BBP KML Generator.js

function readRows() {

//  var SPREADSHEET_ID = "";
  var FOLDER_ID = "";
  
  var folder = DriveApp.getFolderById(FOLDER_ID);
  
  moveOldKMLFilesToTrash(folder);
  
  var ss = SpreadsheetApp.getActiveSpreadsheet();

//  var ss = SpreadsheetApp.openById(SPREADSHEET_ID);
  // get the first sheet in the spreasdsheet at index [0]
  var sheet = ss.setActiveSheet(ss.getSheets()[0]);

  // turn every row into a json with the header as the key
  var rowsData = getRowsData(sheet, sheet.getDataRange());

  // find all the unique featureTypes
  var featureTypes = getFeatureTypes(rowsData);
  
  for(var key in featureTypes){
    var featureList = featureTypes[key];
      var kml = createLayerKML(key,featureList);
      saveLayerKML(key,kml);
      Utilities.sleep(500);
  }
}
  
function moveOldKMLFilesToTrash(folder){
  var oldFiles = folder.getFiles();
  while(oldFiles.hasNext()){
      var file = oldFiles.next();
      file.setTrashed(true);
  }
}

function createLayerKML(key,featureList){
  var kmlString = initializeKML(key);
  for(var i = 0; i < featureList.length; i++){  
    kmlString += buildKMLPlacemarkPoint(featureList[i]);
  }
  kmlString += finishKML();
  return kmlString;
}

function saveLayerKML(featureName, kml){
  var FOLDER_ID = "";
  var rootFolder = DriveApp.getRootFolder();
  var folder = DriveApp.getFolderById(FOLDER_ID);
  var xmlFile = DriveApp.createFile(featureName, kml.toString(), MimeType.PLAIN_TEXT);
  folder.addFile(xmlFile);
  rootFolder.removeFile(xmlFile);
}
 
// TODO: Rework to make this function more object oriented and use Xml.parseJS() to stringify
// @david.morris - added support for KML LineStrings on Sunday August 4, 2013
function buildKMLPlacemarkPoint(feature){

  var placemarkString = "";
  
  if (validPlacemark(feature)) {

    placemarkString += "<Placemark>"
                    +  "<name>" + (feature.name ? feature.name : "") + "</name>"
                    +  ((validExtendedData(feature)) ? getExtendedSchema(feature) : "" );

    // handle DataType == "Point"
    // TODO handle bad data with better conditional checks
    if (feature.dataType == "" || feature.dataType == "Point") {    

      placemarkString += "<Point>"
                      +  "<coordinates>" + feature.longitude + "," + feature.latitude + ",0.000000</coordinates>"
                      +  "</Point>";

    } 
    // handle DataType == "Line"
    else if (feature.dataType == "Line") {
      
      placemarkString += "<LineString>"
                      +  "<tessellate>1</tessellate>" // TODO add support for non-tesselation lines?
                      +  "<coordinates>"
                      +  feature.coordinates
                      +  "</coordinates>"
                      +  "</LineString>";

    }
                        
    placemarkString += "</Placemark>";
  }

  return placemarkString ;
}

// 8/7/13 - Maribeth removed unecessary extended schema that had already been removed from the speadsheet (amenities, hours, canToggle, clickable, subtitle)
//          and added if statement to attach customId to line features
function getExtendedSchema(feature){
  var extendedSchema =    "<ExtendedData>"
    +  "<Data name='thumbnail'><value>"   + feature.thumbnail    +"</value></Data>"
    +  "<Data name='image'><value>"       + feature.image        +"</value></Data>"
    +  "<Data name='description'><value>" + feature.description  +"</value></Data>"
    +  "<Data name='url'><value>"         + feature.url          +"</value></Data>"
    +  "<Data name='hasDetail'><value>"   + feature.hasDetail    +"</value></Data>"
    +  "<Data name='folderIcon'><value>"  + feature.folderIcon   +"</value></Data>"
    +  "<Data name='featureIcon'><value>" + feature.featureIcon  +"</value></Data>";
    if (feature.dataType === "Line") {
      extendedSchema +=  "<Data name='customId'><value>" + feature.customId +"</value></Data>";
    }
    extendedSchema += "</ExtendedData>";
  return extendedSchema;
}

function validPlacemark(feature){
  if((feature.approved) && (feature.latitude) && (feature.longitude) && (feature.name) && (feature.approved)){
    return true;
  } else {
    return false;
  }
}

function validExtendedData(feature){
  if((feature.group) && (feature.name)){
    return true;
  } else {
    return false;
  }
}

function initializeKML(name){
  return "<?xml version=\"1.0\" encoding=\"UTF-8\"?><kml xmlns=\"http://www.opengis.net/kml/2.2\">"
           +"<Document>"
             + "<name>" + name + "</name>";
}
function finishKML(){
  return   "</Document>"
         +"</kml>";
}

function getFeatureTypes(features){
var featureTypes ={};
for (var i = 1; i < features.length; i++) {
  var feature = features[i];
  var featureKey = feature.featureType;
  // if the featureType does not exist in the object add it
  if(featureTypes[featureKey] === undefined){
    delete feature.featureType;
    featureTypes[featureKey] = [feature];
  // if the featureType exists
  } else {
    var featureArray = featureTypes[featureKey];
    delete feature.featureType;
    featureArray.push(feature);
  }
};
return featureTypes;
}


