Fix TransactWrite<T>.AddSaveItem when T does NOT contain DynamoDbProperty Attributes

generator/.DevConfigs/8e546afe-27ad-4b11-8400-e0f3c33f0a4a.json

@@ -0,0 +1,11 @@
+{
+  "services": [
+    {
+      "serviceName": "DynamoDBv2",
+      "type": "patch",
+      "changeLogMessages": [
+        "Fixed issue with TransactWrite in the DataModel where it wasn't correctly handling cases where only keys were being saved."
+      ]
+    }
+  ]
+}

sdk/src/Services/DynamoDBv2/Custom/DataModel/TransactWrite.cs

@@ -16,6 +16,7 @@
 using System;
 using System.Collections.Generic;
 using System.Globalization;
+using System.Linq;
 #if AWS_ASYNC_API
 using System.Threading;
 using System.Threading.Tasks;
@@ -134,11 +135,8 @@ public void AddSaveItem(T item)
             Expression conditionExpression = CreateConditionExpressionForVersion(storage);
             SetNewVersion(storage);
 
-            DocumentTransaction.AddDocumentToUpdate(storage.Document, new TransactWriteItemOperationConfig
-            {
-                ConditionalExpression = conditionExpression,
-                ReturnValuesOnConditionCheckFailure = DocumentModel.ReturnValuesOnConditionCheckFailure.None
-            });
+            AddDocumentTransaction(storage, conditionExpression);
+
             var objectItem = new DynamoDBContext.ObjectWithItemStorage
             {
                 OriginalObject = item,
@@ -437,6 +435,45 @@ private Expression CreateConditionExpressionForVersion(ItemStorage storage)
                 DocumentTransaction.TargetTable.IsEmptyStringValueEnabled);
             return DynamoDBContext.CreateConditionExpressionForVersion(storage, conversionConfig);
         }
+
+
+        private void AddDocumentTransaction(ItemStorage storage, Expression conditionExpression)
+        {
+            var hashKeyPropertyNames = storage.Config.HashKeyPropertyNames;
+            var rangeKeyPropertyNames = storage.Config.RangeKeyPropertyNames;
+
+            var attributeNames = storage.Document.Keys.ToList();
+
+            foreach (var keyPropertyName in hashKeyPropertyNames)
+            {
+                attributeNames.Remove(keyPropertyName);
+            }
+
+            foreach (var rangeKeyPropertyName in rangeKeyPropertyNames)
+            {
+                attributeNames.Remove(rangeKeyPropertyName);
+            }
+
+            // If there are no attributes left, we need to use PutItem
+            // as UpdateItem requires at least one data attribute
+            if (attributeNames.Any())
+            {
+                DocumentTransaction.AddDocumentToUpdate(storage.Document, new TransactWriteItemOperationConfig
+                {
+                    ConditionalExpression = conditionExpression,
+                    ReturnValuesOnConditionCheckFailure = DocumentModel.ReturnValuesOnConditionCheckFailure.None
+                });
+            }
+            else
+            {
+
+                DocumentTransaction.AddDocumentToPut(storage.Document, new TransactWriteItemOperationConfig
+                {
+                    ConditionalExpression = conditionExpression,
+                    ReturnValuesOnConditionCheckFailure = DocumentModel.ReturnValuesOnConditionCheckFailure.None
+                });
+            }
+        }
 
         private void SetNewVersion(ItemStorage storage)
         {

sdk/test/Services/DynamoDBv2/IntegrationTests/DataModelTests.cs

@@ -183,6 +183,76 @@ public void TestContext_DisableFetchingTableMetadata_KeyWithPropertyConverter()
             Assert.AreEqual(employee.Name, storedEmployee.Name);
         }
 
