How to query S2member from another database?

I want another server (another service I help run) to query s2member to see if someone is a member on my site. In other words: “If is a member, then set a flag in the database to true.” That service is a custom built site, not a WP database. Obviously, I would want this query to be protected, so that not everyone could do it.

Possible?

@indesignsecrets

Checking for user information in s2member from a remote site is possible through the s2Member Pro API for Remote Operations. You would need to be able to pass either the user’s WP username or WP user id from the remote site to s2Member to check and see whether the user existed in s2Member.

It doesn’t look like the Pro API for Remote Operations has an official check_user method, but you could probably work around that by using the modify_user method and simply not modifying anything but instead checking for an error on the specified username or id. Then you would know if the user existed in s2member or not.