If you would like to authorize one Google Drive account for all your Salesforce users to use when generating documents, have the one selected Admin profile user follow these steps:

  1. Go to your Setup > Developer > Visualforce Page > Click on ‘Administration’ page.
  2. Click on “Preview” custom button on top right.
  3. From there, VisualForce page will come up and there will be two separate tab options on left:
    one for Drive authorization and one for Batch Mode (see this article fore more detail on Batch Mode).
  4. Click on “Authorization” tab. The authorization section contains:
    1. One checkbox to define that one user can authorize on behalf of all other users
    2. Picklist with a list of users to choose from in Salesforce to authorize drive for all other users
    3. One checkbox to force this authorization for all users
  5. You will want to check both of these check boxes and then select your service user from the drop down list. See example screenshot with my example saying “Travis Ramsey” and yours will say “service account” or whatever the name of that user is.
  6. Click to save settings
  7. After above steps done, go to RS Documents Configuration tab to authorize the google drive you would like to use for ALL your Salesforce users.
  8. After above steps are complete, test successful document generation under same user.
  9. After document is generated successfully then you can test this org wide feature by logging in as a different user (different than the user that you configured under Administration page) and test to generate document. This user should be able to also successfully generate document with no authorization error and the generated document will go to the same Google Drive as the admin user specified.

If you need to revoke access and/or delete previous authorizations: 

  1. If you checked the box to ‘force authorization for all users,’ under Administration Visualforce page as outlined above in step #4, then this will override the previous authorizations.
  2. If you did not check this box or do not want to force authorization for ALL users, then you have option to individually revoke the google drive authorization token under each user:
    1. For each user that you want to revoke access, have their user go to RS Documents Configuration tab and then click ‘Revoke Access’ button. Once they do this step, they will now generate documents to the same drive as the admin user specified as long as they had checked box  to define that ‘one user can authorize on behalf of all other users’ under Administration VisualForce page.
    2. If this user or any other user still wants to authorize a separate google drive from the one admin specified, they can go back to RS Document Configuration tab to click “grant access” and this will override the admin setting/drive (as long as the box was not checked under admin to ‘force this authorization for all users’).