Code-03.gs

// FILTERING EMAILS...

function getBankEmails() {
  // This function searches for messages from emails having subject containing
  // “GeNS transaction Alert …”
  var filter =  "subject:GeNS transaction Alert";
  var threads = GmailApp.search(filter, 0, 10);
  var messages = [];

  for (var x in threads) {
    var thread = threads[x]
    messages.push(thread.getMessages()[0]);
  }
  return messages;
}

function displayEmails() {
  var templ = HtmlService.createTemplateFromFile('messages');
  templ.messages = getBankEmails();
  return templ.evaluate();
}