Use DefaultDbRefResolver whenever MongoDatabaseFactory is available

Fixes gh-39405

Author: wilkinsona

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/data/mongo/MongoDataConfiguration.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2022 the original author or authors.
+ * Copyright 2012-2024 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.
@@ -19,6 +19,7 @@
 import java.util.Collections;
 
 import org.springframework.beans.BeanUtils;
+import org.springframework.beans.factory.ObjectProvider;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
 import org.springframework.boot.autoconfigure.domain.EntityScanner;
 import org.springframework.boot.autoconfigure.mongo.MongoProperties;
@@ -27,8 +28,14 @@
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.data.mapping.model.FieldNamingStrategy;
+import org.springframework.data.mongodb.MongoDatabaseFactory;
 import org.springframework.data.mongodb.MongoManagedTypes;
+import org.springframework.data.mongodb.core.convert.DbRefResolver;
+import org.springframework.data.mongodb.core.convert.DefaultDbRefResolver;
+import org.springframework.data.mongodb.core.convert.MappingMongoConverter;
+import org.springframework.data.mongodb.core.convert.MongoConverter;
 import org.springframework.data.mongodb.core.convert.MongoCustomConversions;
+import org.springframework.data.mongodb.core.convert.NoOpDbRefResolver;
 import org.springframework.data.mongodb.core.mapping.Document;
 import org.springframework.data.mongodb.core.mapping.MongoMappingContext;
 
@@ -70,4 +77,16 @@ MongoCustomConversions mongoCustomConversions() {
 		return new MongoCustomConversions(Collections.emptyList());
 	}
 
+	@Bean
+	@ConditionalOnMissingBean(MongoConverter.class)
+	MappingMongoConverter mappingMongoConverter(ObjectProvider<MongoDatabaseFactory> factory,
+			MongoMappingContext context, MongoCustomConversions conversions) {
+		MongoDatabaseFactory mongoDatabaseFactory = factory.getIfAvailable();
+		DbRefResolver dbRefResolver = (mongoDatabaseFactory != null) ? new DefaultDbRefResolver(mongoDatabaseFactory)
+				: NoOpDbRefResolver.INSTANCE;
+		MappingMongoConverter mappingConverter = new MappingMongoConverter(dbRefResolver, context);
+		mappingConverter.setCustomConversions(conversions);
+		return mappingConverter;
+	}
+
 }

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/data/mongo/MongoDatabaseFactoryDependentConfiguration.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2024 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.
@@ -33,12 +33,7 @@
 import org.springframework.data.mongodb.MongoDatabaseFactory;
 import org.springframework.data.mongodb.core.MongoOperations;
 import org.springframework.data.mongodb.core.MongoTemplate;
-import org.springframework.data.mongodb.core.convert.DbRefResolver;
-import org.springframework.data.mongodb.core.convert.DefaultDbRefResolver;
-import org.springframework.data.mongodb.core.convert.MappingMongoConverter;
 import org.springframework.data.mongodb.core.convert.MongoConverter;
-import org.springframework.data.mongodb.core.convert.MongoCustomConversions;
-import org.springframework.data.mongodb.core.mapping.MongoMappingContext;
 import org.springframework.data.mongodb.gridfs.GridFsOperations;
 import org.springframework.data.mongodb.gridfs.GridFsTemplate;
 import org.springframework.util.Assert;
@@ -61,16 +56,6 @@ MongoTemplate mongoTemplate(MongoDatabaseFactory factory, MongoConverter convert
 		return new MongoTemplate(factory, converter);
 	}
 
-	@Bean
-	@ConditionalOnMissingBean(MongoConverter.class)
-	MappingMongoConverter mappingMongoConverter(MongoDatabaseFactory factory, MongoMappingContext context,
-			MongoCustomConversions conversions) {
-		DbRefResolver dbRefResolver = new DefaultDbRefResolver(factory);
-		MappingMongoConverter mappingConverter = new MappingMongoConverter(dbRefResolver, context);
-		mappingConverter.setCustomConversions(conversions);
-		return mappingConverter;
-	}
-
 	@Bean
 	@ConditionalOnMissingBean(GridFsOperations.class)
 	GridFsTemplate gridFsTemplate(MongoProperties properties, MongoDatabaseFactory factory, MongoTemplate mongoTemplate,

