Leaflet-headless

Leaflet for node.

• Has Leaflet 1.1.x as dependency.
• Uses jsdom to fake ad DOM.
• Uses Image implementation and canvas from canvas. Note that node-canvas needs some dependencies to be installed: for ubuntu: sudo apt-get install libcairo2-dev libjpeg8-dev libpango1.0-dev libgif-dev build-essential g++
• Tiles, Markers and vector layers work well with leaflet-image
• It's slow (~4s for the examples/choropleth/ on my machine).

Example

Run npm install leaflet-headless to install the package. Requiring leaflet-headless will introduce a global L which just works like in the browser.

For vector layers, make sure to use the canvas renderer if you want to use leaflet-image:

var L = require('leaflet-headless');

var map = L.map(document.createElement('div')).setView([52, 4], 10);

var marker = L.marker([52, 4]).addTo(map);

var latlngs = [[52, 4], [54, 4], [54, 6], [52, 6], [52, 4]];
var polyline = L.polyline(latlngs).addTo(map);

Setting map size

Because jsdom does not support clientWidth/clientHeight, leaflet-headless defaults to a map size of 1024x1024px. To adjust this size, use L.Map.setSize(width, height).

map.setSize(800, 600);

Saving images

leaflet-headless adds a convenience function to L.Map to save the current map to an image using leaflet-image.

L.Map.saveImage(filename, callback): Save image to filename and call callback when ready.

map.saveImage('test.png', function (filename) {
    console.log('Saved map image to ' + filename);
});

Other examples:

• examples/leaflet-image/, using leaflet-image to output a .png.
• examples/choropleth/, Choropleth tutorial from leafletjs.com using leaflet-image to output a .png.
• examples/mapbox-geojson, use mapbox.js to render a GeoJSON file with simplestyle styling.

~/leaflet-headless$ npm install
[...]
~/leaflet-headless$ cd examples/leaflet-image/
~/leaflet-headless/examples/leaflet-image/$ node index.js
Save to image using leaflet-image...
Saved test.png

Run tests

npm test

Attribution

This is inspired by https://github.com/rclark/server-side-leaflet.