Hi,

on FCM related push, we do, in our client SDK, automatically subscribe a client to an annoymous topic, matching our immutable variant ID.

If users are specifying categories, we do map those into topics as well.

This is the related code in our Android SDK:
https://github.com/aerogear/aerogear-android-push/blob/master/aerogear-android-push/src/main/java/org/jboss/aerogear/android/unifiedpush/fcm/AeroGearFCMPushRegistrar.java#L188-L193

How do people feel about doing that for the alias as well ? 

In the past we did not do it, since topics used to be a more restricted resource. Remember, the first notion of topics (GCM v3, at that time) were even limiting the number of max. subscribers?

However, that changed, and I think it would be nice if we just use the topics for each alias of the app as well. This would speed up the time to deliver the push request to the FCM backend, since the UPS would no longer need to look up the device, a push, regardless how many devices, means one small HTTP to Google, per alias (aka topic)

Any thoughts ? 

NOTE: There is a general limit of topic abuse, but that's on the app instance (see [1]), so our APP Developers need to make sure they don't go crazy w/ a gazillion of categories ;-) 

-Matthias


[1] https://firebase.google.com/docs/cloud-messaging/admin/errors

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