Add DynamoDbIgnoreNulls to support ignoreNulls in nested beans

.changes/next-release/feature-DynamoDBEnhancedClient-865ea0b.json

@@ -0,0 +1,6 @@
+{
+    "category": "DynamoDB Enhanced Client", 
+    "contributor": "", 
+    "type": "feature", 
+    "description": "Added `DynamoDbIgnoreNulls` attribute level annotation that specifies attributes with null values should be ignored. See [#2303](https://github.com/aws/aws-sdk-java-v2/issues/2303)"
+}

services-custom/dynamodb-enhanced/src/main/java/software/amazon/awssdk/enhanced/dynamodb/EnhancedType.java

@@ -574,6 +574,10 @@ public boolean equals(Object o) {
             return false;
         }
 
+        if (documentConfiguration != null ? !documentConfiguration.equals(enhancedType.documentConfiguration) :
+            enhancedType.documentConfiguration != null) {
+            return false;
+        }
         return tableSchema != null ? tableSchema.equals(enhancedType.tableSchema) : enhancedType.tableSchema == null;
     }
 
@@ -583,6 +587,7 @@ public int hashCode() {
         result = 31 * result + rawClass.hashCode();
         result = 31 * result + (rawClassParameters != null ? rawClassParameters.hashCode() : 0);
         result = 31 * result + (tableSchema != null ? tableSchema.hashCode() : 0);
+        result = 31 * result + (documentConfiguration != null ? documentConfiguration.hashCode() : 0);
         return result;
     }
 

services-custom/dynamodb-enhanced/src/main/java/software/amazon/awssdk/enhanced/dynamodb/EnhancedTypeDocumentConfiguration.java

@@ -27,9 +27,11 @@
 public final class EnhancedTypeDocumentConfiguration implements ToCopyableBuilder<EnhancedTypeDocumentConfiguration.Builder,
     EnhancedTypeDocumentConfiguration> {
     private final boolean preserveEmptyObject;
+    private final boolean ignoreNulls;
 
     public EnhancedTypeDocumentConfiguration(Builder builder) {
         this.preserveEmptyObject = builder.preserveEmptyObject != null && builder.preserveEmptyObject;
+        this.ignoreNulls = builder.ignoreNulls != null && builder.ignoreNulls;
     }
 
     /**
@@ -40,6 +42,37 @@ public boolean preserveEmptyObject() {
         return preserveEmptyObject;
     }
 
+    /**
+     * @return whether to ignore attributes with null values in the associated {@link EnhancedType}.
+     */
+    public boolean ignoreNulls() {
+        return ignoreNulls;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (o == null || getClass() != o.getClass()) {
+            return false;
+        }
+
+        EnhancedTypeDocumentConfiguration that = (EnhancedTypeDocumentConfiguration) o;
+
+        if (preserveEmptyObject != that.preserveEmptyObject) {
+            return false;
+        }
+        return ignoreNulls == that.ignoreNulls;
+    }
+
+    @Override
+    public int hashCode() {
+        int result = (preserveEmptyObject ? 1 : 0);
+        result = 31 * result + (ignoreNulls ? 1 : 0);
+        return result;
+    }
+
     @Override
     public Builder toBuilder() {
         return builder().preserveEmptyObject(preserveEmptyObject);
@@ -51,19 +84,29 @@ public static Builder builder() {
 
     public static final class Builder implements CopyableBuilder<Builder, EnhancedTypeDocumentConfiguration> {
         private Boolean preserveEmptyObject;
+        private Boolean ignoreNulls;
 
         private Builder() {
         }
 
         /**
          * Specifies whether to initialize the associated {@link EnhancedType} as empty class when
-         * mapping it to a Java object
+         * mapping it to a Java object. By default, the value is false
          */
         public Builder preserveEmptyObject(Boolean preserveEmptyObject) {
             this.preserveEmptyObject = preserveEmptyObject;
             return this;
         }
 
