Export styles in any format

  require([
    "esri/map", 
    "esri/layers/FeatureLayer", 
    "esri/renderers/SimpleRenderer", 
    "dojo/domReady!"
  ], 
  var map = new Map("esri-map", {
    center: [-60, 38.5],
    zoom: 3,
    basemap: "dark-gray",
    smartNavigation: false
  });

  map.on('load', function() {
    map.disableScrollWheelZoom();
  });

  var layer = new FeatureLayer('http://tmservices1.esri.com/arcgis/rest/services/LiveFeeds/NOAA_METAR_current_wind_speed_direction/MapServer/0', {
    mode: FeatureLayer.MODE_ONDEMAND,
    outFields: ['*']
  });

  map.addLayer(layer);

  layer.on('load', function() {
    console.log('layer', layer.renderer);
    var simpleJson = {
      "type": "simple",
      "label": "",
      "description": "",
      "symbol": {
        "color": [221,52,152,191],
        "size": 3,
        "angle": 0,
        "xoffset": 0,
        "yoffset": 0,
        "type": "esriSMS",
        "style": "esriSMSCircle",
        "outline": {
          "color": [255,255,255,255],
          "width": 0.2,
          "type": "esriSLS",
          "style": "esriSLSSolid"
        }
      }
    }
    var rend = new SimpleRenderer(simpleJson);
    layer.setRenderer(rend);
    
    var malette = new Malette('esri-map', {
      style: simpleJson,
      formatIn: 'esri-json',
      formatOut: 'esri-json',
      exportStyle: true
    });

    malette.on('style-change', function( style ){
      console.log('exported style', style);

      var rend = new SimpleRenderer(style);
      layer.setRenderer(rend);
      layer.redraw();

    });

  });

});