Force ask authorization onOpen() (force popup)

SUMMARY: Is it possible to ask for authorization onOpen()?

DETAILED VERSION: I have a spreadsheet with buttons that gets distributed to a lot of people. When any button is pressed, some functions that require permissions are called, so Google Apps Script shows this popup:

AFTER this is accepted, everything runs well, since it has authorization now. However, I want to run things that require permissions BEFORE a button is pushed, when the Workbook is opened. However, if you place authorization-requiring code into an onEdit or onOpen function, it runs with no privileges by default and crashes halfway, rather than showing the popup and asking for permissions.

Here is some code that exemplifies this - crashing instead of asking for permissions to create a trigger (also works for CalendarApp, etc.):

function onOpen(e) {
  Browser.msgBox("This is shown to the user");
  try {
    ScriptApp.newTrigger('someFunction').forSpreadsheet(SpreadsheetApp.getActiveSpreadsheet()).onEdit().create();
  }
  catch (e) {
    Browser.msgBox(e);
  }
  Browser.msgBox("This message is never shown to the user if there is no try catch because it crashes");
}

Note: A simple trigger cannot access services that require authorization. For example, a simple trigger cannot send an email because the Gmail service requires authorization

onOpen() is a reserved function name for a function that is a simple trigger.

There is a way to check the authorization status, and then get the authorization URL if the code needs to be authorized. However, if the ScriptApp.getAuthorizationInfo(ScriptApp.AuthMode.FULL) method needs authorization by the user, then it won't work when run from onOpen()

The onOpen method can not open a sidebar, so the authorization status can't be checked from the onOpen trigger. The user would need to click a menu item that opened the sidebar or a dialog box first.

I'm not sure that the code 'ScriptApp.getAuthorizationInfo(ScriptApp.AuthMode.FULL)` works that well. To force a re-authorization prompt, you may need to run code that would cause the scopes to be evaluated.

Code.gs

function onOpen() {
  //Create custom menu or add-on menu
}

function showSidebar() {
  var html = HtmlService.createTemplateFromFile('HTML_Sidebar').evaluate()
      .setTitle('Log Tools')
      .setWidth(300);
  SpreadsheetApp.getUi() 
      .showSidebar(html);
}

HTML_Sidebar

<!DOCTYPE html>
<html>
  <head>
    <base target="_blank">
  </head>
  <body>

    <div><?!= getAuthUrl(); ?></div>
  </body>

</html>

GS_Sidebar

function getAuthUrl() {
  var authInfo,msg;

  authInfo = ScriptApp.getAuthorizationInfo(ScriptApp.AuthMode.FULL);

  msg = 'This spreadsheet needs permission to use Apps Script Services.  Click ' +
    'this url to authorize: <br><br>' + 
      '<a href="' + authInfo.getAuthorizationUrl() +
      '">Link to Authorization Dialog</a>' +      
      '<br><br> This spreadsheet needs to either ' +
      'be authorized or re-authorized.';

  //return msg;//Use this for testing

  //ScriptApp.AuthMode.FULL is the auth mode to check for since no other authorization mode requires
  //that users grant authorization
  if (authInfo.getAuthorizationStatus() === ScriptApp.AuthorizationStatus.REQUIRED) {
    return msg;
  } else {
    return "No Authorization needed";
  }
}

Nowadays it's not always possible to force ask authorization onOpen as Google made some policy changes that now prevent that script automatically open an UI element by using a simple trigger like onOpen.

This could be possible for the owner of the spreadsheet but not for editors.

From my answer (almost one year old, 0 votes so far) to onOpen not executing?

A simple trigger open function can't open a sidebar because it runs on AuthMode.LIMITED. You should use a function that runs on Auth.Mode.FULL to open a sidebar, like an installable trigger.

I know that this isn't about add-ons but the following quote applies

From https://developers.google.com/apps-script/add-ons/lifecycle#authorization_modes

Note: Add-ons can't open sidebars or dialogs while executing in AuthMode.LIMITED. You can use menu items to open sidebars and dialogs since these run in AuthMode.FULL.

The cannonical references are

https://developers.google.com/apps-script/guides/triggers/

https://developers.google.com/apps-script/guides/triggers/events

来源：https://stackoverflow.com/questions/44892964/force-ask-authorization-onopen-force-popup

标签

google-apps-script

permissions

google-sheets

authorization