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/data/mongo/MongoReactiveDataAutoConfiguration.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2024 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.
@@ -48,9 +48,6 @@
 import org.springframework.data.mongodb.core.SimpleReactiveMongoDatabaseFactory;
 import org.springframework.data.mongodb.core.convert.MappingMongoConverter;
 import org.springframework.data.mongodb.core.convert.MongoConverter;
-import org.springframework.data.mongodb.core.convert.MongoCustomConversions;
-import org.springframework.data.mongodb.core.convert.NoOpDbRefResolver;
-import org.springframework.data.mongodb.core.mapping.MongoMappingContext;
 import org.springframework.data.mongodb.gridfs.ReactiveGridFsOperations;
 import org.springframework.data.mongodb.gridfs.ReactiveGridFsTemplate;
 import org.springframework.util.StringUtils;
@@ -101,15 +98,6 @@ public ReactiveMongoTemplate reactiveMongoTemplate(ReactiveMongoDatabaseFactory
 		return new ReactiveMongoTemplate(reactiveMongoDatabaseFactory, converter);
 	}
 
-	@Bean
-	@ConditionalOnMissingBean(MongoConverter.class)
-	public MappingMongoConverter mappingMongoConverter(MongoMappingContext context,
-			MongoCustomConversions conversions) {
-		MappingMongoConverter mappingConverter = new MappingMongoConverter(NoOpDbRefResolver.INSTANCE, context);
-		mappingConverter.setCustomConversions(conversions);
-		return mappingConverter;
-	}
-
 	@Bean
 	@ConditionalOnMissingBean(DataBufferFactory.class)
 	public DefaultDataBufferFactory dataBufferFactory() {

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/data/mongo/MongoDataAutoConfigurationTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2024 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.
@@ -50,6 +50,8 @@
 import org.springframework.data.mongodb.MongoDatabaseFactory;
 import org.springframework.data.mongodb.core.MongoTemplate;
 import org.springframework.data.mongodb.core.SimpleMongoClientDatabaseFactory;
+import org.springframework.data.mongodb.core.convert.DefaultDbRefResolver;
+import org.springframework.data.mongodb.core.convert.MappingMongoConverter;
 import org.springframework.data.mongodb.core.convert.MongoCustomConversions;
 import org.springframework.data.mongodb.core.mapping.MongoMappingContext;
 import org.springframework.data.mongodb.core.mapping.MongoPersistentEntity;
@@ -319,6 +321,14 @@ public ConnectionString getConnectionString() {
 				.doesNotHaveBean(PropertiesMongoConnectionDetails.class));
 	}
 
+	@Test
+	void mappingMongoConverterHasADefaultDbRefResolver() {
+		this.contextRunner.run((context) -> {
+			MappingMongoConverter converter = context.getBean(MappingMongoConverter.class);
+			assertThat(converter).extracting("dbRefResolver").isInstanceOf(DefaultDbRefResolver.class);
+		});
+	}
+
 	private static void assertDomainTypesDiscovered(MongoMappingContext mappingContext, Class<?>... types) {
 		ManagedTypes managedTypes = (ManagedTypes) ReflectionTestUtils.getField(mappingContext, "managedTypes");
 		assertThat(managedTypes.toList()).containsOnly(types);

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/data/mongo/MongoReactiveDataAutoConfigurationTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2024 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.
@@ -35,6 +35,8 @@
 import org.springframework.data.mongodb.ReactiveMongoDatabaseFactory;
 import org.springframework.data.mongodb.core.ReactiveMongoTemplate;
 import org.springframework.data.mongodb.core.SimpleReactiveMongoDatabaseFactory;
+import org.springframework.data.mongodb.core.convert.MappingMongoConverter;
+import org.springframework.data.mongodb.core.convert.NoOpDbRefResolver;
 import org.springframework.data.mongodb.gridfs.ReactiveGridFsTemplate;
 import org.springframework.test.util.ReflectionTestUtils;
 
@@ -161,6 +163,14 @@ void contextFailsWhenDatabaseNotSet() {
 			.run((context) -> assertThat(context).getFailure().hasMessageContaining("Database name must not be empty"));
 	}
 
+	@Test
+	void mappingMongoConverterHasANoOpDbRefResolver() {
+		this.contextRunner.run((context) -> {
+			MappingMongoConverter converter = context.getBean(MappingMongoConverter.class);
+			assertThat(converter).extracting("dbRefResolver").isInstanceOf(NoOpDbRefResolver.class);
+		});
+	}
+
 	@SuppressWarnings("unchecked")
 	private String grisFsTemplateDatabaseName(AssertableApplicationContext context) {
 		assertThat(context).hasSingleBean(ReactiveGridFsTemplate.class);