11 Feb 2024 (Sun)

09:15:01 # Life Adding a new date entry using GAS on Google Docs. When I am writing a diary, or having a weekly meeting, it is sometimes tedious to add today's date every time. I can automate such tasks with GAS. There's a onOpen method that gets called every time a doc is opened, and you can use that to implement adding the latest date when the latest date does not match.

/**
 * @OnlyCurrentDoc
 */

function onOpen(e) {
  DocumentApp.getUi().createAddonMenu()
      .addItem('Add today', 'addToday')
      .addToUi();

  addToday();
}

/**
 * Add today's date string to top of the document.
 */
function addToday() {
  if (!LockService.getDocumentLock().tryLock(10000)) {
    Logger.log("Could not get lock");
    return;
  }

  var body = DocumentApp.getActiveDocument().getBody();
  var paragraphs = body.getParagraphs();
  var firstParagraph = paragraphs[0].getText();
  var d = new Date();
  var todayDate = d.getFullYear() + '-' + (d.getMonth() + 1) + '-' + d.getDate();
  Logger.log('today is %s and your doc says %s', todayDate, firstParagraph);
  if (todayDate != firstParagraph) {
    body.insertListItem(0, "").setGlyphType(DocumentApp.GlyphType.BULLET);
    body.insertParagraph(0, todayDate).setHeading(DocumentApp.ParagraphHeading.HEADING1);
    Logger.log('inserted today!');
  }
}