Springdata elasticsearch 5.2 nested aggregation without subAggregation

Elastic Stack Elasticsearch
5

In case it might help someone, my tech lead could help and provided this solution that is indeed working

fun toNativeQuery(): NativeQuery {
            val criteriaQuery = CriteriaQuery(criteria)
            val queryBuilder = NativeQuery.builder().withQuery(criteriaQuery)
            //...
    
            val subAggRoleName =
            AggregationBuilders.terms { it.field("${ActionEntity::actionRoles.name}.${ActionRoleEntity::roleName.name}") }
            // AggregationBuilder.nested does support sub-aggregations,
            // so we need to build it with the Aggregation.Builder()
            val aggNestedActionRolesName =
            Aggregation
                .Builder()
                .nested { it.path(ActionEntity::actionRoles.name) }
                .aggregations(
                    mapOf("roleNames" to subAggRoleName),
                ).build()
            queryBuilder.withAggregation(AGG_ACTION_ROLE, aggNestedActionRolesName)

            //...
            return queryBuilder.build()
}