public void testBulkAddIterable() {
   BulkRequest bulkRequest = Requests.bulkRequest();
   List<ActionRequest<?>> requests = new ArrayList<>();
   requests.add(new IndexRequest("test", "test", "id").source("field", "value"));
   requests.add(new UpdateRequest("test", "test", "id").doc("field", "value"));
   requests.add(new DeleteRequest("test", "test", "id"));
   bulkRequest.add(requests);
   assertThat(bulkRequest.requests().size(), equalTo(3));
   assertThat(bulkRequest.requests().get(0), instanceOf(IndexRequest.class));
   assertThat(bulkRequest.requests().get(1), instanceOf(UpdateRequest.class));
   assertThat(bulkRequest.requests().get(2), instanceOf(DeleteRequest.class));
 }