403 error with message "Google Slides API has not been used in project ... before or it is disabled"

Question

I am trying to generate Google Slides from Google Sheets; have used Sheets script with no issues, but when I try to include Google Slides, after authenticating and getting Oauth permissions prompt, I am getting this error that I cannot find any reference for; I have made sure Google Slides API and Drive API are enabled in the Developers Console.

"Request failed for https://slides.googleapis.com/v1/presentations/... returned code 403. Truncated server response: { "error": { "code": 403, "message": "Google Slides API has not been used in project project-id-... before or it is disab... (use muteHttpExceptions option to examine full response) (line 93, file "Code")"

The code failing is as follows, the function that is failing was copied from How to download Google Slides as images?. Client ID and secret are defined, ommitted just for security

// from https://mashe.hawksey.info/2015/10/setting-up-oauth2-access-with-google-apps-script-blogger-api-example/

function getService() {
  // Create a new service with the given name. The name will be used when
  // persisting the authorized token, so ensure it is unique within the
  // scope of the property store.
  return OAuth2.createService('slidesOauth')

      // Set the endpoint URLs, which are the same for all Google services.
      .setAuthorizationBaseUrl('https://accounts.google.com/o/oauth2/auth')
      .setTokenUrl('https://accounts.google.com/o/oauth2/token')


      // Set the client ID and secret, from the Google Developers Console.
      .setClientId(CLIENT_ID)
      .setClientSecret(CLIENT_SECRET)

      // Set the name of the callback function in the script referenced
      // above that should be invoked to complete the OAuth flow.
      .setCallbackFunction('authCallback')

      // Set the property store where authorized tokens should be persisted.
      .setPropertyStore(PropertiesService.getUserProperties())

      // Set the scopes to request (space-separated for Google services).
      // this is blogger read only scope for write access is:
      // https://www.googleapis.com/auth/blogger
      .setScope('https://www.googleapis.com/auth/blogger.readonly')

      // Below are Google-specific OAuth2 parameters.

      // Sets the login hint, which will prevent the account chooser screen
      // from being shown to users logged in with multiple accounts.
      .setParam('login_hint', Session.getActiveUser().getEmail())

      // Requests offline access.
      .setParam('access_type', 'offline')

      // Forces the approval prompt every time. This is useful for testing,
      // but not desirable in a production application.
      .setParam('approval_prompt', 'force');
}

function authCallback(request) {
  var oauthService = getService();
  var isAuthorized = oauthService.handleCallback(request);
  if (isAuthorized) {
    return HtmlService.createHtmlOutput('Success! You can close this tab.');
  } else {
    return HtmlService.createHtmlOutput('Denied. You can close this tab');
  }
}

// from https://stackoverflow.com/questions/31662455/how-to-download-google-slides-as-images/40678925#40678925

function downloadPresentation(id) {
  var slideIds = getSlideIds(id); 

  for (var i = 0, slideId; slideId = slideIds[i]; i++) {
    downloadSlide('Slide ' + (i + 1), id, slideId);
  }
}
function downloadSlide(name, presentationId, slideId) {
  var url = 'https://docs.google.com/presentation/d/' + presentationId +
    '/export/png?id=' + presentationId + '&pageid=' + slideId; 
  var options = {
    headers: {
      Authorization: 'Bearer ' + getService().getAccessToken()
    }
  };
  var response = UrlFetchApp.fetch(url, options); // This is the failing line 93
  var image = response.getAs(MimeType.PNG);
  image.setName(name);
  DriveApp.createFile(image);
}

Answer 1

EDIT: I got this working with this code snippet:

var CLIENT_ID = '...';
var CLIENT_SECRET = '...';
var PRESENTATION_ID = '...';

// from https://mashe.hawksey.info/2015/10/setting-up-oauth2-access-with-google-apps-script-blogger-api-example/

function getService() {
  // Create a new service with the given name. The name will be used when
  // persisting the authorized token, so ensure it is unique within the
  // scope of the property store.
  return OAuth2.createService('slidesOauth')

      // Set the endpoint URLs, which are the same for all Google services.
      .setAuthorizationBaseUrl('https://accounts.google.com/o/oauth2/auth')
      .setTokenUrl('https://accounts.google.com/o/oauth2/token')


      // Set the client ID and secret, from the Google Developers Console.
      .setClientId(CLIENT_ID)
      .setClientSecret(CLIENT_SECRET)

      // Set the name of the callback function in the script referenced
      // above that should be invoked to complete the OAuth flow.
      .setCallbackFunction('authCallback')

      // Set the property store where authorized tokens should be persisted.
      .setPropertyStore(PropertiesService.getUserProperties())

      // Set the scopes to request (space-separated for Google services).
      .setScope('https://www.googleapis.com/auth/drive')

      // Below are Google-specific OAuth2 parameters.

