javascript download geoserver layer as kml file

 var sqlfilter = " CITY='" + city + "' and SDATE>" + sdate + " and SDATE <" + edate;

soMapRoad.downLoadGeoLayer(actionId, kpi, layerTitle, sqlfilter);

 

 function downloadTileGridMap(layerName, styleId, filterQuery) {

        var url = "http://" + geoIP + "/geoserver/wms?service=WMS&version=1.1.0&request=GetMap&LAYERS=FAST:" + layerName + "&STYLES=" + styleId + "&CQL_FILTER=" + filterQuery + "&bbox=109.0,20.0,118.0,26.0&width=768&height=512&srs=EPSG:4326&format=application/vnd.google-earth.kml+xml";

                 

        window.open(url);

    }

    function downLoadGeoLayer(currentActionId, kpi, sqlfilter) {

        $.getJSON("../Action.json",

            function (json) {

                $.each(json,

                    function (infoIndex, info) {

                        var actionId = info["ID"];

                        if (actionId === currentActionId) {

                            var layerName = info["layers"];

                            var styleId = info["style"];

                            var bbox = info['filter'];

                            var filter = sqlfilter;

                            downloadTileGridMap(layerName, styleId, filter, bbox);

                        }

                    });

            });

    }