+
+        /// <summary>
+        /// Tests that disabling fetching table metadata works with a key that has a property converter.
+        /// </summary>
+        [TestMethod]
+        [TestCategory("DynamoDBv2")]
+        public void TestTransactWrite_AddSaveItem_DocumentTransaction()
+        {
+            TableCache.Clear();
+            CleanupTables();
+            TableCache.Clear();
+
+            CreateContext(DynamoDBEntryConversion.V2, true, true);
+
+            {
+
+                var hashRangeOnly = new AnnotatedRangeTable
+                {
+                    Name = "Bob",
+                    Age = 10
+                };
+
+                var transactWrite = Context.CreateTransactWrite<AnnotatedRangeTable>();
+                transactWrite.AddSaveItem(hashRangeOnly);
+                transactWrite.Execute();
+
+                var storedHashOnly = Context.Load<AnnotatedRangeTable>(hashRangeOnly.Name, hashRangeOnly.Age);
+                Assert.IsNotNull(storedHashOnly);
+                Assert.AreEqual(hashRangeOnly.Name, storedHashOnly.Name);
+            }
+
+            {
+                var hashRangeOnly = new IgnoreAnnotatedRangeTable
+                {
+                    Name = "Bob",
+                    Age = 10,
+                    IgnoreAttribute = 100
+                };
+
+                var transactWrite = Context.CreateTransactWrite<IgnoreAnnotatedRangeTable>();
+                transactWrite.AddSaveItem(hashRangeOnly);
+                transactWrite.Execute();
+
+                var storedHashOnly = Context.Load<IgnoreAnnotatedRangeTable>(hashRangeOnly.Name, hashRangeOnly.Age);
+                Assert.IsNotNull(storedHashOnly);
+                Assert.AreEqual(hashRangeOnly.Name, storedHashOnly.Name);
+                Assert.AreEqual(hashRangeOnly.Age, storedHashOnly.Age);
+            }
+
+            {
+                var hashRangeOnly = new AnnotatedRangeTable2
+                {
+                    Name = "Bob",
+                    Age = 10,
+                    NotAnnotatedAttribute = 100
+                };
+
+                var transactWrite = Context.CreateTransactWrite<AnnotatedRangeTable2>();
+                transactWrite.AddSaveItem(hashRangeOnly);
+                transactWrite.Execute();
+
+                var storedHashOnly = Context.Load<AnnotatedRangeTable2>(hashRangeOnly.Name, hashRangeOnly.Age);
+                Assert.IsNotNull(storedHashOnly);
+                Assert.AreEqual(hashRangeOnly.Name, storedHashOnly.Name);
+                Assert.AreEqual(hashRangeOnly.Age, storedHashOnly.Age);
+                Assert.AreEqual(hashRangeOnly.NotAnnotatedAttribute, storedHashOnly.NotAnnotatedAttribute);
+            }
+
+        }
+
         /// <summary>
         /// Tests that the DynamoDB operations can retrieve <see cref="DateTime"/> attributes in UTC and local timezone.
         /// </summary>
@@ -2039,6 +2109,34 @@ public class PropertyConverterEmployee
             public Status Name { get; set; }
         }
 
+        [DynamoDBTable("HashRangeTable")]
+        public class AnnotatedRangeTable
+        {
+            // Hash key
+            [DynamoDBHashKey]
+            public string Name { get; set; }
+
+            // Range key
+            [DynamoDBRangeKey]
+            internal int Age { get; set; }
+        }
+
+        [DynamoDBTable("HashRangeTable")]
+        public class IgnoreAnnotatedRangeTable : AnnotatedRangeTable
+        {
+            [DynamoDBIgnore]
+            internal int IgnoreAttribute { get; set; }
+        }
+
+
+        [DynamoDBTable("HashRangeTable")]
+        public class AnnotatedRangeTable2 : AnnotatedRangeTable
+        {
+            internal int NotAnnotatedAttribute { get; set; }
+        }
+
+
+
         public class DateTimeUtcConverter : IPropertyConverter
         {
             public DynamoDBEntry ToEntry(object value) => (DateTime)value;