Simplify usage of user provided aggregation operations.

pom.xml

@@ -5,7 +5,7 @@
 
 	<groupId>org.springframework.data</groupId>
 	<artifactId>spring-data-mongodb-parent</artifactId>
-	<version>4.0.0-SNAPSHOT</version>
+	<version>4.0.0-GH-4038-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>4.0.0-SNAPSHOT</version>
+		<version>4.0.0-GH-4038-SNAPSHOT</version>
 		<relativePath>../pom.xml</relativePath>
 	</parent>
 

spring-data-mongodb-distribution/pom.xml

@@ -15,7 +15,7 @@
 	<parent>
 		<groupId>org.springframework.data</groupId>
 		<artifactId>spring-data-mongodb-parent</artifactId>
-		<version>4.0.0-SNAPSHOT</version>
+		<version>4.0.0-GH-4038-SNAPSHOT</version>
 		<relativePath>../pom.xml</relativePath>
 	</parent>
 

spring-data-mongodb/pom.xml

@@ -12,7 +12,7 @@
   <parent>
     <groupId>org.springframework.data</groupId>
     <artifactId>spring-data-mongodb-parent</artifactId>
-    <version>4.0.0-SNAPSHOT</version>
+    <version>4.0.0-GH-4038-SNAPSHOT</version>
     <relativePath>../pom.xml</relativePath>
   </parent>
 

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

@@ -21,6 +21,7 @@
 import java.util.List;
 
 import org.bson.Document;
+import org.bson.conversions.Bson;
 import org.springframework.data.domain.Sort;
 import org.springframework.data.domain.Sort.Direction;
 import org.springframework.data.mongodb.core.aggregation.AddFieldsOperation.AddFieldsOperationBuilder;
@@ -238,6 +239,40 @@ public static AddFieldsOperationBuilder addFields() {
 		return AddFieldsOperation.builder();
 	}
 
+	/**
+	 * Creates a new {@link AggregationOperation} taking the given {@link Bson bson value} as is. <br />
+	 *
+	 * <pre class="code">
+	 * Aggregation.stage(Aggregates.search(exists(fieldPath("..."))));
+	 * </pre>
+	 *
+	 * Field mapping against a potential domain type or previous aggregation stages will not happen.
+	 *
+	 * @param aggregationOperation the must not be {@literal null}.
+	 * @return new instance of {@link AggregationOperation}.
+	 * @since 4.0
+	 */
+	public static AggregationOperation stage(Bson aggregationOperation) {
+		return new BasicAggregationOperation(aggregationOperation);
+	}
+
+	/**
+	 * Creates a new {@link AggregationOperation} taking the given {@link String json value} as is. <br />
+	 *
+	 * <pre class="code">
+	 * Aggregation.stage("{ $search : { near : { path : 'released' , origin : ... } } }");
+	 * </pre>
+	 *
+	 * Field mapping against a potential domain type or previous aggregation stages will not happen.
+	 *
+	 * @param json the JSON representation of the pipeline stage. Must not be {@literal null}.
+	 * @return new instance of {@link AggregationOperation}.
+	 * @since 4.0
+	 */
+	public static AggregationOperation stage(String json) {
+		return new BasicAggregationOperation(json);
+	}
+
 	/**
 	 * Creates a new {@link ProjectionOperation} including the given fields.
 	 *

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

@@ -20,20 +20,24 @@
 import java.util.Arrays;
 
 import org.bson.Document;
+import org.bson.codecs.configuration.CodecRegistry;
 import org.springframework.beans.BeanUtils;
+import org.springframework.data.mongodb.CodecRegistryProvider;
 import org.springframework.data.mongodb.core.aggregation.ExposedFields.FieldReference;
 import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.ReflectionUtils;
 
+import com.mongodb.MongoClientSettings;
+
 /**
  * The context for an {@link AggregationOperation}.
  *
  * @author Oliver Gierke
  * @author Christoph Strobl
  * @since 1.3
  */
-public interface AggregationOperationContext {
+public interface AggregationOperationContext extends CodecRegistryProvider {
 
 	/**
 	 * Returns the mapped {@link Document}, potentially converting the source considering mapping metadata etc.
@@ -114,4 +118,9 @@ default Fields getFields(Class<?> type) {
 	default AggregationOperationContext continueOnMissingFieldReference() {
 		return this;
 	}
+
+	@Override
+	default CodecRegistry getCodecRegistry() {
+		return MongoClientSettings.getDefaultCodecRegistry();
+	}
 }

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

@@ -0,0 +1,61 @@
+/*
+ * Copyright 2022 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.core.aggregation;
+
+import java.util.Map;
+
+import org.bson.Document;
+import org.bson.conversions.Bson;
+import org.springframework.data.mongodb.util.BsonUtils;
+import org.springframework.util.ObjectUtils;
+
+/**
+ * {@link AggregationOperation} implementation that c
+ * 
+ * @author Christoph Strobl
+ * @since 4.0
+ */
+class BasicAggregationOperation implements AggregationOperation {
+
+	private final Object value;
+
+	BasicAggregationOperation(Object value) {
+		this.value = value;
+	}
+
+	@Override
+	public Document toDocument(AggregationOperationContext context) {
+
+		if (value instanceof Document document) {
+			return document;
+		}
+
+		if (value instanceof Bson bson) {
+			return BsonUtils.asDocument(bson, context.getCodecRegistry());
+		}
+
+		if (value instanceof Map map) {
+			return new Document(map);
+		}
+
+		if (value instanceof String json && BsonUtils.isJsonDocument(json)) {
+			return BsonUtils.parse(json, context);
+		}
+
+		throw new IllegalStateException(
+				String.format("%s cannot be converted to org.bson.Document.", ObjectUtils.nullSafeClassName(value)));
+	}
+}

