How to optimize fileiterator (to avoid timeout) in Google Scripts - google-apps-script

Question

I am hitting the Google Scripts 6-minute timeout. The script is running through quite a few folders and subfolders. I am hoping that there is either (or both):
A way to optimize the script to more efficiently/intelligently run through the dataset/iterators?
A way to use a getContinuationToken()
Any help would be much appreciated!
I have tried to limit the number of folders/subfolders the script runs through. Even on a 'minimal' run, it times out. And FYI, my goal is to:
make a copy of files that are NOT owned by 'me'...
change the name of the original file (that was not owned by me) to be 'delete'
Here is the code:
FOLDERS = ["0B4FiuEqe8ftGb2lSbjJzakJDNWs"]; /*, "0B4FiuEqe8ftGN2YxZFU5RlhMSDQ", "0B4FiuEqe8ftGN2YxZFU5RlhMSDQ", "1D_1u_KwcLOsBuKyQ7NCsKDd8DB5JwOn6"];*/
function copyNonOwnedFiles() {
var arr = FOLDERS
for (var j = 0; j < arr.length; j++) {
var folderTOP = DriveApp.getFolderById(arr[j]);
var folders = folderTOP.getFolders();
var me = Session.getActiveUser().getEmail();
//RUN #1 = this runs through all of the subfolders
//iterator 1
while (folders.hasNext()) {
var folder = folders.next();
//get all files within these folders
var files = folder.getFiles();
//iterator 2
while (files.hasNext()) {
var file = files.next();
var Owner = file.getOwner().getEmail();
if( Owner !== me ){
var name = file.getName();
file.makeCopy(name);
file.setName('delete');
}
}
}
//RUN #2 = this runs through the parent folder
var files2 = folderTOP.getFiles();
//iterator 2
while (files2.hasNext()) {
var file2 = files2.next();
var Owner = file2.getOwner().getEmail();
if( Owner !== me ){
var name2 = file2.getName();
file2.makeCopy(name2);
file2.setName('delete');
}
}
}
}

Answer 1

Try this:
This script will find the files owned by the active user, in the folders with the listed ids and display them on a modeless dialog. This script will probably need to utilize lock service for multiple simultaneous users.
var myFiles=[];
var ids=["0B4FiuEqe8ftGb2lSbjJzakJDNWs", "0B4FiuEqe8ftGN2YxZFU5RlhMSDQ", "0B4FiuEqe8ftGN2YxZFU5RlhMSDQ", "1D_1u_KwcLOsBuKyQ7NCsKDd8DB5JwOn6"];
var me='';
function getMyFiles() {
myFiles=[];
me=Session.getActiveUser().getEmail();
for(var i=0;i<ids.length;i++) {
getFnF(DriveApp.getFolderById(ids[i]));
}
var html="<style>th,td{border:1px solid black;}</style><table><tr><th>Item</th><th>Name</th><th>Url</th></tr>";
for(var i=0;i<myFiles.length;i++) {
html+=Utilities.formatString('<tr><td>%s</td><td>%s</td><td>Link</td></tr>',i+1,myFiles[i].name,myFiles[i].url);
}
html+='</table><input type="button" value="Close" onClick="google.script.host.close();" />';
var userInterface=HtmlService.createHtmlOutput(html);
var title=Utilities.formatString('Files Owned by: %s',me);
SpreadsheetApp.getUi().showModelessDialog(userInterface, title)
}
function getFnF(folder) {
var folder= folder || DriveApp.getRootFolder();
var files=folder.getFiles();
while(files.hasNext()) {
var file=files.next();
if(file.getOwner().getEmail()==me) {
myFiles.push({name:file.getName(),url:file.getUrl()});
}
}
var subfolders=folder.getFolders()
while(subfolders.hasNext()) {
var subfolder=subfolders.next();
getFnF(subfolder);
}
}

Answer 2

for anyone who has this same question or a similar one... I found that it was much faster/easier/less resource intensive to use a search than a file iterator
dataSheetName = "List";
function onOpen(){
var ui = SpreadsheetApp.getUi();
ui.createMenu('Custom Menu')
.addItem('List Files', 'ListFiles')
.addSeparator()
.addToUi();
}
function ListFiles() {
var sheet = SpreadsheetApp.getActive();
var dataSheet = sheet.getSheetByName(dataSheetName);
// Clear Sheet
var lastRow = dataSheet.getLastRow();
if (lastRow > 0) {
dataSheet.getRange(2, 1, lastRow, dataSheet.getLastColumn()).clearContent();
}
dataSheet.getRange("E2").setValue("Process Started at: " + new Date());
Logger.log("Start: " + new Date());
// var row = ['File Name', 'File Id'];
var row = ['File Name', 'File Id'];
var data = [];
data.push(row);
// Find files modified in the last 24 hours
var totalDays = 30;
var today = new Date();
var oneDayAgo = new Date(today.getTime() - totalDays * 24 * 60 * 60 * 1000);
var startTime = oneDayAgo.toISOString();
// The magic search expression
var search = '(trashed = false) and (modifiedDate > "' + startTime + '") and not (title contains \'DELETE\') and not (\'me\' in owners) ';
// var search = "(mimeType='image/jpeg') and not (title contains 'DELETE') ";
// var search = " not ('me' in owners) and not (title contains 'DELETE') ";
// var search = " not ('me' in owners) ";
//var search = 'sharedWithMe';
// 'me' in owners
var i = 1;
var files = DriveApp.searchFiles(search);
Logger.log("2: " + new Date());
dataSheet.getRange("E3").setValue("Search Completed at: " + new Date());
// while (files.hasNext() && (i < 10000) {
while (files.hasNext() ) {
var file = files.next();
try {
// data.push([file.getName(),file.getId()]);
data.push([file.getName(), file.getId()]);
}
catch (e) {
Logger.log(file.getName());
}
// i += i;
}
// Write data
var dataRange = dataSheet.getRange(1, 1, data.length, row.length);
dataRange.setValues(data);
Logger.log("3: " + new Date());
dataSheet.getRange("E4").setValue("List Completed at: " + new Date());
}