Generate a static image of a Jupyter IGV canvas

IGV-static.py

class IgvCanvasToStatic(object):
    def __init__(self):
        self._javascript = """
        // Converts canvas to an image
        function convertCanvasToImage(canvas)
        {
            var image = canvas.toDataURL("image/png");
            return '<img src="' + image + '"/>';
        }

        // Grab all IGV canvas objects
        var ideogram = document.getElementsByClassName('igv-ideogram-canvas');
        var myCanvas = document.getElementsByClassName('igv-content-canvas');

        // Convert each canvas and append to list
        var images = [];
        for (var i = 0; i < myCanvas.length; i++ )
        {
            if (i == 0) {
                images.push(convertCanvasToImage(ideogram[i]));
            }
            images.push(convertCanvasToImage(myCanvas[i]));
        }

        // combine list and output to a python object
        var panel = images.join('');
        IPython.notebook.kernel.execute("panel = '" + panel + "'")
        """

    @classmethod
    def run(self):
        from Ipython.display import Javascript
        return Javascript(self._javascript)