      // Sets the login hint, which will prevent the account chooser screen
      // from being shown to users logged in with multiple accounts.
      .setParam('login_hint', Session.getActiveUser().getEmail())

      // Requests offline access.
      .setParam('access_type', 'offline')

      // Forces the approval prompt every time. This is useful for testing,
      // but not desirable in a production application.
      .setParam('approval_prompt', 'force');
}

function authCallback(request) {
  var oauthService = getService();
  var isAuthorized = oauthService.handleCallback(request);
  if (isAuthorized) {
    return HtmlService.createHtmlOutput('Success! You can close this tab.');
  } else {
    return HtmlService.createHtmlOutput('Denied. You can close this tab');
  }
}

function getSlideIds(presentationId) {
  var url = 'https://slides.googleapis.com/v1/presentations/' + presentationId;
  var options = {
    headers: {
      Authorization: 'Bearer ' + getService().getAccessToken()
    }
  };
  var response = UrlFetchApp.fetch(url, options);

  var slideData = JSON.parse(response);
  return slideData.slides.map(function(slide) {
    return slide.objectId;
  });
}


// from http://stackoverflow.com/questions/31662455/how-to-download-google-slides-as-images/40678925#40678925

function downloadPresentation(id) {
  var slideIds = getSlideIds(id); 

  for (var i = 0, slideId; slideId = slideIds[i]; i++) {
    downloadSlide('Slide ' + (i + 1), id, slideId);
  }
}

function downloadSlide(name, presentationId, slideId) {
  var url = 'https://docs.google.com/presentation/d/' + presentationId +
    '/export/png?id=' + presentationId + '&pageid=' + slideId; 
  var options = {
    headers: {
      Authorization: 'Bearer ' + getService().getAccessToken()
    }
  };
  var response = UrlFetchApp.fetch(url, options); // This is the failing line 93
  var image = response.getAs(MimeType.PNG);
  image.setName(name);
  DriveApp.createFile(image);
}

function start() {
  var service = getService();
  var authorizationUrl = service.getAuthorizationUrl();
  Logger.log('Open the following URL and re-run the script: %s',
      authorizationUrl);

  if (service.hasAccess()) {
    downloadPresentation(PRESENTATION_ID);
  }
}

I'd guess that the client ID and secret don't come from project you think they come from. You can verify this by visiting your project's credentials page and seeing if there's a matching client ID listed under 'OAuth 2.0 client IDs'. The project containing that client ID needs to have the Slides API enabled.

Also note: the /export/png endpoint you're using isnt a documented/supported Google API so it may be renamed or break in the future. If you're interested in an official API for getting rendered PNGs of slides via the Slides API, follow along with this issue on the tracker.

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Previous content:

Your code is also slightly different than the snippet you're copying from. It's using ScriptApp.getOAuthToken() to get the value of the authorization header, but you're calling a different getService().getAccessToken() function. That looks like you're using the apps-script-oauth2 library to generate your OAuth token. If that's the case, confirm that the Slides API is enabled on the Developer console project that generated the clientId and client secret you're passing in to OAuth2.createService, as its not necessarily the same project attached to your script. If switching to ScriptApp.getOAuthToken() is an option for you, that may work as well.

If that doesnt fix your issue, mind providing more of your code? The snippet you've pasted doesn't seem to match the error message, as your code appears to be making a request to docs.google.com, not slides.googleapis.com as mentioned in the error.

Answer 2

Short version of the solution: Thanks to Maurice Codik efforts I got both his code and mine working.

The issue was with the Authorized redirect URIs setup in the OAuth credentials, which had to be setup to

https://script.google.com/macros/d/[ScriptID]/usercallback

Answer 3

This is not a direct answer to the OP question but does directly address the 1st part of their 1st sentence, which is, "I am trying to generate Google Slides from Google Sheets...." This is the exact use case I created a video (and accompanying blog post[s]) for. NOTE: the payload in the post is JSON, but the full example from the video is in Python, so non-Python devs can simply use it as pseudocode.)