How to provide add-in app only tenant administrative permissions in SharePoint Online
When you are developing SharePoint add-ins and want to register them using the ACS model (appregnew.aspx and appinv.aspx), you will need to follow a special process, when an add-in is requesting tenant admin permissions and in app-only mode.
Azure Access Control (ACS), a service of Azure Active Directory (Azure AD), will be retired on November 7, 2018. This retirement does not impact the SharePoint Add-in model, which uses the
https://accounts.accesscontrol.windows.net hostname (which is not impacted by this retirement). For more information, see Impact of Azure Access Control retirement for SharePoint Add-ins.
Steps to provide tenant admin permission for app only add-in:
- Register app id for the add-in under normal site collection in the tenant where add-in will be deployed.
- URL: https://[tenant].sharepoint.com/_layouts/15/appregnew.aspx
- Provide necessary details for the add-in registration and register ID and secret for your add-in
- Move to appinv.aspx page under your tenant admin site
- URL: https://[tenant]-admin.sharepoint.com/_layouts/15/appinv.aspx
- Perform a lookup for the app id registered in previous steps in appinv.aspx page
- Provide needed permissions for your add-in registration
- Perform trust for the updated add-in registration
Notice that this operation has to be completed under the tenant administration site and account used for these operations will need to have tenant administrative permissions. If you are providing lower level permissions for your add-in, you can complete those under normal site collection URLs with lower permissions.