konva/konva-node/demo.js

var fs = require('fs');

// relative path here
// but you will need just require('konva-node');
var Konva = require('./');

// Create stage. Container parameter is not required in NodeJS.
var stage = new Konva.Stage({
  width: 100,
  height: 100
});

var layer = new Konva.Layer();
stage.add(layer);
var rect = new Konva.Rect({
  width: 100,
  height: 100,
  x: 50,
  y: 50,
  fill: 'white'
});
var text = new Konva.Text({
  text: 'Generated inside node js',
  x: 20,
  y: 20,
  fill: 'black'
});
layer.add(rect).add(text);
layer.draw();
stage.setSize({
  width: 200,
  height: 200
});

// check tween works
var tween = new Konva.Tween({
  node: rect,
  duration: 1,
  x: -50
});
tween.play();

// After tween we want to convert stage to dataURL
setTimeout(function() {
  stage.toDataURL({
    callback: function(data) {
      // Then add result to stage
      var img = new Konva.window.Image();
      img.onload = function() {
        var image = new Konva.Image({
          image: img,
          x: 10,
          y: 50
        });
        layer.add(image);
        layer.draw();
        // save stage image as file
        stage.toDataURL({
          callback: function(data) {
            var base64Data = data.replace(/^data:image\/png;base64,/, '');
            fs.writeFile('./out.png', base64Data, 'base64', function(err) {
              err && console.log(err);
              console.log('See out.png');
            });
          }
        });
      };
      img.src = data;
    }
  });
}, 1050);