How to loop range of cells and set value in adjacent column

Question

I'm learning Google Apps Scripts for use with Google Spreadsheets.

I have a list of URLs in one column and I want to write a script to get the title element from each URL and write it in the adjacent cell. I have accomplished this for one specific cell as per the following script:

function getTitles() {
  var ss = SpreadsheetApp.getActiveSpreadsheet();
  var sheet = ss.getSheetByName("url_list");
  var range = sheet.getRange("G3");
  var url = range.getValue();

  var response = UrlFetchApp.fetch(url);
  var doc = Xml.parse(response.getContentText(),true);
  var title = doc.html.head.title.getText();
  var output = sheet.getRange("H3").setValue(title);

  Logger.log(title);
  return title;
}

This gets the URL in G3, parses it, pulls the element and writes the output in H3.

Now that I have this basic building block I want to loop the entire G column and write the output to the adjacent cell but I'm stuck. Can anyone point me in the right direction?

Answer 1

May look something like this:

function getTitles() {
  var ss = SpreadsheetApp.getActiveSpreadsheet();
  var sheet = ss.getSheetByName("url_list");
  var urls = sheet.getRange("G3:G").getValues();
  var titleList = [], newValues = [],
      response, doc, title;

  for (var row = 0, var len = urls.length; row < len; row++) {
    if (urls[row] != '') {
      response = UrlFetchApp.fetch(urls[row]);
      doc = Xml.parse(response.getContentText(),true);
      title = doc.html.head.title.getText();
      newValues.push([title]);  
      titleList.push(title);  
      Logger.log(title);
    } else newValues.push([]);
  }

  Logger.log('newValues ' + newValues);
  Logger.log('titleList ' + titleList);

  // SET NEW COLUMN VALUES ALL AT ONCE!
  sheet.getRange("H3").offset(0, 0, newValues.length).setValues(newValues);
  return titleList; 
}