+        /**
+         * Specifies whether to ignore attributes with null values in the associated {@link EnhancedType}.
+         * By default, the value is false
+         */
+        public Builder ignoreNulls(Boolean ignoreNulls) {
+            this.ignoreNulls = ignoreNulls;
+            return this;
+        }
+
         @Override
         public EnhancedTypeDocumentConfiguration build() {
             return new EnhancedTypeDocumentConfiguration(this);

services-custom/dynamodb-enhanced/src/main/java/software/amazon/awssdk/enhanced/dynamodb/internal/AttributeConfiguration.java

@@ -0,0 +1,66 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License").
+ * You may not use this file except in compliance with the License.
+ * A copy of the License is located at
+ *
+ *  http://aws.amazon.com/apache2.0
+ *
+ * or in the "license" file accompanying this file. This file 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 software.amazon.awssdk.enhanced.dynamodb.internal;
+
+import software.amazon.awssdk.annotations.SdkInternalApi;
+
+/**
+ * Internal configuration for attribute
+ */
+@SdkInternalApi
+public final class AttributeConfiguration {
+    private final boolean preserveEmptyObject;
+    private final boolean ignoreNulls;
+
+    public AttributeConfiguration(Builder builder) {
+        this.preserveEmptyObject = builder.preserveEmptyObject;
+        this.ignoreNulls = builder.ignoreNulls;
+    }
+
+    public boolean preserveEmptyObject() {
+        return preserveEmptyObject;
+    }
+
+    public boolean ignoreNulls() {
+        return ignoreNulls;
+    }
+
+    public static Builder builder() {
+        return new Builder();
+    }
+
+    public static final class Builder {
+        private boolean preserveEmptyObject;
+        private boolean ignoreNulls;
+
+        private Builder() {
+        }
+
+        public Builder preserveEmptyObject(boolean preserveEmptyObject) {
+            this.preserveEmptyObject = preserveEmptyObject;
+            return this;
+        }
+
+        public Builder ignoreNulls(boolean ignoreNulls) {
+            this.ignoreNulls = ignoreNulls;
+            return this;
+        }
+
+        public AttributeConfiguration build() {
+            return new AttributeConfiguration(this);
+        }
+    }
+}

services-custom/dynamodb-enhanced/src/main/java/software/amazon/awssdk/enhanced/dynamodb/internal/converter/attribute/DocumentAttributeConverter.java

@@ -32,6 +32,7 @@ public class DocumentAttributeConverter<T> implements AttributeConverter<T> {
     private final TableSchema<T> tableSchema;
     private final EnhancedType<T> enhancedType;
     private final boolean preserveEmptyObject;
+    private final boolean ignoreNulls;
 
     private DocumentAttributeConverter(TableSchema<T> tableSchema,
                                        EnhancedType<T> enhancedType) {
@@ -40,6 +41,9 @@ private DocumentAttributeConverter(TableSchema<T> tableSchema,
         this.preserveEmptyObject = enhancedType.documentConfiguration()
                                                .map(EnhancedTypeDocumentConfiguration::preserveEmptyObject)
                                                .orElse(false);
+        this.ignoreNulls = enhancedType.documentConfiguration()
+                                       .map(EnhancedTypeDocumentConfiguration::ignoreNulls)
+                                       .orElse(false);
 
     }
 
@@ -50,7 +54,7 @@ public static <T> DocumentAttributeConverter<T> create(TableSchema<T> tableSchem
 
     @Override
     public AttributeValue transformFrom(T input) {
-        return AttributeValue.builder().m(tableSchema.itemToMap(input, false)).build();
+        return AttributeValue.builder().m(tableSchema.itemToMap(input, ignoreNulls)).build();
     }
 
     @Override

services-custom/dynamodb-enhanced/src/main/java/software/amazon/awssdk/enhanced/dynamodb/mapper/BeanTableSchema.java

