From c66443ab5a5fb2734c30ca5d90297efd64188ce9 Mon Sep 17 00:00:00 2001
From: Patrick Strawderman <patrick@kilink.net>
Date: Mon, 30 Nov 2020 09:54:30 -0800
Subject: [PATCH] DATAES-988 Allow specifying max results in
 NativeSearchQueryBuilder

Original PR: #561

Add a withMaxResults method to NativeSearchQueryBuilder for specifying the maxResults
on the built Query. This is common for aggregation queries where search hits are not
needed.

Having the builder method for setting maxResults is a minor ergonomic improvement, e.g.

NativeSearchQuery searchQuery = NativeSearchQueryBuilder()
        .withQuery(matchAllQuery())
        .addAggregation(terms("examples").field("example"))
        .withMaxResults(0)
        .build();

versus what was required before:

NativeSearchQuery searchQuery = NativeSearchQueryBuilder()
        .withQuery(matchAllQuery())
        .addAggregation(terms("examples").field("example"))
        .build();
searchQuery.setMaxResults(0);
---
 .../core/query/NativeSearchQueryBuilder.java          | 11 +++++++++++
 .../ElasticsearchTemplateAggregationTests.java        |  2 ++
 2 files changed, 13 insertions(+)

diff --git a/src/main/java/org/springframework/data/elasticsearch/core/query/NativeSearchQueryBuilder.java b/src/main/java/org/springframework/data/elasticsearch/core/query/NativeSearchQueryBuilder.java
index fa5d9fdf7..c83abd00e 100755
--- a/src/main/java/org/springframework/data/elasticsearch/core/query/NativeSearchQueryBuilder.java
+++ b/src/main/java/org/springframework/data/elasticsearch/core/query/NativeSearchQueryBuilder.java
@@ -66,6 +66,7 @@ public class NativeSearchQueryBuilder {
 	@Nullable private SearchType searchType;
 	@Nullable private IndicesOptions indicesOptions;
 	@Nullable private String preference;
+	@Nullable private Integer maxResults;
 
 	public NativeSearchQueryBuilder withQuery(QueryBuilder queryBuilder) {
 		this.queryBuilder = queryBuilder;
@@ -167,6 +168,11 @@ public class NativeSearchQueryBuilder {
 		return this;
 	}
 
+	public NativeSearchQueryBuilder withMaxResults(Integer maxResults) {
+		this.maxResults = maxResults;
+		return this;
+	}
+
 	public NativeSearchQuery build() {
 
 		NativeSearchQuery nativeSearchQuery = new NativeSearchQuery(queryBuilder, filterBuilder, sortBuilders,
@@ -218,10 +224,15 @@ public class NativeSearchQueryBuilder {
 		if (indicesOptions != null) {
 			nativeSearchQuery.setIndicesOptions(indicesOptions);
 		}
+
 		if (preference != null) {
 			nativeSearchQuery.setPreference(preference);
 		}
 
+		if (maxResults != null) {
+			nativeSearchQuery.setMaxResults(maxResults);
+		}
+
 		return nativeSearchQuery;
 	}
 }
diff --git a/src/test/java/org/springframework/data/elasticsearch/core/aggregation/ElasticsearchTemplateAggregationTests.java b/src/test/java/org/springframework/data/elasticsearch/core/aggregation/ElasticsearchTemplateAggregationTests.java
index a13174cb7..311f476ef 100644
--- a/src/test/java/org/springframework/data/elasticsearch/core/aggregation/ElasticsearchTemplateAggregationTests.java
+++ b/src/test/java/org/springframework/data/elasticsearch/core/aggregation/ElasticsearchTemplateAggregationTests.java
@@ -118,6 +118,7 @@ public class ElasticsearchTemplateAggregationTests {
 				.withQuery(matchAllQuery()) //
 				.withSearchType(SearchType.DEFAULT) //
 				.addAggregation(terms("subjects").field("subject")) //
+				.withMaxResults(0) //
 				.build();
 		// when
 		SearchHits<ArticleEntity> searchHits = operations.search(searchQuery, ArticleEntity.class,
@@ -127,6 +128,7 @@ public class ElasticsearchTemplateAggregationTests {
 		// then
 		assertThat(aggregations).isNotNull();
 		assertThat(aggregations.asMap().get("subjects")).isNotNull();
+		assertThat(searchHits.hasSearchHits()).isFalse();
 	}
 
 	/**