Sorry if my English is not good.
I'm making a multiplayer game. When user1 finish his turn, a push notification will be sent from user1 to user2. And when user2 finish his turn, a push notification will be sent from user2 to user1.
I use topic to send push notification from user to user. But I want to limit the number of users can send push in a certain topic (match). I mean that only user1 and user2 have the permission to send push notifcation in their match.
Thanks a lot.