Unable to use DriveApp.getFileById(id).getLastUpdated(); - google-apps-script

Question

I want to know the latest updated date of a file at location "https://drive.google.com/open?id=XYZ". This address is present in A1 cell of my sheet.
But every time it throws this error: "You do not have permission to call DriveApp.getFileById. Required permissions: (https://www.googleapis.com/auth/drive.readonly || https://www.googleapis.com/auth/drive) (line 3)."
I have made changes in appScript.jason file also.
This is the code that I have written in script editor and call from B1 cell:
function useThis(url){
var id = getIdFromUrl(url);
return DriveApp.getFileById(id).getLastUpdated();
}
function getIdFromUrl(url) {
return url.match(/[-\w]{25,}/);
}
Also, my appscript.json looks like this:
{
"timeZone": "Asia/Kolkata",
"dependencies": {
},
"exceptionLogging": "STACKDRIVER",
"oauthScopes": [
"https://www.googleapis.com/auth/spreadsheets.readonly",
"https://www.googleapis.com/auth/userinfo.email"
]
}
Is there a way I can resolve this. Or any other easier way to get last updated date of a file in google drive?

Answer 1

Custom functions are not applicable to your use case as they can only call services that do not require access to personal data. See GAS documentation on custom functions
If your custom function throws the error message You do not have
permission to call X service., the service requires user authorization
and thus cannot be used in a custom function.