onDocumentWritten method
Event handler that triggers when a document is created, updated, or deleted in Firestore.
@param documentOrOpts - Options or a string document path. @param handler - Event handler which is run every time a Firestore create, update, or delete occurs.
Implementation
external JSFunction onDocumentWritten(
JSAny documentOrOpts,
// (FirestoreEvent<DocumentSnapshot> event) => FutureOr<void>
JSFunction handler,
);