DATAMONGO-2153 - Aggregation support for repositories.

pom.xml

@@ -5,7 +5,7 @@
 
 	<groupId>org.springframework.data</groupId>
 	<artifactId>spring-data-mongodb-parent</artifactId>
-	<version>2.2.0.BUILD-SNAPSHOT</version>
+	<version>2.2.0.DATAMONGO-2153-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>2.2.0.BUILD-SNAPSHOT</version>
+		<version>2.2.0.DATAMONGO-2153-SNAPSHOT</version>
 		<relativePath>../pom.xml</relativePath>
 	</parent>
 

spring-data-mongodb-distribution/pom.xml

@@ -14,7 +14,7 @@
 	<parent>
 		<groupId>org.springframework.data</groupId>
 		<artifactId>spring-data-mongodb-parent</artifactId>
-		<version>2.2.0.BUILD-SNAPSHOT</version>
+		<version>2.2.0.DATAMONGO-2153-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>2.2.0.BUILD-SNAPSHOT</version>
+		<version>2.2.0.DATAMONGO-2153-SNAPSHOT</version>
 		<relativePath>../pom.xml</relativePath>
 	</parent>
 

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/aggregation/AggregationOperationContext.java

@@ -17,6 +17,7 @@
 
 import org.bson.Document;
 import org.springframework.data.mongodb.core.aggregation.ExposedFields.FieldReference;
+import org.springframework.lang.Nullable;
 
 /**
  * The context for an {@link AggregationOperation}.
@@ -33,7 +34,20 @@ public interface AggregationOperationContext {
 	 * @param document will never be {@literal null}.
 	 * @return must not be {@literal null}.
 	 */
-	Document getMappedObject(Document document);
+	default Document getMappedObject(Document document) {
+		return getMappedObject(document, null);
+	}
+
+	/**
+	 * Returns the mapped {@link Document}, potentially converting the source considering mapping metadata for the given
+	 * type.
+	 *
+	 * @param document will never be {@literal null}.
+	 * @param type can be {@literal null}.
+	 * @return must not be {@literal null}.
+	 * @since 2.2
+	 */
+	Document getMappedObject(Document document, @Nullable Class<?> type);
 
 	/**
 	 * Returns a {@link FieldReference} for the given field or {@literal null} if the context does not expose the given

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/aggregation/AggregationOperationRenderer.java

@@ -24,6 +24,7 @@
 import org.springframework.data.mongodb.core.aggregation.ExposedFields.FieldReference;
 import org.springframework.data.mongodb.core.aggregation.Fields.AggregationField;
 import org.springframework.data.mongodb.core.aggregation.FieldsExposingAggregationOperation.InheritsFieldsAggregationOperation;
+import org.springframework.lang.Nullable;
 
 /**
  * Rendering support for {@link AggregationOperation} into a {@link List} of {@link org.bson.Document}.
@@ -75,15 +76,16 @@ static List<Document> toDocument(List<AggregationOperation> operations, Aggregat
 	 * Simple {@link AggregationOperationContext} that just returns {@link FieldReference}s as is.
 	 *
 	 * @author Oliver Gierke
+	 * @author Christoph Strobl
 	 */
 	private static class NoOpAggregationOperationContext implements AggregationOperationContext {
 
 		/*
 		 * (non-Javadoc)
-		 * @see org.springframework.data.mongodb.core.aggregation.AggregationOperationContext#getMappedObject(org.bson.Document)
+		 * @see org.springframework.data.mongodb.core.aggregation.AggregationOperationContext#getMappedObject(org.bson.Document, java.lang.Class)
 		 */
 		@Override
-		public Document getMappedObject(Document document) {
+		public Document getMappedObject(Document document, @Nullable Class<?> type) {
 			return document;
 		}
 

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/aggregation/ExposedFieldsAggregationOperationContext.java

@@ -56,11 +56,11 @@ public ExposedFieldsAggregationOperationContext(ExposedFields exposedFields,
 
 	/*
 	 * (non-Javadoc)
-	 * @see org.springframework.data.mongodb.core.aggregation.AggregationOperationContext#getMappedObject(org.bson.Document)
+	 * @see org.springframework.data.mongodb.core.aggregation.AggregationOperationContext#getMappedObject(org.bson.Document, java.lang.Class)
 	 */
 	@Override
-	public Document getMappedObject(Document document) {
-		return rootContext.getMappedObject(document);
+	public Document getMappedObject(Document document, @Nullable Class<?> type) {
+		return rootContext.getMappedObject(document, type);
 	}
 
 	/*

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/aggregation/NestedDelegatingExpressionAggregationOperationContext.java

@@ -45,11 +45,11 @@ public NestedDelegatingExpressionAggregationOperationContext(AggregationOperatio
 
 	/*
 	 * (non-Javadoc)
-	 * @see org.springframework.data.mongodb.core.aggregation.AggregationOperationContext#getMappedObject(org.bson.Document)
+	 * @see org.springframework.data.mongodb.core.aggregation.AggregationOperationContext#getMappedObject(org.bson.Document, java.lang.Class)
 	 */
 	@Override
-	public Document getMappedObject(Document document) {
-		return delegate.getMappedObject(document);
+	public Document getMappedObject(Document document, Class<?> type) {
+		return delegate.getMappedObject(document, type);
 	}
 
