function get_ga(){
  var start_date='2019-04-01';
  var end_date='2019-04-15';
  var ss = SpreadsheetApp.getActiveSpreadsheet();
  var sheet = ss.getSheetByName("Sheet1");

  var request = {
    "reportRequests":
  [
  {
    "viewId": '26676016',
    "dateRanges": [{"startDate": start_date, "endDate": end_date}],
    "metrics": [{"expression": "ga:transactionRevenue"},
    {"expression":"ga:transactions"},{"expression":"ga:sessions"}],
    "dimensions" : [{"name": "ga:sourceMedium"},{"name":"ga:campaign"}]
    }
   ],
   "useResourceQuotas": true,
  }
  var response =
  AnalyticsReporting.Reports.batchGet(JSON.stringify(request));