ScriptApp.getOAuthToken not getting the right permissions for drive through url fetch app? - google-apps-script

Question

Trying to explore this with a very simple script but I'm getting an insufficient permissions error:
function mini(){
var gdriveId = "1hp8ncIG4Ww7FH8wi7HjJzzzzzzz";
var options = {
method: "GET",
headers: {
'Authorization': 'Bearer ' + ScriptApp.getOAuthToken()
},
}
var url = "https://www.googleapis.com/drive/v2/files/"+gdriveId+"/children";
var response = JSON.parse(UrlFetchApp.fetch( url, options).getContentText());
}
I tried enabling the v2 drive api in the advanced google services dropdown but that didn't work.

Answer 1

I believe your situation and goal as follows.
From gdriveId in your script, I thought that you want to retrieve the folder list in the root folder of gdriveId using the method of "Children: list" in Drive API v2.
You have already enabled Drive API at Advanced Google Services.
For this, how about this answer?
Modification points:
When your script is put to new GAS project and Drive API is enabled at Advanced Google Services, the scopes of the project is only https://www.googleapis.com/auth/script.external_request. The required scope can be automatically detected by the script editor. But, even when Drive API is only enabled, it seems that no scopes are added. I think that the reason of your issue is this.
Under above situation, if you want to retrieve the access token including the required scopes, in order to make the script editor automatically detect the scope of https://www.googleapis.com/auth/drive.readonly, for example, please put // DriveApp.getFiles() to the script as a comment line.
In this case, when you use the methods for other scopes in your script, those scopes can be automatically detected and added by the script editor.
Modified script 1:
When your script is modified, it becomes as follows.
function mini(){
var gdriveId = "1hp8ncIG4Ww7FH8wi7HjJzzzzzzz";
var options = {
method: "GET",
headers: {
'Authorization': 'Bearer ' + ScriptApp.getOAuthToken()
},
}
var url = "https://www.googleapis.com/drive/v2/files/"+gdriveId+"/children";
var response = JSON.parse(UrlFetchApp.fetch( url, options).getContentText());
}
// DriveApp.getFiles() // <--- Added this comment line. By this, the scope of https://www.googleapis.com/auth/drive.readonly is added.
Modified script 2:
When the method of Advanced Google service is used, the scope of https://www.googleapis.com/auth/drive is automatically added. By this, the following script works.
function test() {
var gdriveId = "1hp8ncIG4Ww7FH8wi7HjJzzzzzzz";
var res = Drive.Children.list(gdriveId);
console.log(res)
}
Other pattern:
From June 1, 2020, the files and folders in the shared Drive can be retrieved by Drive service. So you can also use the following script.
function myFunction() {
const getFolderList = (id, folders = []) => {
const f = DriveApp.getFolderById(id);
const fols = f.getFolders();
let temp = [];
while (fols.hasNext()) {
const fol = fols.next();
temp.push({name: fol.getName(), id: fol.getId(), parent: f.getName()});
}
if (temp.length > 0) {
folders.push(temp);
temp.forEach((e) => getFolderList(e.id, folders));
}
return folders.flat();
};
var gdriveId = "###"; // Please set the Drive ID.
const res = getFolderList(gdriveId);
console.log(res);
}
References:
Advanced Google services
Children: list of Drive API v2
Authorization Scopes

Answer 2

If you want to give permission to write with ScriptApp.getOAuthToken(), just add the following code in a commented out form and authorize it at runtime. If you don't do this, you'll only be able to download and browse.
//DriveApp.addFile("test");
Reference URL：https://00m.in/UeeOB