Hi,
I cannot find the corresponding API here:
https://docs.atlassian.com/atlassian-confluence/REST/latest/
PS The goal is to check if a user is granted with the update restriction on a page.
As far as I have understood, you can use the following REST API call to get a list of restrictions for a specific page
/confluence/rest/api/content/{contentID}/restriction/byOperation
In order to see if the user can edit the page, you need to check if the user is directly allowed or if he belong to any of the groups having the update restriction. Is this correct or there is a smarter way?