Can't count the occurences of the entity with a field of particular value inside a nested property using Spring Data ElasticSearch Repository

Question

I have the Article entity and inside it there is a nested property, let's say Metadata.

I need to count all articles, which have a particular field inside this nested property, let's say indexed, assigned to e.g. 1.

Java Document Snippet:

@Document(indexName = "article", type = "article", useServerConfiguration = true, createIndex = false)
@Setting(settingPath = "/mappings/settings.json")
@Mapping(mappingPath = "/mappings/articles.json")
public class Article {

// getters and setters, empty constructor are omitted for brevity
    @Id
    private String id;

    private Metadata metadata;

// remainder of the body is omitted

}

Metadata.class snippet

public class Metadata {

// getters and setters, empty constructor are omitted for brevity
    private Integer indexed;

// remainder of the body is omitted
}

The query I use to retrieve articles, which satisfy the given criteria and which I put as a value of @org.springframework.data.elasticsearch.annotations.Query on top of the custom method:

{
  "query": {
    "bool": {
      "must": [
        {
          "nested": {
            "path": "metadata",
            "query": {
              "bool": {
                "must": [
                  {
                    "match": {
                      "metadata.indexed": 1
                    }
                  }
                ]
              }
            }
          }
        }
      ]
    }
  }
}

My custom Spring Data ElasticSearch repository snippet with a custom method:

public CustomSpringDataElasticsearchRepository extends ElasticsearchRepository<Article, String> {

    @Query("The query from above")
    Long countByMetadata_Indexed(int value);
}

When I use the repository method shown above , I get java.lang.IllegalArgumentException: Expected 1 but found n results.

Custom Spring Data Elasticsearch Repository method(without @Query) returns 0(version without underscore returns 0 as well) though it should return everything correctly.

How do I get the correct results using Spring Data ElasticSearch Repository? Why does the custom method without @Query doesn't work as well?

UPD: The version of spring-data-elasticsearch used is 3.1.1.RELEASE.

Answer 1

Repository query methods currently(3.2.4.RELEASE) don't support the count by the fields inside nested fields.

As was mentioned previously, @Query annotation doesn't support custom count queries as of the latest version(3.2.4.RELEASE).

In other words, currently, the only way to do this query through Spring Data ElasticSearch is to use ElasticsearchTemplate bean or ElasticsearchOperations bean.

Credit: P.J.Meisch