DATAMONGO-2004 - Support lazy DBRef resolution through constructor creation of the enclosing entity.

pom.xml

@@ -5,7 +5,7 @@
 
 	<groupId>org.springframework.data</groupId>
 	<artifactId>spring-data-mongodb-parent</artifactId>
-	<version>2.1.0.BUILD-SNAPSHOT</version>
+	<version>2.1.0.DATAMONGO-2004-SNAPSHOT</version>
 	<packaging>pom</packaging>
 
 	<name>Spring Data MongoDB</name>

spring-data-mongodb-benchmarks/pom.xml

@@ -7,7 +7,7 @@
 	<parent>
 		<groupId>org.springframework.data</groupId>
 		<artifactId>spring-data-mongodb-parent</artifactId>
-		<version>2.1.0.BUILD-SNAPSHOT</version>
+		<version>2.1.0.DATAMONGO-2004-SNAPSHOT</version>
 		<relativePath>../pom.xml</relativePath>
 	</parent>
 

spring-data-mongodb-cross-store/pom.xml

@@ -6,7 +6,7 @@
 	<parent>
 		<groupId>org.springframework.data</groupId>
 		<artifactId>spring-data-mongodb-parent</artifactId>
-		<version>2.1.0.BUILD-SNAPSHOT</version>
+		<version>2.1.0.DATAMONGO-2004-SNAPSHOT</version>
 		<relativePath>../pom.xml</relativePath>
 	</parent>
 
@@ -50,7 +50,7 @@
 		<dependency>
 			<groupId>org.springframework.data</groupId>
 			<artifactId>spring-data-mongodb</artifactId>
-			<version>2.1.0.BUILD-SNAPSHOT</version>
+			<version>2.1.0.DATAMONGO-2004-SNAPSHOT</version>
 		</dependency>
 
 		<!-- reactive -->

spring-data-mongodb-distribution/pom.xml

@@ -13,7 +13,7 @@
 	<parent>
 		<groupId>org.springframework.data</groupId>
 		<artifactId>spring-data-mongodb-parent</artifactId>
-		<version>2.1.0.BUILD-SNAPSHOT</version>
+		<version>2.1.0.DATAMONGO-2004-SNAPSHOT</version>
 		<relativePath>../pom.xml</relativePath>
 	</parent>
 

spring-data-mongodb/pom.xml

@@ -11,7 +11,7 @@
 	<parent>
 		<groupId>org.springframework.data</groupId>
 		<artifactId>spring-data-mongodb-parent</artifactId>
-		<version>2.1.0.BUILD-SNAPSHOT</version>
+		<version>2.1.0.DATAMONGO-2004-SNAPSHOT</version>
 		<relativePath>../pom.xml</relativePath>
 	</parent>
 

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/DocumentAccessor.java

@@ -58,6 +58,14 @@ public DocumentAccessor(Bson document) {
 		this.document = document;
 	}
 
+	/**
+	 * @return the underlying {@link Bson document}.
+	 * @since 2.1
+	 */
+	public Bson getDocument() {
+		return this.document;
+	}
+
 	/**
 	 * Puts the given value into the backing {@link Document} based on the coordinates defined through the given
 	 * {@link MongoPersistentProperty}. By default this will be the plain field name. But field names might also consist

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/MappingMongoConverter.java

@@ -255,7 +255,8 @@ private <S extends Object> S read(TypeInformation<S> type, @Nullable Bson bson,
 	private ParameterValueProvider<MongoPersistentProperty> getParameterProvider(MongoPersistentEntity<?> entity,
 			Bson source, DefaultSpELExpressionEvaluator evaluator, ObjectPath path) {
 
-		MongoDbPropertyValueProvider provider = new MongoDbPropertyValueProvider(source, evaluator, path);
+		AssociationAwareMongoDbPropertyValueProvider provider = new AssociationAwareMongoDbPropertyValueProvider(source,
+				evaluator, path);
 		PersistentEntityParameterValueProvider<MongoPersistentProperty> parameterProvider = new PersistentEntityParameterValueProvider<>(
 				entity, provider, path.getCurrentObject());
 
@@ -659,7 +660,8 @@ protected Bson createMap(Map<Object, Object> map, MongoPersistentProperty proper
 	 * @param sink the {@link Collection} to write to.
 	 * @return
 	 */
-	private List<Object> writeCollectionInternal(Collection<?> source, @Nullable TypeInformation<?> type, Collection<?> sink) {
+	private List<Object> writeCollectionInternal(Collection<?> source, @Nullable TypeInformation<?> type,
+			Collection<?> sink) {
 
