in iceberg-catalog-migrator/api/src/main/java/org/apache/polaris/iceberg/catalog/migrator/api/CatalogMigrator.java [201:209]
protected void getAllNamespacesFromSourceCatalog(Namespace namespace, Set<Namespace> visited) {
if (!visited.add(namespace)) {
return;
}
List<Namespace> children = ((SupportsNamespaces) sourceCatalog()).listNamespaces(namespace);
for (Namespace child : children) {
getAllNamespacesFromSourceCatalog(child, visited);
}
}