Allow attributes of whitelist tags start with data-


var source = '<div a="1" b="2" data-a="3" data-b="4">hello</div>';
var html = xss(source, {
  onIgnoreTagAttr: function (tag, name, value, isWhiteAttr) {
    if (name.substr(0, 5) === 'data-') {
      // escape its value using built-in escapeAttrValue function
      return name + '="' + xss.escapeAttrValue(value) + '"';
    }
  }
});

console.log('%s\nconvert to:\n%s', source, html);

Result:

<div a="1" b="2" data-a="3" data-b="4">hello</div>
convert to:
<div data-a="3" data-b="4">hello</div>