getMails.gs

function getMails() {
  var sheetId = ''; // use your Sheets ID here
  var ss = SpreadsheetApp.openById(sheetId); 
  
  var s = ss.getSheetByName('logger');
  var threads = GmailApp.search('-in:trash');
  var a=[];
  for (var i = 0; i < threads.length; i++) {
    var messages = GmailApp.getMessagesForThread(threads[i]);
    for (var j = 0; j < messages.length; j++) {
      a[j]= [messages[j].getDate(), messages[j].getFrom(), messages[j].getSubject(), messages[j].getPlainBody()];
    }
  }
  Logger.log(a);
  var nextRow=s.getLastRow() + 1;
  Logger.log("Next Row to write: " + nextRow);
  var numRows=a.length;
  Logger.log("Number of mails fetched: " + numRows);
  if (numRows > 0) {
    var numCols=a[0].length;
    Logger.log("Number of rows per mail: " + numCols);
    s.getRange(nextRow,1,numRows,numCols).setValues(a);
    GmailApp.moveThreadsToTrash(threads);
  }
}