Register app-only access with REST API

Question

Is there any way to reproduce the app-only access registration using REST process described here: https://docs.microsoft.com/en-us/sharepoint/dev/solution-guidance/security-apponly-azureacs

More precise, I need the 2nd step automated that goes via: /_layouts/15/appinv.aspx

Use case: I have a SharePoint provisioning process in Power Automate, combined with an Azure Powershell script that applies a PnP template. This script is using azure credentials that connect with legacy authentication. Our security team instructed us to leave legacy authentication behind. We don't want to create a tenant-wide scope app.

My plan is:

• Run the provisioning process as normal
• Grant the app access to the site collection using REST as last step
• Apply the template using the app credentials

Tried to search, but all results was how to use the app-only access to do things with the api, and not how to grant app-only access with api.

Alernatives are also welcome, as long as they work without tenant-level actions.

Answer 1

No, it is manual-only by design. It's a consent screen.