An iOS app I'm developing also has an external website where users can contribute data to the app's CloudKit public database. Using CloudKit JS, I require users to log in with their Apple ID on the website before submitting data that is sent to the public database. I need to capture the user's name and/or email address from their Apple ID info so the contributed data can be tied to a particular person, I can limit how much data each person contributes, etc. It all works great if I log in with my Apple ID, including that the web app captures my name and saves it to the public database.
The problem is that for any other Apple ID I try (a family member's or friend's, or a sandbox one I've created), the web app cannot obtain the user's name or email address, even when they successfully authenticate with their Apple ID. I also can't figure out how to make the web app ask the user for permission for their name or email to be discoverable. On the CloudKit container page where I created the web API token, I checked the box for "Request user discoverability at sign in", but that doesn't make any prompt appear during the login process. Anyone know how to force a prompt to the user to let their info be discoverable?
Thanks!