 		TypeInformation<?> componentType = null;
 
@@ -867,7 +869,7 @@ private Object getPotentiallyConvertedSimpleWrite(@Nullable Object value) {
 	 */
 	@Nullable
 	@SuppressWarnings({ "rawtypes", "unchecked" })
-	private Object getPotentiallyConvertedSimpleRead(@Nullable Object value, @Nullable  Class<?> target) {
+	private Object getPotentiallyConvertedSimpleRead(@Nullable Object value, @Nullable Class<?> target) {
 
 		if (value == null || target == null || ClassUtils.isAssignableValue(target, value)) {
 			return value;
@@ -1270,12 +1272,14 @@ private Object removeTypeInfo(Object object, boolean recursively) {
 	 * of the configured source {@link Document}.
 	 *
 	 * @author Oliver Gierke
+	 * @author Mark Paluch
+	 * @author Christoph Strobl
 	 */
 	class MongoDbPropertyValueProvider implements PropertyValueProvider<MongoPersistentProperty> {
 
-		private final DocumentAccessor source;
-		private final SpELExpressionEvaluator evaluator;
-		private final ObjectPath path;
+		final DocumentAccessor source;
+		final SpELExpressionEvaluator evaluator;
+		final ObjectPath path;
 
 		/**
 		 * Creates a new {@link MongoDbPropertyValueProvider} for the given source, {@link SpELExpressionEvaluator} and
@@ -1285,15 +1289,8 @@ class MongoDbPropertyValueProvider implements PropertyValueProvider<MongoPersist
 		 * @param evaluator must not be {@literal null}.
 		 * @param path must not be {@literal null}.
 		 */
-		public MongoDbPropertyValueProvider(Bson source, SpELExpressionEvaluator evaluator, ObjectPath path) {
-
-			Assert.notNull(source, "Source document must no be null!");
-			Assert.notNull(evaluator, "SpELExpressionEvaluator must not be null!");
-			Assert.notNull(path, "ObjectPath must not be null!");
-
-			this.source = new DocumentAccessor(source);
-			this.evaluator = evaluator;
-			this.path = path;
+		MongoDbPropertyValueProvider(Bson source, SpELExpressionEvaluator evaluator, ObjectPath path) {
+			this(new DocumentAccessor(source), evaluator, path);
 		}
 
 		/**
@@ -1304,7 +1301,7 @@ public MongoDbPropertyValueProvider(Bson source, SpELExpressionEvaluator evaluat
 		 * @param evaluator must not be {@literal null}.
 		 * @param path must not be {@literal null}.
 		 */
-		public MongoDbPropertyValueProvider(DocumentAccessor accessor, SpELExpressionEvaluator evaluator, ObjectPath path) {
+		MongoDbPropertyValueProvider(DocumentAccessor accessor, SpELExpressionEvaluator evaluator, ObjectPath path) {
 
 			Assert.notNull(accessor, "DocumentAccessor must no be null!");
 			Assert.notNull(evaluator, "SpELExpressionEvaluator must not be null!");
@@ -1320,6 +1317,7 @@ public MongoDbPropertyValueProvider(DocumentAccessor accessor, SpELExpressionEva
 		 * @see org.springframework.data.convert.PropertyValueProvider#getPropertyValue(org.springframework.data.mapping.PersistentProperty)
 		 */
 		@Nullable
+		@SuppressWarnings("unchecked")
 		public <T> T getPropertyValue(MongoPersistentProperty property) {
 
 			String expression = property.getSpelExpression();
@@ -1333,6 +1331,54 @@ public <T> T getPropertyValue(MongoPersistentProperty property) {
 		}
 	}
 
