node-mapnik
Usage
Render a map from a stylesheet:
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:
new mapnik.Image.open('input.jpg').save('output.png');
Convert a shapefile to GeoJSON:
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 and npmjs using node-addon-api,
node-gyp-build and prebuildify
Currently supported platforms are
linux-x64linux-arm64(from v4.6.5)darwin-x64darwin-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
Note: If using GitHub NPM registry consult "Installing a package ". You will need to authenticate to GitHub Packages, see "Authenticating to GitHub Packages."
- Check for config file
.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.
//npm.pkg.github.com/:_authToken=XXXXXXXXXXXXXXXXXXXXXXXXX
Note: This will install the latest node-mapnik 4.6.x series, which is recommended.
Source Build [WIP]
On macOS and Linux:
-
Ensure
mapnik-configprogram 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