//Find the last indexed Contact's ID func findID(s *elastic.Client) (int, error) { termQuery := elastic.NewMatchAllQuery() searchResult, err := s.Search(). Index("contacts"). Query(&termQuery). Fields("_timestamp"). Sort("_timestamp", false). Size(1). Pretty(true). Do() if err != nil { logs.Critical(err) return 0, err } var ID int if searchResult.Hits != nil { for _, hit := range searchResult.Hits.Hits { ID, err = strconv.Atoi(hit.Id) if err != nil { return 0, err } } } else { logs.Debug("No results, ID is 1") return 1, nil } return ID, nil }