DATAES-803 - Move count request setup from reactive template to reactive client.

Original PR: spring-projects#439

Author: sothawo

src/main/java/org/springframework/data/elasticsearch/client/reactive/DefaultReactiveElasticsearchClient.java

@@ -386,6 +386,9 @@ public Mono<DeleteResponse> delete(HttpHeaders headers, DeleteRequest deleteRequ
 	 */
 	@Override
 	public Mono<Long> count(HttpHeaders headers, SearchRequest searchRequest) {
+		searchRequest.source().trackTotalHits(true);
+		searchRequest.source().size(0);
+		searchRequest.source().fetchSource(false);
 		return sendRequest(searchRequest, requestCreator.search(), SearchResponse.class, headers) //
 				.map(SearchResponse::getHits) //
 				.map(searchHits -> searchHits.getTotalHits().value) //

src/main/java/org/springframework/data/elasticsearch/core/ReactiveElasticsearchTemplate.java

@@ -643,8 +643,6 @@ private Mono<Long> doCount(Query query, Class<?> entityType, IndexCoordinates in
 
 			SearchRequest request = requestFactory.searchRequest(query, entityType, index);
 			request = prepareSearchRequest(request);
-			request.source().size(0);
-			request.source().trackTotalHits(true);
 			return doCount(request);
 		});
 	}

src/test/java/org/springframework/data/elasticsearch/client/reactive/DefaultReactiveElasticsearchClientTest.java

@@ -0,0 +1,82 @@
+/*
+ * Copyright 2020 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.data.elasticsearch.client.reactive;
+
+import static org.assertj.core.api.Assertions.*;
+import static org.elasticsearch.search.internal.SearchContext.*;
+import static org.mockito.Mockito.*;
+
+import org.elasticsearch.search.fetch.subphase.FetchSourceContext;
+import reactor.core.publisher.Mono;
+
+import java.util.function.Function;
+
+import org.elasticsearch.action.search.SearchRequest;
+import org.elasticsearch.client.Request;
+import org.elasticsearch.index.query.QueryBuilders;
+import org.elasticsearch.search.builder.SearchSourceBuilder;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.ArgumentCaptor;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.springframework.web.reactive.function.client.ClientResponse;
+import reactor.test.StepVerifier;
+
+/**
+ * @author Peter-Josef Meisch
+ */
+@ExtendWith(MockitoExtension.class)
+class DefaultReactiveElasticsearchClientTest {
+
+	@Mock private HostProvider hostProvider;
+
+	@Mock private Function<SearchRequest, Request> searchRequestConverter;
+
+	private DefaultReactiveElasticsearchClient client;
+
+	@BeforeEach
+	void setUp() {
+		client = new DefaultReactiveElasticsearchClient(hostProvider, new RequestCreator() {
+			@Override
+			public Function<SearchRequest, Request> search() {
+				return searchRequestConverter;
+			}
+		}) {
+			@Override
+			public Mono<ClientResponse> execute(ReactiveElasticsearchClientCallback callback) {
+				return Mono.empty();
+			}
+		};
+	}
+
+	@Test
+	void shouldSetAppropriateRequestParametersOnCount() {
+
+		SearchRequest searchRequest = new SearchRequest("someindex") //
+				.source(new SearchSourceBuilder().query(QueryBuilders.matchAllQuery()));
+
+		client.count(searchRequest).as(StepVerifier::create).verifyComplete();
+
+		ArgumentCaptor<SearchRequest> captor = ArgumentCaptor.forClass(SearchRequest.class);
+		verify(searchRequestConverter).apply(captor.capture());
+		SearchSourceBuilder source = captor.getValue().source();
+		assertThat(source.size()).isEqualTo(0);
+		assertThat(source.trackTotalHitsUpTo()).isEqualTo(TRACK_TOTAL_HITS_ACCURATE);
+		assertThat(source.fetchSource()).isEqualTo(FetchSourceContext.DO_NOT_FETCH_SOURCE);
+	}
+}