 	/*

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/aggregation/PrefixingDelegatingAggregationOperationContext.java

@@ -25,6 +25,7 @@
 
 import org.bson.Document;
 import org.springframework.data.mongodb.core.aggregation.ExposedFields.FieldReference;
+import org.springframework.lang.Nullable;
 
 /**
  * {@link AggregationOperationContext} implementation prefixing non-command keys on root level with the given prefix.
@@ -56,11 +57,11 @@ public PrefixingDelegatingAggregationOperationContext(AggregationOperationContex
 
 	/*
 	 * (non-Javadoc)
-	 * @see org.springframework.data.mongodb.core.aggregation.AggregationOperationContext#getMappedObject(org.bson.Document)
+	 * @see org.springframework.data.mongodb.core.aggregation.AggregationOperationContext#getMappedObject(org.bson.Document, java.lang.Class)
 	 */
 	@Override
-	public Document getMappedObject(Document document) {
-		return doPrefix(delegate.getMappedObject(document));
+	public Document getMappedObject(Document document, @Nullable Class<?> type) {
+		return doPrefix(delegate.getMappedObject(document, type));
 	}
 
 	/*

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/aggregation/TypeBasedAggregationOperationContext.java

@@ -27,6 +27,7 @@
 import org.springframework.data.mongodb.core.convert.QueryMapper;
 import org.springframework.data.mongodb.core.mapping.MongoPersistentEntity;
 import org.springframework.data.mongodb.core.mapping.MongoPersistentProperty;
+import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**
@@ -70,7 +71,16 @@ public TypeBasedAggregationOperationContext(Class<?> type,
 	 */
 	@Override
 	public Document getMappedObject(Document document) {
-		return mapper.getMappedObject(document, mappingContext.getPersistentEntity(type));
+		return getMappedObject(document, type);
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.mongodb.core.aggregation.AggregationOperationContext#getMappedObject(org.bson.Document, java.lang.Class)
+	 */
+	@Override
+	public Document getMappedObject(Document document, @Nullable Class<?> type) {
+		return mapper.getMappedObject(document, type != null ? mappingContext.getPersistentEntity(type) : null);
 	}
 
 	/*

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/repository/Aggregation.java

@@ -0,0 +1,127 @@
+/*
+ * Copyright 2019 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.repository;
+
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+import org.springframework.core.annotation.AliasFor;
+import org.springframework.data.annotation.QueryAnnotation;
+
+/**
+ * The {@link Aggregation} annotation can be used to annotate a {@link org.springframework.data.repository.Repository}
+ * query method so that it runs the {@link Aggregation#pipeline()} on invocation.
+ * <p />
+ * Pipeline stages are mapped against the {@link org.springframework.data.repository.Repository} domain type to consider
+ * {@link org.springframework.data.mongodb.core.mapping.Field field} mappings and may contain simple placeholders
+ * {@code ?0} as well as {@link org.springframework.expression.spel.standard.SpelExpression SpelExpressions}.
+ * <p />
+ * Query method {@link org.springframework.data.domain.Sort} and {@link org.springframework.data.domain.Pageable}
+ * arguments are applied at the end of the pipeline or can be defined manually as part of it.
+ *
+ * @author Christoph Strobl
+ * @since 2.2
+ */
+@Retention(RetentionPolicy.RUNTIME)
+@Target({ ElementType.METHOD, ElementType.ANNOTATION_TYPE })
+@Documented
+@QueryAnnotation
+public @interface Aggregation {
+
+	/**
+	 * Alias for {@link #pipeline()}. Defines the aggregation pipeline to apply.
+	 *
+	 * @return an empty array by default.
+	 * @see #pipeline()
+	 */
+	@AliasFor("pipeline")
+	String[] value() default {};
+
+	/**
+	 * Defines the aggregation pipeline to apply.
+	 *
+	 * <pre class="code">
+	 *
+	 * // aggregation resulting in collection with single value
+	 * &#64;Aggregation("{ '$project': { '_id' : '$lastname' } }")
+	 * List<String> findAllLastnames();
+	 *
+	 * // aggregation with parameter replacement
+	 * &#64;Aggregation("{ '$group': { '_id' : '$lastname', names : { $addToSet : '$?0' } } }")
+	 * List<PersonAggregate> groupByLastnameAnd(String property);
+	 *
+	 * // aggregation with sort in pipeline
+	 * &#64;Aggregation(pipeline = {"{ '$group': { '_id' : '$lastname', names : { $addToSet : '$?0' } } }", "{ '$sort' : { 'lastname' : -1 } }"})
+	 * List<PersonAggregate> groupByLastnameAnd(String property);
+	 *
+	 * // Sort parameter is used for sorting results
+	 * &#64;Aggregation("{ '$group': { '_id' : '$lastname', names : { $addToSet : '$?0' } } }")
+	 * List<PersonAggregate> groupByLastnameAnd(String property, Sort sort);
+	 *
+	 * // Pageable parameter used for sort, skip and limit
+	 * &#64;Aggregation("{ '$group': { '_id' : '$lastname', names : { $addToSet : '$?0' } } }")
+	 * List<PersonAggregate> groupByLastnameAnd(String property, Pageable page);
+	 *
+	 * // Single value result aggregation.
+	 * &#64;Aggregation("{ '$group' : { '_id' : null, 'total' : { $sum: '$age' } } }")
+	 * Long sumAge();
+	 *
+	 * // Single value wrapped in container object
+	 * &#64;Aggregation("{ '$group' : { '_id' : null, 'total' : { $sum: '$age' } } })
+	 * SumAge sumAgeAndReturnAggregationResultWrapperWithConcreteType();
+	 *
+	 * // Raw aggregation result
+	 * &#64;Aggregation("{ '$group' : { '_id' : null, 'total' : { $sum: '$age' } } })
+	 * AggregationResults&lt;org.bson.Document>&gt; sumAgeAndReturnAggregationResultWrapper();
+	 * </pre>
+	 *
+	 * @return an empty array by default.
+	 */
+	@AliasFor("value")
+	String[] pipeline() default {};
+
+	/**
+	 * Defines the collation to apply when executing the aggregation.
+	 *
+	 * <pre class="code">
+	 * // Fixed value
+	 * &#64;Aggregation(pipeline = "...", collation = "en_US")
+	 * List<Entry> findAllByFixedCollation();
+	 *
+	 * // Fixed value as Document
+	 * &#64;Aggregation(pipeline = "...", collation = "{ 'locale' :  'en_US' }")
+	 * List<Entry> findAllByFixedJsonCollation();
+	 *
+	 * // Dynamic value as String
+	 * &#64;Aggregation(pipeline = "...", collation = "?0")
+	 * List<Entry> findAllByDynamicCollation(String collation);
+	 *
+	 * // Dynamic value as Document
+	 * &#64;Aggregation(pipeline = "...", collation = "{ 'locale' :  ?0 }")
+	 * List<Entry> findAllByDynamicJsonCollation(String collation);
+	 *
+	 * // SpEL expression
+	 * &#64;Aggregation(pipeline = "...", collation = "?#{[0]}")
+	 * List<Entry> findAllByDynamicSpElCollation(String collation);
+	 * </pre>
+	 *
+	 * @return an empty {@link String} by default.
+	 */
+	String collation() default "";
+}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/repository/query/AbstractMongoQuery.java

