Listen to new data in Firebase

Question

When using JAVA SDK for Firebase, we can listen to data changes using ChildEventListener when CHILD_ADDED, CHILD_CHANGED, CHILD_REMOVED or CHILD_MOVED.

As per document, when listener starts, it first raises CHILD_ADDED event for all existing children under the reference node. After that, a new event is raised for every new child.

I don't want to receive get event for any existing nodes but would like to get an event when a new child is added from the time listener starts.

Is there a way in Firebase SDK to not to trigger events for existing nodes?

https://firebase.google.com/docs/database/admin/retrieve-data#child-added

Answer 1

SDKs don't support it. But you can do this in the cloud using Cloud Functions for Firebase:

https://firebase.google.com/docs/functions/database-events https://firebase.google.com/docs/reference/functions/functions.database.RefBuilder#onCreate