How to define global variable in Google Apps Script
You might be better off using the Properties Service as you can use these as a kind of persistent global variable. click ‘file > project properties > project properties’ to set a key value, or you can use PropertiesService.getScriptProperties().setProperty(‘mykey’, ‘myvalue’); The data can be retrieved with var myvalue = PropertiesService.getScriptProperties().getProperty(‘mykey’);