There is sufficient documentation on how the Marketplace API can resolve, activate, list,etc subscriptions (here for instance).
However, now that I'm forming an understanding of how that works, I would like to know the best approach for SharePoint to check wether a user has a license. (in my case checking the tenant id would be sufficient)
I thought I would be able make an api call to the marketplace with a little data packet containing the tenant Id and the user data and it would be able to tell me if there is an active subscription or not. But it doesn't seem to be there... Am I just missing it?
And if this is not these, what is the approach to get subscription data? I could imagine setting up table storage with an azure function to retrieve tenant/user subscription data but it seems that would just be a shadow copy of the marketplace administration.