Elastic Search Scroll API Asynchronous execution

Here the example code:

    public class App {    public static void main(String[] args) throws IOException, InterruptedException {        RestHighLevelClient client = new RestHighLevelClient(                RestClient.builder(HttpHost.create("http://localhost:9200")));        client.indices().delete(new DeleteIndexRequest("test"), RequestOptions.DEFAULT);        for (int i = 0; i < 100; i++) {            client.index(new IndexRequest("test", "_doc").source("foo", "bar"), RequestOptions.DEFAULT);        }        client.indices().refresh(new RefreshRequest("test"), RequestOptions.DEFAULT);        SearchRequest searchRequest = new SearchRequest("test").scroll(TimeValue.timeValueSeconds(30L));        SearchResponse searchResponse = client.search(searchRequest, RequestOptions.DEFAULT);        String scrollId = searchResponse.getScrollId();        System.out.println("response = " + searchResponse);        SearchScrollRequest scrollRequest = new SearchScrollRequest(scrollId)                .scroll(TimeValue.timeValueSeconds(30));        //I was missing to wait for the results        final CountDownLatch countDownLatch = new CountDownLatch(1);        client.scrollAsync(scrollRequest, RequestOptions.DEFAULT, new ActionListener<SearchResponse>() {            public void onResponse(SearchResponse searchResponse) {                System.out.println("response async = " + searchResponse);            }            public void onFailure(Exception e) {            }        });        //Here we wait        countDownLatch.await();        //Clear the scroll if we finish before the time to keep it alive. Otherwise it will be clear when the time is reached.            ClearScrollRequest request = new ClearScrollRequest()        request.addScrollId(scrollId);        client.clearScrollAsync(request, new ActionListener<ClearScrollResponse>(){           @Override           public void onResponse(ClearScrollResponse clearScrollResponse) {           }           @Override           public void onFailure(Exception e) {           }         });        client.close();                  }    }

Thanks to David Pilato elastic discussion

summarizations of each hour for the last 7 day

It sounds like you would like to run some aggregations on the data, and not get the raw docs. probably at the first level a date histogram in order to aggregate on intervals of 1hour. inside that date histogram you need an inner aggs to run your aggregations - either metrics/buckets depending on the summarizations needed.

Starting Elasticsearch v6.1 you can use the Composite Aggregation in order to get all the results buckets using paging. from the docs I linked:

the composite aggregation can be used to paginate all buckets from a multi-level aggregation efficiently. This aggregation provides a way to stream all buckets of a specific aggregation similarly to what scroll does for documents.

Unfortunately this option doesn't exist pre v6.1, so either you'll need to upgrade ES to use it, or find another way, like breaking to multiple queries, that together will cover the 7 days requirement.