Online KML to Google Spreadsheet Script - google-apps-script

Question

Would like to use information into spreadsheets from a live Google Map (KML data). The code below handle it, but not as fast as required. It must handle up to 10 layers with about 2000 placemarks, line positions and/or polygon positions in the interesting (parameter "restrict") layer (or all layers). The size of the kml (xml) data is therefore often quite large.
Question 1: How (if possible) can caching and/or some other solution be implemented to handle about 2Mb xml data?
Question 2: How can what improvements be implemented to stream line the code, add flexibility to dynamically handle unknown (in advance) number of columns/rows and lower the execution time?
/**
* Fetch a Google Map and write the data to the spreadsheet (URL and layer).
*
* #param {url} input the URL associated with the Google Map (should contain &forcekml=1).
* #param {restrict} input the Layer name you want to restrict the data to.
* #return a range of data depending on the info in the map
* #customfunction
*/
function IMPORTMAP( url, restrict ) {
/* One key only allow 100k
var cache = CacheService.getPublicCache();
var cached = cache.get( "google-maps-xml" );
var cached = cache.getAll('?'); //Unknown keys in advance that also may change from time to time.
if ( cached != null ) {
return cached;
}*/
var txt = UrlFetchApp.fetch( url ).getContentText();
var sheet = SpreadsheetApp.getActiveSheet();
var width = sheet.getMaxColumns();
var height = sheet.getMaxRows();
var xmlDoc = XmlService.parse( txt );
var root = xmlDoc.getRootElement();
var atom = XmlService.getNamespace( 'http://www.opengis.net/kml/2.2' );
var xml2csv = [[height],[10]];
var labels = [], label = '', counter = 0, o = 0;
var documents = root.getChildren( 'Document', atom );
for( var i = 0; i < documents.length; i++ ) {
var Folders = documents[i].getChildren( 'Folder', atom );
for( var j = 0; j < Folders.length && j <= height; j++ ) {
if( Folders[j].getChild( 'name', atom ).getValue() == restrict ) {
var Placemarks = Folders[j].getChildren( 'Placemark', atom );
for( var k = 0; k < Placemarks.length; k++ ) {
var nodes = Placemarks[k].getChildren();
for( var l = 0; l < nodes.length; l++ ) {
var data = nodes[l].getChildren();
if( data.length > 0 ) {
for( var m = 0; m < data.length && counter <= width; m++ ) {
if( data[m].getAttribute( 'name' ) != null ) {
if( labels[ data[m].getAttribute( 'name' ).getValue().trim() ] == null ) {
labels[ data[m].getAttribute( 'name' ).getValue().trim() ] = counter;
xml2csv[ 0 ][ counter++ ] = data[m].getAttribute( 'name' ).getValue().trim();
}
}
if( data[m].getChild( 'value', atom ) != null ) {
xml2csv[ k + 1 ][ labels[ data[m].getAttribute( 'name' ).getValue().trim() ] ] = data[m].getChild( 'value', atom ).getValue().trim();
} else {
o = labels[ data[m].getName().trim() ];
if( o == null ) {
labels[ data[m].getName().trim() ] = counter;
o = counter;
xml2csv[ 0 ][ counter++ ] = data[m].getName().trim();
}
if( xml2csv[ k + 1 ] == null ) {
xml2csv[ k + 1 ] = new Array( counter );
}
xml2csv[ k + 1 ][ labels[ data[m].getName().trim() ] ] = data[m].getValue().trim();
}
}
} else {
if( label == '' )
label = nodes[l].getName().trim();
o = labels[ nodes[l].getName().trim() ];
if( o == null ) {
labels[ nodes[l].getName().trim() ] = counter;
o = counter;
xml2csv[ 0 ][ counter++ ] = nodes[l].getName().trim();
}
if( xml2csv[ k + 1 ] == null ) {
xml2csv[ k + 1 ] = new Array( counter );
}
xml2csv[ k + 1 ][ o ] = nodes[l].getValue().trim();
}
}
}
}
}
}
//cache.putAll( xml2csv, 1500 ); // cache for 25 minutes
return xml2csv;
}
Please note that code only handle specific kml data in its current form and may not be suitable for a wider audience.