////////////////////////
// Example JSON Library from Google App Script documentation
// located @ https://developers.google.com/apps-script/guides/sheets#reading-2
///////////////////////


// getRowsData iterates row by row in the input range and returns an array of objects.
// Each object contains all the data for a given row, indexed by its normalized column name.
// Arguments:
//   - sheet: the sheet object that contains the data to be processed
//   - range: the exact range of cells where the data is stored
//       This argument is optional and it defaults to all the cells except those in the first row
//       or all the cells below columnHeadersRowIndex (if defined).
//   - columnHeadersRowIndex: specifies the row number where the column names are stored.
//       This argument is optional and it defaults to the row immediately above range;
// Returns an Array of objects.

function getRowsData(sheet, range) {
  var headersIndex = 1;
  var dataRange = range ||
    sheet.getRange(headersIndex + 1, 1, sheet.getMaxRows() - headersIndex, sheet.getMaxColumns());
  var numColumns = dataRange.getLastColumn() - dataRange.getColumn() + 1;
  Logger.log(headersIndex + ' ' + dataRange.getColumn() + ' ' + 1 + ' ' + numColumns);
  var headersRange = sheet.getRange(headersIndex, dataRange.getColumn(), 1, numColumns);
  var headers = headersRange.getValues()[0];
  return getObjects(dataRange.getValues(), normalizeHeaders(headers));
}

// For every row of data in data, generates an object that contains the data. Names of
// object fields are defined in keys.
// Arguments:
//   - data: JavaScript 2d array
//   - keys: Array of Strings that define the property names for the objects to create

function getObjects(data, keys) {
  var objects = [];
  for (var i = 0; i < data.length; ++i) {
    var object = {};
    var hasData = false;
    for (var j = 0; j < data[i].length; ++j) {
      var cellData = data[i][j];
      if (isCellEmpty(cellData)) {
        continue;
      }
      object[keys[j]] = cellData;
      hasData = true;
    }
    if (hasData) {
      objects.push(object);
    }
  }
  return objects;
}

// Returns an Array of normalized Strings.
// Arguments:
//   - headers: Array of Strings to normalize
function normalizeHeaders(headers) {
  var keys = [];
  for (var i = 0; i < headers.length; ++i) {
    var key = normalizeHeader(headers[i]);
    if (key.length > 0) {
      keys.push(key);
    }
  }
  return keys;
}


// Normalizes a string, by removing all non-alphanumeric characters and using mixed case
// to separate words. The output will always start with a lower case letter.
// This function is designed to produce JavaScript object property names.
// Arguments:
//   - header: string to normalize
// Examples:
//   "First Name" -> "firstName"
//   "Market Cap (millions) -> "marketCapMillions
//   "1 number at the beginning is ignored" -> "numberAtTheBeginningIsIgnored"

function normalizeHeader(header) {
  var key = "";
  var upperCase = false;
  for (var i = 0; i < header.length; ++i) {
    var letter = header[i];
    if (letter == " " && key.length > 0) {
      upperCase = true;
      continue;
    }
    if (!isAlnum(letter)) {
      continue;
    }
    if (key.length == 0 && isDigit(letter)) {
      continue; // first character must be a letter
    }
    if (upperCase) {
      upperCase = false;
      key += letter.toUpperCase();
    } else {
      key += letter.toLowerCase();
    }
  }
  return key;
}

// Returns true if the cell where cellData was read from is empty.
// Arguments:
//   - cellData: string
function isCellEmpty(cellData) {
  return typeof(cellData) == "string" && cellData == "";
}

// Returns true if the character char is alphabetical, false otherwise.
function isAlnum(char) {
  return char >= 'A' && char <= 'Z' ||
    char >= 'a' && char <= 'z' ||
    isDigit(char);
}

// Returns true if the character char is a digit, false otherwise.
function isDigit(char) {
  return char >= '0' && char <= '9';
}

Found this via Google when trying to get 'getRowsData' to work with getDataRange();

Saved my life. Thanks mate!