@@ -31,6 +31,7 @@
 import java.util.Map;
 import java.util.Optional;
 import java.util.function.BiConsumer;
+import java.util.function.Consumer;
 import java.util.function.Function;
 import java.util.function.Supplier;
 import java.util.stream.Collectors;
@@ -40,7 +41,9 @@
 import software.amazon.awssdk.enhanced.dynamodb.AttributeConverterProvider;
 import software.amazon.awssdk.enhanced.dynamodb.DynamoDbEnhancedClient;
 import software.amazon.awssdk.enhanced.dynamodb.EnhancedType;
+import software.amazon.awssdk.enhanced.dynamodb.EnhancedTypeDocumentConfiguration;
 import software.amazon.awssdk.enhanced.dynamodb.TableSchema;
+import software.amazon.awssdk.enhanced.dynamodb.internal.AttributeConfiguration;
 import software.amazon.awssdk.enhanced.dynamodb.internal.mapper.BeanAttributeGetter;
 import software.amazon.awssdk.enhanced.dynamodb.internal.mapper.BeanAttributeSetter;
 import software.amazon.awssdk.enhanced.dynamodb.internal.mapper.MetaTableSchema;
@@ -52,6 +55,7 @@
 import software.amazon.awssdk.enhanced.dynamodb.mapper.annotations.DynamoDbConvertedBy;
 import software.amazon.awssdk.enhanced.dynamodb.mapper.annotations.DynamoDbFlatten;
 import software.amazon.awssdk.enhanced.dynamodb.mapper.annotations.DynamoDbIgnore;
+import software.amazon.awssdk.enhanced.dynamodb.mapper.annotations.DynamoDbIgnoreNulls;
 import software.amazon.awssdk.enhanced.dynamodb.mapper.annotations.DynamoDbImmutable;
 import software.amazon.awssdk.enhanced.dynamodb.mapper.annotations.DynamoDbPreserveEmptyObject;
 
@@ -184,10 +188,11 @@ private static <T> StaticTableSchema<T> createStaticTableSchema(Class<T> beanCla
                                       getterForProperty(propertyDescriptor, beanClass),
                                       setterForProperty(propertyDescriptor, beanClass));
                   } else {
-                      boolean shouldPreserveEmptyObject = getPropertyAnnotation(propertyDescriptor,
-                                                                              DynamoDbPreserveEmptyObject.class) != null;
+                      AttributeConfiguration attributeConfiguration =
+                          resolveAttributeConfiguration(propertyDescriptor);
+
                       StaticAttribute.Builder<T, ?> attributeBuilder =
-                          staticAttributeBuilder(propertyDescriptor, beanClass, metaTableSchemaCache, shouldPreserveEmptyObject);
+                          staticAttributeBuilder(propertyDescriptor, beanClass, metaTableSchemaCache, attributeConfiguration);
 
                       Optional<AttributeConverter> attributeConverter =
                               createAttributeConverterFromAnnotation(propertyDescriptor);
@@ -203,6 +208,19 @@ private static <T> StaticTableSchema<T> createStaticTableSchema(Class<T> beanCla
         return builder.build();
     }
 
+    private static AttributeConfiguration resolveAttributeConfiguration(PropertyDescriptor propertyDescriptor) {
+        boolean shouldPreserveEmptyObject = getPropertyAnnotation(propertyDescriptor,
+                                                                  DynamoDbPreserveEmptyObject.class) != null;
+
+        boolean shouldIgnoreNulls = getPropertyAnnotation(propertyDescriptor,
+                                                          DynamoDbIgnoreNulls.class) != null;
+
+        return AttributeConfiguration.builder()
+                                     .preserveEmptyObject(shouldPreserveEmptyObject)
+                                     .ignoreNulls(shouldIgnoreNulls)
+                                     .build();
+    }
+
     private static List<AttributeConverterProvider> createConverterProvidersFromAnnotation(DynamoDbBean dynamoDbBean) {
         Class<? extends AttributeConverterProvider>[] providerClasses = dynamoDbBean.converterProviders();
 
