I plan to generate Facebook events (Conversion API) on server side when the user completes registration process. These events will be used for advertising my solution in Facebook and tuning target audience on registration events.
I use POST request to https://graph.facebook.com/v9.0/289777498957502/events to send events. I have to pass user_data entity inside a body of this request. This user data can be email address, click id, user IP address or something else.
I don't have any of these on server side but I can get it.
The problem is that I don't understand why Facebook needs user data and what exactly it needs as data. I can send everything to Facebook but I need to understand mandatory information it requires.
Do you know what should be sent as user data?
As an option I can send internal ID in my system of each user inside user data but I'm not sure Facebook will be happy with that.
Facebook manuals are a pure joke. Literally all are outdated and no information on user data content and why it's required.