Spring Data ES query by nested object date field - spring

Question

Using Spring Data ES.
I have an index named ship with following definition:
import org.springframework.data.annotation.Id;
import org.springframework.data.elasticsearch.annotations.Document;
import org.springframework.data.elasticsearch.annotations.Field;
import org.springframework.data.elasticsearch.annotations.FieldType;
#Document(indexName = "ship", type = "journey")
public class ShipJourney {
#Id
private String shipId;
#Field(type = FieldType.Nested)
private List<ShipLocation> shipLocation;
//getters and setters
}
ShipLocation is a nested object defined as:
import javax.persistence.Temporal;
import javax.persistence.TemporalType;
import java.time.LocalDateTime;
public class ShipLocation {
private double latitude;
private double longitude;
#Temporal(TemporalType.TIMESTAMP)
private LocalDateTime recordedOnTime;
//setters and getters
}
I want to find a ship location just before or equal to LocalDateTime parameter.
I tried this:
ShipJourney findTopByShipIdAndShipLocationRecordedOnTimeLessThanOrderByShipLocationRecordedOnTimeDesc(
String shipId, LocalDateTime recordedOnTime);
only to realise later that I was using Top on the ShipJourney itself which will be eventually one record only due to the shipId's uniqueness.
How can I limit the data I get for the nested element based on one of its attribute?

Answer 1

I'm not sure if it's possible with the Spring Data ElasticSearch repositories. If you can autowire ElasticSearchTemplate, your query could look something like this (untested):
String shipId = "A";
LocalDateTime recordedOnTime = LocalDateTime.now();
int maxShipLocations = 3; // <-- TOP
NestedQueryBuilder findByLocation = nestedQuery("shipLocation", rangeQuery("shipLocation.recordedOnTime").lt(recordedOnTime));
TermQueryBuilder findById = termQuery("id", shipId);
QueryBuilder findByIdAndLocation = QueryBuilders.boolQuery()
.filter(findById)
.filter(findByLocation.innerHit(new QueryInnerHitBuilder().setSize(maxShipLocations)));
SearchQuery query = new NativeSearchQueryBuilder()
.withIndices("ship")
.withTypes("journey")
.withQuery(findByIdAndLocation)
.withSort(SortBuilders.fieldSort("shipLocation.recordedOnTime").order(SortOrder.DESC))
.build();
List<ShipJourney> shipJourney = elasticSearchTemplate.queryForList(query, ShipJourney.class);