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

@@ -16,6 +16,7 @@
 package org.springframework.data.mongodb.core.aggregation;
 
 import org.bson.Document;
+import org.bson.codecs.configuration.CodecRegistry;
 import org.springframework.data.mongodb.core.aggregation.ExposedFields.DirectFieldReference;
 import org.springframework.data.mongodb.core.aggregation.ExposedFields.ExposedField;
 import org.springframework.data.mongodb.core.aggregation.ExposedFields.FieldReference;
@@ -141,4 +142,9 @@ protected FieldReference resolveExposedField(@Nullable Field field, String name)
 	AggregationOperationContext getRootContext() {
 		return rootContext;
 	}
+
+	@Override
+	public CodecRegistry getCodecRegistry() {
+		return getRootContext().getCodecRegistry();
+	}
 }

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

@@ -19,6 +19,7 @@
 
 import org.bson.Document;
 
+import org.bson.codecs.configuration.CodecRegistry;
 import org.springframework.data.mongodb.core.aggregation.ExposedFields.ExpressionFieldReference;
 import org.springframework.data.mongodb.core.aggregation.ExposedFields.FieldReference;
 import org.springframework.util.Assert;
@@ -92,4 +93,9 @@ public FieldReference getReference(String name) {
 	public Fields getFields(Class<?> type) {
 		return delegate.getFields(type);
 	}
+
+	@Override
+	public CodecRegistry getCodecRegistry() {
+		return delegate.getCodecRegistry();
+	}
 }

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

@@ -24,6 +24,7 @@
 import java.util.Set;
 
 import org.bson.Document;
+import org.bson.codecs.configuration.CodecRegistry;
 import org.springframework.data.mongodb.core.aggregation.ExposedFields.FieldReference;
 import org.springframework.lang.Nullable;
 
@@ -80,6 +81,11 @@ public Fields getFields(Class<?> type) {
 		return delegate.getFields(type);
 	}
 
+	@Override
+	public CodecRegistry getCodecRegistry() {
+		return delegate.getCodecRegistry();
+	}
+
 	@SuppressWarnings("unchecked")
 	private Document doPrefix(Document source) {
 

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

@@ -22,6 +22,7 @@
 
 import org.bson.Document;
 
+import org.bson.codecs.configuration.CodecRegistry;
 import org.springframework.data.mapping.PersistentPropertyPath;
 import org.springframework.data.mapping.context.MappingContext;
 import org.springframework.data.mongodb.core.aggregation.ExposedFields.DirectFieldReference;
@@ -147,4 +148,9 @@ protected FieldReference getReferenceFor(Field field) {
 	public Class<?> getType() {
 		return type;
 	}
+
+	@Override
+	public CodecRegistry getCodecRegistry() {
+		return this.mapper.getConverter().getCodecRegistry();
+	}
 }

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

@@ -26,6 +26,7 @@
 import org.bson.Document;
 import org.bson.codecs.Codec;
 import org.bson.codecs.DecoderContext;
+import org.bson.codecs.configuration.CodecRegistry;
 import org.bson.conversions.Bson;
 import org.bson.json.JsonReader;
 import org.bson.types.ObjectId;
@@ -1793,6 +1794,11 @@ public Class<?> getWriteTarget(Class<?> source) {
 		return conversions.getCustomWriteTarget(source).orElse(source);
 	}
 
+	@Override
+	public CodecRegistry getCodecRegistry() {
+		return codecRegistryProvider != null ? codecRegistryProvider.getCodecRegistry() : super.getCodecRegistry();
+	}
+
 	/**
 	 * Create a new {@link MappingMongoConverter} using the given {@link MongoDatabaseFactory} when loading {@link DBRef}.
 	 *

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

@@ -15,16 +15,18 @@
  */
 package org.springframework.data.mongodb.core.convert;
 
+import com.mongodb.MongoClientSettings;
 import org.bson.BsonValue;
 import org.bson.Document;
+import org.bson.codecs.configuration.CodecRegistry;
 import org.bson.conversions.Bson;
 import org.bson.types.ObjectId;
-
 import org.springframework.core.convert.ConversionException;
 import org.springframework.data.convert.CustomConversions;
 import org.springframework.data.convert.EntityConverter;
 import org.springframework.data.convert.EntityReader;
 import org.springframework.data.convert.TypeMapper;
+import org.springframework.data.mongodb.CodecRegistryProvider;
 import org.springframework.data.mongodb.core.mapping.MongoPersistentEntity;
 import org.springframework.data.mongodb.core.mapping.MongoPersistentProperty;
 import org.springframework.data.mongodb.util.BsonUtils;
@@ -48,7 +50,7 @@
  */
 public interface MongoConverter
 		extends EntityConverter<MongoPersistentEntity<?>, MongoPersistentProperty, Object, Bson>, MongoWriter<Object>,
-		EntityReader<Object, Bson> {
+		EntityReader<Object, Bson>, CodecRegistryProvider {
 
 	/**
 	 * Returns the {@link TypeMapper} being used to write type information into {@link Document}s created with that
@@ -188,4 +190,9 @@ default Object convertId(@Nullable Object id, Class<?> targetType) {
 		}
 	}
 
+	@Override
+	default CodecRegistry getCodecRegistry() {
+		return MongoClientSettings.getDefaultCodecRegistry();
+	}
+
 }

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

@@ -1486,4 +1486,8 @@ public String convert(MongoPersistentProperty source) {
 	public MappingContext<? extends MongoPersistentEntity<?>, MongoPersistentProperty> getMappingContext() {
 		return mappingContext;
 	}
+
+	public MongoConverter getConverter() {
+		return converter;
+	}
 }