@@ -16,7 +16,6 @@
 package org.springframework.data.mongodb.repository.query;
 
 import org.bson.Document;
-
 import org.springframework.data.mongodb.core.ExecutableFindOperation.ExecutableFind;
 import org.springframework.data.mongodb.core.ExecutableFindOperation.FindWithQuery;
 import org.springframework.data.mongodb.core.ExecutableFindOperation.TerminatingFind;
@@ -32,6 +31,7 @@
 import org.springframework.data.repository.query.RepositoryQuery;
 import org.springframework.data.repository.query.ResultProcessor;
 import org.springframework.expression.spel.standard.SpelExpressionParser;
+import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**
@@ -94,22 +94,36 @@ public Object execute(Object[] parameters) {
 
 		ConvertingParameterAccessor accessor = new ConvertingParameterAccessor(operations.getConverter(),
 				new MongoParametersParameterAccessor(method, parameters));
+
+		ResultProcessor processor = method.getResultProcessor().withDynamicProjection(accessor);
+		Class<?> typeToRead = processor.getReturnedType().getTypeToRead();
+
+		return processor.processResult(doExecute(method, processor, accessor, typeToRead));
+	}
+
+	/**
+	 * Execute the {@link RepositoryQuery} of the given method with the parameters provided by the
+	 * {@link ConvertingParameterAccessor accessor}
+	 *
+	 * @param method the {@link MongoQueryMethod} invoked. Never {@literal null}.
+	 * @param processor {@link ResultProcessor} for post procession. Never {@literal null}.
+	 * @param accessor for providing invocation arguments. Never {@literal null}.
+	 * @param typeToRead the desired component target type. Can be {@literal null}.
+	 */
+	protected Object doExecute(MongoQueryMethod method, ResultProcessor processor, ConvertingParameterAccessor accessor,
+			@Nullable Class<?> typeToRead) {
+
 		Query query = createQuery(accessor);
 
 		applyQueryMetaAttributesWhenPresent(query);
 		query = applyAnnotatedDefaultSortIfPresent(query);
 		query = applyAnnotatedCollationIfPresent(query, accessor);
 
-		ResultProcessor processor = method.getResultProcessor().withDynamicProjection(accessor);
-		Class<?> typeToRead = processor.getReturnedType().getTypeToRead();
-
 		FindWithQuery<?> find = typeToRead == null //
 				? executableFind //
 				: executableFind.as(typeToRead);
 
-		MongoQueryExecution execution = getExecution(accessor, find);
-
-		return processor.processResult(execution.execute(query));
+		return getExecution(accessor, find).execute(query);
 	}
 
 	private MongoQueryExecution getExecution(ConvertingParameterAccessor accessor, FindWithQuery<?> operation) {