Description
Here we listen to subscribers callbacks and put them into the reach data groups. Such users then will be considered as active during a reac extraction process. Also message responses are being registered here to signalize a successful message delivery which is a required condition in order to create a sent snapshot.
Each registered channel is a signal that we had a successful message delivery for a particular channel so we can calculate the estimation of users that should have received messages and compare them with the actual callback data. This process will be done separately by a reach-extraction service.