GAS で、Google Spreadsheet の内容を 辞書のリストで取得する

function myFunction() {
  var data = getDataOfSheetId('xxxxx-xxxxxxxxxxxxxxxxxxxx_xxxxxx', 0);
  console.log(data);
}

function getDataOfSheetId(spreadsheetId, sheetIndex) {
  var book = SpreadsheetApp.openById(spreadsheetId);
  var sheet = book.getSheets()[sheetIndex];
  console.log(sheet.getName());
  var [rows, columns] = [sheet.getLastRow(), sheet.getLastColumn()];
  var data = sheet.getRange(1, 1, rows, columns).getValues();
  var header = data[0];
  data.shift();
  return data.map(function(row) {
    return header.reduce(function(o, h, i) {
      o[h] = row[i];
      return o;
    }, {});
  });
}

参考:

javascript - How to get data from google sheets as an array of dictionary - Stack Overflow