DATAMONGO-2574 - Polishing.

Fix issue in reactive API and add unit tests.

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/gridfs/GridFsOperations.java

@@ -129,7 +129,7 @@ public interface GridFsOperations extends ResourcePatternResolver {
 	 *
 	 * @param content must not be {@literal null}.
 	 * @param filename must not be {@literal null} or empty.
-	 * @param contentType can be {@literal null}.
+	 * @param contentType can be {@literal null}. If not empty, may override content type within {@literal metadata}.
 	 * @param metadata can be {@literal null}.
 	 * @return the {@link ObjectId} of the {@link com.mongodb.client.gridfs.model.GridFSFile} just created.
 	 */

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/gridfs/ReactiveGridFsOperations.java

@@ -135,7 +135,7 @@ public interface ReactiveGridFsOperations {
 	 *
 	 * @param content must not be {@literal null}.
 	 * @param filename must not be {@literal null} or empty.
-	 * @param contentType can be {@literal null}.
+	 * @param contentType can be {@literal null}. If not empty, may override content type within {@literal metadata}.
 	 * @param metadata can be {@literal null}.
 	 * @return a {@link Mono} emitting the {@link ObjectId} of the {@link com.mongodb.client.gridfs.model.GridFSFile} just
 	 *         created.
@@ -148,12 +148,12 @@ public interface ReactiveGridFsOperations {
 		if (StringUtils.hasText(filename)) {
 			uploadBuilder.filename(filename);
 		}
-		if (StringUtils.hasText(contentType)) {
-			uploadBuilder.contentType(contentType);
-		}
 		if (!ObjectUtils.isEmpty(metadata)) {
 			uploadBuilder.metadata(metadata);
 		}
+		if (StringUtils.hasText(contentType)) {
+			uploadBuilder.contentType(contentType);
+		}
 
 		return store(uploadBuilder.build());
 	}

spring-data-mongodb/src/test/java/org/springframework/data/mongodb/gridfs/GridFsTemplateUnitTests.java

@@ -0,0 +1,79 @@
+/*
+ * 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.mongodb.gridfs;
+
+import static org.assertj.core.api.Assertions.*;
+import static org.mockito.Mockito.*;
+
+import java.io.ByteArrayInputStream;
+import java.io.InputStream;
+
+import org.bson.Document;
+import org.bson.types.ObjectId;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.springframework.data.mongodb.MongoDatabaseFactory;
+import org.springframework.data.mongodb.core.convert.MongoConverter;
+
+/**
+ * @author Christoph Strobl
+ */
+class GridFsTemplateUnitTests {
+
+	private GridFsTemplateStub template;
+
+	@BeforeEach
+	void beforeEach() {
+		template = new GridFsTemplateStub();
+	}
+
+	@Test // DATAMONGO-2574
+	void contentMetadataDoesNotOverrideContentTypeIfSet() {
+
+		template.onStoreReturn(new ObjectId());
+		template.store(new ByteArrayInputStream(new byte[] {}), "filename", "json", new Document("meta", "data"));
+
+		assertThat(template.capturedUpload().getOptions().getContentType()).isEqualTo("json");
+		assertThat(template.capturedUpload().getOptions().getMetadata()).containsEntry("meta", "data");
+	}
+
+	private static class GridFsTemplateStub extends GridFsTemplate {
+
+		private Object onStoreResult;
+		private GridFsObject<?, InputStream> capturedUpload;
+
+		GridFsTemplateStub() {
+			super(mock(MongoDatabaseFactory.class), mock(MongoConverter.class));
+		}
+
+		@Override
+		public <T> T store(GridFsObject<T, InputStream> upload) {
+
+			this.capturedUpload = upload;
+			return (T) onStoreResult;
+		}
+
+		GridFsTemplateStub onStoreReturn(Object result) {
+
+			this.onStoreResult = result;
+			return this;
+		}
+
+		GridFsObject<?, InputStream> capturedUpload() {
+			return capturedUpload;
+		}
+	}
+}

spring-data-mongodb/src/test/java/org/springframework/data/mongodb/gridfs/ReactiveGridFsTemplateUnitTests.java

@@ -0,0 +1,83 @@
+/*
+ * 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.mongodb.gridfs;
+
+import static org.assertj.core.api.Assertions.*;
+import static org.mockito.Mockito.*;
+
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
+
+import java.io.InputStream;
+
+import org.bson.Document;
+import org.bson.types.ObjectId;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.reactivestreams.Publisher;
+import org.springframework.core.io.buffer.DataBuffer;
+import org.springframework.data.mongodb.ReactiveMongoDatabaseFactory;
+import org.springframework.data.mongodb.core.convert.MongoConverter;
+
+/**
+ * @author Christoph Strobl
+ */
+class ReactiveGridFsTemplateUnitTests {
+
+	private ReactiveGridFsTemplateStub template;
+
+	@BeforeEach
+	void beforeEach() {
+		template = new ReactiveGridFsTemplateStub();
+	}
+
+	@Test // DATAMONGO-2574
+	void contentMetadataDoesNotOverrideContentTypeIfSet() {
+
+		template.onStoreReturn(new ObjectId());
+		template.store(Flux.empty(), "filename", "json", new Document("meta", "data"));
+
+		assertThat(template.capturedUpload().getOptions().getContentType()).isEqualTo("json");
+		assertThat(template.capturedUpload().getOptions().getMetadata()).containsEntry("meta", "data");
+	}
+
+	private static class ReactiveGridFsTemplateStub extends ReactiveGridFsTemplate {
+
+		private Object onStoreResult;
+		private GridFsObject<?, Publisher<DataBuffer>> capturedUpload;
+
+		ReactiveGridFsTemplateStub() {
+			super(mock(ReactiveMongoDatabaseFactory.class), mock(MongoConverter.class));
+		}
+
+		@Override
+		public <T> Mono<T> store(GridFsObject<T, Publisher<DataBuffer>> upload) {
+
+			capturedUpload = upload;
+			return Mono.just((T) onStoreResult);
+		}
+
+		ReactiveGridFsTemplateStub onStoreReturn(Object result) {
+
+			this.onStoreResult = result;
+			return this;
+		}
+
+		GridFsObject<?, Publisher<DataBuffer>> capturedUpload() {
+			return capturedUpload;
+		}
+	}
+}