Download some data on DOM as CSV

csv-download.js

var csvDownload = function (payload) {
    var header = '"f1-value", "f2-value", "f3-value", "f4-value"\r\n',
    	link = document.createElement('a'),
    	csv;

	payload.forEach(function(doc) {
		data += '"' + doc.f1 + '",';
		data += '"' + doc.f2 + '",';
		data += '"' + doc.f3 + '",';
		data += '"' + doc.f4 + '"\r\n';
	}
	
	csv = header + data;
  
	link.href = 'data:text/csv;charset=utf-8,' + escape(csv);
	link.target = '_blank';
	link.download =  'download.csv';

	document.body.appendChild(link);
	link.click();
	document.body.removeChild(link);
}