+	/**
+	 * {@link PropertyValueProvider} that is aware of {@link MongoPersistentProperty#isAssociation()} and that delegates
+	 * resolution to {@link DbRefResolver}.
+	 *
+	 * @author Mark Paluch
+	 * @author Christoph Strobl
+	 * @since 2.1
+	 */
+	class AssociationAwareMongoDbPropertyValueProvider extends MongoDbPropertyValueProvider {
+
+		/**
+		 * Creates a new {@link AssociationAwareMongoDbPropertyValueProvider} for the given source,
+		 * {@link SpELExpressionEvaluator} and {@link ObjectPath}.
+		 *
+		 * @param source must not be {@literal null}.
+		 * @param evaluator must not be {@literal null}.
+		 * @param path must not be {@literal null}.
+		 */
+		AssociationAwareMongoDbPropertyValueProvider(Bson source, SpELExpressionEvaluator evaluator, ObjectPath path) {
+			super(source, evaluator, path);
+		}
+
+		/*
+		 * (non-Javadoc)
+		 * @see org.springframework.data.convert.PropertyValueProvider#getPropertyValue(org.springframework.data.mapping.PersistentProperty)
+		 */
+		@Nullable
+		@SuppressWarnings("unchecked")
+		public <T> T getPropertyValue(MongoPersistentProperty property) {
+
+			if (property.isDbReference() && property.getDBRef().lazy()) {
+
+				Object rawRefValue = source.get(property);
+				if (rawRefValue == null) {
+					return null;
+				}
+
+				DbRefResolverCallback callback = new DefaultDbRefResolverCallback(source.getDocument(), path, evaluator,
+						MappingMongoConverter.this);
+
+				DBRef dbref = rawRefValue instanceof DBRef ? (DBRef) rawRefValue : null;
+				return (T) dbRefResolver.resolveDbRef(property, dbref, callback, dbRefProxyHandler);
+			}
+
+			return super.getPropertyValue(property);
+		}
+	}
+
 	/**
 	 * Extension of {@link SpELExpressionParameterValueProvider} to recursively trigger value conversion on the raw
 	 * resolved SpEL value.

spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/MongoTemplateTests.java

@@ -3069,8 +3069,8 @@ public void resolvesCyclicDBRefCorrectly() {
 		assertThat(contentLoaded.dbrefMessage.id, is(messageLoaded.id));
 	}
 
-	@Test // DATAMONGO-1287
-	public void shouldReuseAlreadyResolvedLazyLoadedDBRefWhenUsedAsPersistenceConstrcutorArgument() {
+	@Test // DATAMONGO-1287, DATAMONGO-2004
+	public void shouldReuseAlreadyResolvedLazyLoadedDBRefWhenUsedAsPersistenceConstructorArgument() {
 
 		Document docInCtor = new Document();
 		docInCtor.id = "doc-in-ctor";
@@ -3083,7 +3083,7 @@ public void shouldReuseAlreadyResolvedLazyLoadedDBRefWhenUsedAsPersistenceConstr
 
 		DocumentWithLazyDBrefUsedInPresistenceConstructor loaded = template.findOne(query(where("id").is(source.id)),
 				DocumentWithLazyDBrefUsedInPresistenceConstructor.class);
-		assertThat(loaded.refToDocUsedInCtor, not(instanceOf(LazyLoadingProxy.class)));
+		assertThat(loaded.refToDocUsedInCtor, instanceOf(LazyLoadingProxy.class));
 		assertThat(loaded.refToDocNotUsedInCtor, nullValue());
 	}
 
@@ -3106,8 +3106,8 @@ public void shouldNotReuseLazyLoadedDBRefWhenTypeUsedInPersistenceConstrcutorBut
 		assertThat(loaded.refToDocUsedInCtor, nullValue());
 	}
 
-	@Test // DATAMONGO-1287
-	public void shouldRespectParamterValueWhenAttemptingToReuseLazyLoadedDBRefUsedInPersistenceConstrcutor() {
+	@Test // DATAMONGO-1287, DATAMONGO-2004
+	public void shouldRespectParameterValueWhenAttemptingToReuseLazyLoadedDBRefUsedInPersistenceConstructor() {
 
 		Document docInCtor = new Document();
 		docInCtor.id = "doc-in-ctor";
@@ -3125,7 +3125,7 @@ public void shouldRespectParamterValueWhenAttemptingToReuseLazyLoadedDBRefUsedIn
 
 		DocumentWithLazyDBrefUsedInPresistenceConstructor loaded = template.findOne(query(where("id").is(source.id)),
 				DocumentWithLazyDBrefUsedInPresistenceConstructor.class);
-		assertThat(loaded.refToDocUsedInCtor, not(instanceOf(LazyLoadingProxy.class)));
+		assertThat(loaded.refToDocUsedInCtor, instanceOf(LazyLoadingProxy.class));
 		assertThat(loaded.refToDocNotUsedInCtor, instanceOf(LazyLoadingProxy.class));
 	}
 
@@ -3384,6 +3384,73 @@ public void shouldFetchMapOfLazyReferencesCorrectly() {
 		assertThat(target.lazyDbRefAnnotatedMap.values(), contains(two, one));
 	}
 
