is there a way to send a param like user_id to the subscription?

[vuniverseklaus]

I think should be nice to send the user_id when requesting a subscription and receiving it from in app purchase webhook.
Ie.: I am user_id: 1 and requested a subscription to Apple Pay, after success, Apple send the transaction/receipt notification to our api webhook with the param user_id: 1, so it did not require the mobile app to make a success post to the api after received the success subscription result. I think the currently way to identify the user is reading transaction id result from the subscription and sending to api, but the api depends on mobile to send this information.

Using: https://developer.apple.com/documentation/appstoreservernotifications/enabling_app_store_server_notifications