FR: Add support for fetching topic subscriptions

[vpavic]

Currently, FirebaseMessaging (and InstanceIdClient that it delegates to) provides support for subscribing to the topic and unsubscribing. However, to be able to fully (and reliably) manage topics from the server, these should be complemented with the ability to fetch the list of current topic subscriptions from the Firebase.

Apparently, the Instance ID API (i.e. iid.googleapis.com/iid) provides this capability - see https://developers.google.com/instance-id/reference/server#get_information_about_app_instances.

It would be nice if the SDK would expose this operation on the InstanceIdClient, and subsequently, FirebaseMessaging.

[vpavic]

Hey @hiranya911 & @chong-shao, do you maybe have a rough idea when this feature would be available? Would a PR help speed this up a bit maybe?

[hiranya911]

This is something that should be scoped out and decided by the product (FCM) team. So I'll let @chong-shao and his team to chime in here.

[chong-shao]

Apologies for the delays on the launch of this API. The team is still working on this, please expect to hear more on this later this year.

I'll keep this thread open to update any progress.

[mslatinac]

Hi, are there any updates regarding the request?

[TimFowle]

Hello
Are there any updates on this?
I was making calls to https://iid.googleapis.com/iid directly but this doesnt appear to support OAuth for newer projects that dont have a Legacy API Key.

Thanks

[vpavic]

@chong-shao, sorry to tag you directly, but are there updates here?

Now that Batch send API is getting decommissioned, using topics (if I'm not mistaken) is the only way to send a message to multiple recipients in a single API call. That means we'll probably explore migrating some of our FCM workloads that were relying on Batch send API to topic - which brings us back to concerns expressed in the description of this issue.

[SylvainAssemat]

Hi all

Same need as @vpavic .
It seems to be a long time there is no evolutions about this feature which seems to be a mandatory feature.
Can you help us to have more facilities on topics ? For example, listing all tokens from a topics, CRUD on topics etc etc...