packages."

per-user config file [.npmrc](https://docs.npmjs.com/cli/v10/configuring-npm/npmrc), create a new .npmrc file if one doesn't exist.

edit the .npmrc file to include the following lines, replacing TOKEN with your personal access token.

@mapnik:registry=https://npm.pkg.github.com
//npm.pkg.github.com/:_authToken=XXXXXXXXXXXXXXXXXXXXXXXXX
npm install @mapnik/mapnik

Note: This will install the latest node-mapnik 4.6.x series, which is recommended.

Source Build [WIP]

On macOS and Linux:

  • Ensure mapnik-config program is available and on your ${PATH}.

  • npm install --build-from-source

  • To "prebuild" binaries npm run prebuildify

Note on SSE:

SSE support is enabled by default on x86_64.

Using node-mapnik from your node app

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

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

Tests

To run the tests do:

npm test

License

BSD, see LICENSE.txt