@@ -214,10 +232,10 @@ private static List<AttributeConverterProvider> createConverterProvidersFromAnno
     private static <T> StaticAttribute.Builder<T, ?> staticAttributeBuilder(PropertyDescriptor propertyDescriptor,
                                                                             Class<T> beanClass,
                                                                             MetaTableSchemaCache metaTableSchemaCache,
-                                                                            boolean preserveEmptyObject) {
+                                                                            AttributeConfiguration attributeConfiguration) {
 
         Type propertyType = propertyDescriptor.getReadMethod().getGenericReturnType();
-        EnhancedType<?> propertyTypeToken = convertTypeToEnhancedType(propertyType, metaTableSchemaCache, preserveEmptyObject);
+        EnhancedType<?> propertyTypeToken = convertTypeToEnhancedType(propertyType, metaTableSchemaCache, attributeConfiguration);
         return StaticAttribute.builder(beanClass, propertyTypeToken)
                               .name(attributeNameForProperty(propertyDescriptor))
                               .getter(getterForProperty(propertyDescriptor, beanClass))
@@ -233,7 +251,7 @@ private static List<AttributeConverterProvider> createConverterProvidersFromAnno
      */
     @SuppressWarnings("unchecked")
     private static EnhancedType<?> convertTypeToEnhancedType(Type type, MetaTableSchemaCache metaTableSchemaCache,
-                                                             boolean preserveEmptyObject) {
+                                                             AttributeConfiguration attributeConfiguration) {
         Class<?> clazz = null;
 
         if (type instanceof ParameterizedType) {
@@ -242,13 +260,13 @@ private static EnhancedType<?> convertTypeToEnhancedType(Type type, MetaTableSch
 
             if (List.class.equals(rawType)) {
                 EnhancedType<?> enhancedType = convertTypeToEnhancedType(parameterizedType.getActualTypeArguments()[0],
-                                                                         metaTableSchemaCache, preserveEmptyObject);
+                                                                         metaTableSchemaCache, attributeConfiguration);
                 return EnhancedType.listOf(enhancedType);
             }
 
             if (Map.class.equals(rawType)) {
                 EnhancedType<?> enhancedType = convertTypeToEnhancedType(parameterizedType.getActualTypeArguments()[1],
-                                                                         metaTableSchemaCache, preserveEmptyObject);
+                                                                         metaTableSchemaCache, attributeConfiguration);
                 return EnhancedType.mapOf(EnhancedType.of(parameterizedType.getActualTypeArguments()[0]),
                                           enhancedType);
             }
@@ -261,16 +279,20 @@ private static EnhancedType<?> convertTypeToEnhancedType(Type type, MetaTableSch
         }
 
         if (clazz != null) {
+            Consumer<EnhancedTypeDocumentConfiguration.Builder> attrConfiguration =
+                b -> b.preserveEmptyObject(attributeConfiguration.preserveEmptyObject())
+                      .ignoreNulls(attributeConfiguration.ignoreNulls());
+
             if (clazz.getAnnotation(DynamoDbImmutable.class) != null) {
                 return EnhancedType.documentOf(
                     (Class<Object>) clazz,
                     (TableSchema<Object>) ImmutableTableSchema.recursiveCreate(clazz, metaTableSchemaCache),
-                    b -> b.preserveEmptyObject(preserveEmptyObject));
+                    attrConfiguration);
             } else if (clazz.getAnnotation(DynamoDbBean.class) != null) {
                 return EnhancedType.documentOf(
                     (Class<Object>) clazz,
                     (TableSchema<Object>) BeanTableSchema.recursiveCreate(clazz, metaTableSchemaCache),
-                    b -> b.preserveEmptyObject(preserveEmptyObject));
+                    attrConfiguration);
             }
         }