+	@Test // DATAMONGO-2004
+	public void shouldFetchLazyReferenceWithConstructorCreationCorrectly() {
+
+		Sample one = new Sample("1", "jon snow");
+
+		template.save(one);
+
+		DocumentWithLazyDBRefsAndConstructorCreation source = new DocumentWithLazyDBRefsAndConstructorCreation(null, one,
+				null, null);
+
+		template.save(source);
+
+		DocumentWithLazyDBRefsAndConstructorCreation target = template.findOne(query(where("id").is(source.id)),
+				DocumentWithLazyDBRefsAndConstructorCreation.class);
+
+		assertThat(target.lazyDbRefProperty, instanceOf(LazyLoadingProxy.class));
+		assertThat(target.lazyDbRefProperty, is(one));
+	}
+
+	@Test // DATAMONGO-2004
+	public void shouldFetchMapOfLazyReferencesWithConstructorCreationCorrectly() {
+
+		Sample one = new Sample("1", "jon snow");
+		Sample two = new Sample("2", "tyrion lannister");
+
+		template.save(one);
+		template.save(two);
+
+		Map<String, Sample> map = new LinkedHashMap<>();
+		map.put("tyrion", two);
+		map.put("jon", one);
+
+		DocumentWithLazyDBRefsAndConstructorCreation source = new DocumentWithLazyDBRefsAndConstructorCreation(null, null,
+				null, map);
+
+		template.save(source);
+
+		DocumentWithLazyDBRefsAndConstructorCreation target = template.findOne(query(where("id").is(source.id)),
+				DocumentWithLazyDBRefsAndConstructorCreation.class);
+
+		assertThat(target.lazyDbRefAnnotatedMap, instanceOf(LazyLoadingProxy.class));
+		assertThat(target.lazyDbRefAnnotatedMap.values(), contains(two, one));
+	}
+
+	@Test // DATAMONGO-2004
+	public void shouldFetchListOfLazyReferencesWithConstructorCreationCorrectly() {
+
+		Sample one = new Sample("1", "jon snow");
+		Sample two = new Sample("2", "tyrion lannister");
+
+		template.save(one);
+		template.save(two);
+
+		List<Sample> list = Arrays.asList(two, one);
+
+		DocumentWithLazyDBRefsAndConstructorCreation source = new DocumentWithLazyDBRefsAndConstructorCreation(null, null,
+				list, null);
+
+		template.save(source);
+
+		DocumentWithLazyDBRefsAndConstructorCreation target = template.findOne(query(where("id").is(source.id)),
+				DocumentWithLazyDBRefsAndConstructorCreation.class);
+
+		assertThat(target.lazyDbRefAnnotatedList, instanceOf(LazyLoadingProxy.class));
+		assertThat(target.getLazyDbRefAnnotatedList(), contains(two, one));
+	}
+
 	@Test // DATAMONGO-1513
 	@DirtiesContext
 	public void populatesIdsAddedByEventListener() {
@@ -3590,6 +3657,29 @@ static class DocumentWithDBRefCollection {
 		@org.springframework.data.mongodb.core.mapping.DBRef(lazy = true) public Map<String, Sample> lazyDbRefAnnotatedMap;
 	}
 
+	@Data
+	static class DocumentWithLazyDBRefsAndConstructorCreation {
+
+		@Id public final String id;
+
+		public DocumentWithLazyDBRefsAndConstructorCreation(String id, Sample lazyDbRefProperty,
+				List<Sample> lazyDbRefAnnotatedList, Map<String, Sample> lazyDbRefAnnotatedMap) {
+			this.id = id;
+			this.lazyDbRefProperty = lazyDbRefProperty;
+			this.lazyDbRefAnnotatedList = lazyDbRefAnnotatedList;
+			this.lazyDbRefAnnotatedMap = lazyDbRefAnnotatedMap;
+		}
+
+		@org.springframework.data.mongodb.core.mapping.DBRef(lazy = true) //
+		public final Sample lazyDbRefProperty;
+
+		@Field("lazy_db_ref_list") @org.springframework.data.mongodb.core.mapping.DBRef(lazy = true) //
+		public final List<Sample> lazyDbRefAnnotatedList;
+
+		@Field("lazy_db_ref_map") @org.springframework.data.mongodb.core.mapping.DBRef(
+				lazy = true) public final Map<String, Sample> lazyDbRefAnnotatedMap;
+	}
+
 	@EqualsAndHashCode
 	static class DocumentWithCollection {