Add Request Object Pattern for DynamoDB Document Model

generator/.DevConfigs/9490947f-209f-47e9-8c70-3698872df304.json

@@ -0,0 +1,11 @@
+{
+  "services": [
+    {
+      "serviceName": "DynamoDBv2",
+      "type": "minor",
+      "changeLogMessages": [
+        "Add Request Object Pattern and Expression-Based for DynamoDB Document Model."
+      ]
+    }
+  ]
+}

sdk/src/Services/DynamoDBv2/Custom/DocumentModel/DocumentOperationRequest.cs

@@ -12,6 +12,32 @@ public abstract class DocumentOperationRequest
     {
     }
 
+    /// <summary>
+    /// Represents a request to get a single item from a DynamoDB table using the Document Model.
+    /// This class introduces a modern expression-based API that replaces legacy parameter-based approaches.
+    /// Legacy parameters such as AttributesToGet are not supported. Use ProjectionExpression instead.
+    /// </summary>
+    public class GetItemDocumentOperationRequest : DocumentOperationRequest
+    {
+        /// <summary>
+        /// Gets or sets the key identifying the item in the table.
+        /// All key components (partition and sort key, if the table has one) must be provided.
+        /// </summary>
+        public IDictionary<string, DynamoDBEntry> Key { get; set; }
+
+        /// <summary>
+        /// Gets or sets the projection expression specifying which attributes should be retrieved.
+        /// If null, all attributes are returned.
+        /// </summary>
+        public Expression ProjectionExpression { get; set; }
+
+        /// <summary>
+        /// Gets or sets the consistent read flag.
+        /// Strongly consistent reads are only valid for tables and local secondary indexes.
+        /// </summary>
+        public bool ConsistentRead { get; set; }
+    }
+
     /// <summary>
     /// Represents a request to query items in a DynamoDB table using the Document Model.
     /// This class introduces a modern expression-based API that replaces legacy parameter-based approaches.
@@ -83,4 +109,161 @@ public QueryDocumentOperationRequest()
         /// </summary>
         public string PaginationToken { get; set; }
     }
+
+    /// <summary>
+    /// Represents a request to scan items in a DynamoDB table or index using the Document Model.
+    /// This class introduces a modern expression-based API that replaces legacy parameter-based approaches.
+    /// Legacy parameters such as ScanFilter, AttributesToGet are not supported.
+    /// Use FilterExpression and ProjectionExpression instead.
+    /// </summary>
+    public class ScanDocumentOperationRequest : DocumentOperationRequest
+    {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="ScanDocumentOperationRequest"/> class.
+        /// </summary>
+        public ScanDocumentOperationRequest()
+        {
+            Limit = Int32.MaxValue;
+            Select = SelectValues.AllAttributes;
+            TotalSegments = 1;
+        }
+
+        /// <summary>
+        /// Gets or sets the filter expression specifying which items should be returned after scanning.
+        /// Applied after DynamoDB reads the items.
+        /// </summary>
+        public Expression FilterExpression { get; set; }
+
+        /// <summary>
+        /// Gets or sets the projection expression specifying which attributes should be retrieved.
+        /// </summary>
+        public Expression ProjectionExpression { get; set; }
+
+        /// <summary>
+        /// Enum specifying what data to return from the scan (e.g., attributes or count).
+        /// </summary>
+        public SelectValues Select { get; set; }
+
+        /// <summary>
+        /// Gets or sets the maximum number of items DynamoDB should process before returning a page of results.
+        /// Defaults to int.MaxValue (service default paging behavior).
+        /// </summary>
+        public int Limit { get; set; }
+
+        /// <summary>
+        /// Gets or sets the consistent read flag. Strongly consistent reads are only supported for tables and local secondary indexes.
+        /// </summary>
+        public bool ConsistentRead { get; set; }
+
+        /// <summary>
+        /// Gets or sets the index name to scan against.
+        /// </summary>
+        public string IndexName { get; set; }
+
+        /// <summary>
+        /// Whether to collect GetNextSet and GetRemaining results in Matches property.
+        /// Default is true. If set to false, Matches will always be empty.
+        /// </summary>
+        public bool CollectResults { get; set; }
+
+        /// <summary>
+        /// Pagination token corresponding to the item where the last Scan operation stopped.
+        /// Set this value to resume the scan from the next item. Retrieved from a Search object.
+        /// </summary>
+        public string PaginationToken { get; set; }
+
+        /// <summary>
+        /// The segment number to scan in a parallel scan. Must be between 0 and TotalSegments - 1 when specified.
+        /// If null, a non-parallel (single segment) scan is performed.
+        /// </summary>
+        public int Segment { get; set; }
+
+        /// <summary>
+        /// Total number of segments for a parallel scan. Defaults to 1 (no parallelism).
+        /// </summary>
+        public int TotalSegments { get; set; }
+    }
+
+    /// <summary>
+    /// Represents a request to update an item in a DynamoDB table using the Document Model.
+    /// This class introduces a modern expression-based API that replaces legacy parameter-based approaches.
+    /// Legacy parameters such as AttributeUpdates, Expected are not supported.
+    /// Use UpdateExpression and ConditionalExpression instead.
+    /// </summary>
+    public class UpdateItemDocumentOperationRequest : DocumentOperationRequest
+    {
+        /// <summary>
+        /// Gets or sets the key identifying the item in the table.
+        /// </summary>
+        public IDictionary<string, DynamoDBEntry> Key { get; set; }
+
+        /// <summary>
+        /// Gets or sets the attributes to be updated in the item.
+        /// </summary>
+        public Document Document { get; set; }
+
+        /// <summary>
+        /// Gets or sets the update expression specifying how attributes should be updated.
+        /// </summary>
+        public Expression UpdateExpression { get; set; }
+
+        /// <summary>
+        /// Gets or sets the conditional expression evaluated before the update is performed.
+        /// If false, a ConditionalCheckFailedException is thrown.
+        /// </summary>
+        public Expression ConditionalExpression { get; set; }
+
+        /// <summary>
+        /// Flag specifying what values should be returned.
+        /// </summary>
+        public ReturnValues ReturnValues { get; set; }
+    }
+
+    /// <summary>
+    /// Represents a request to delete an item from a DynamoDB table using the Document Model.
+    /// This class introduces a modern expression-based API that replaces legacy parameter-based approaches.
+    /// Legacy parameters such as Expected are not supported.
+    /// Use ConditionalExpression instead.
+    /// </summary>
+    public class DeleteItemDocumentOperationRequest : DocumentOperationRequest
+    {
+        /// <summary>
+        /// Gets or sets the key identifying the item in the table.
+        /// </summary>
+        public IDictionary<string, DynamoDBEntry> Key { get; set; }
+
+        /// <summary>
+        /// Gets or sets the conditional expression specifying when the item should be deleted.
+        /// </summary>
+        public Expression ConditionalExpression { get; set; }
+
+        /// <summary>
+        /// Flag specifying what values should be returned.
+        /// </summary>
+        public ReturnValues ReturnValues { get; set; }
+    }
+
+    /// <summary>
+    /// Represents a request to put (create or replace) an item in a DynamoDB table using the Document Model.
+    /// This class introduces a modern expression-based API that replaces legacy parameter-based approaches.
+    /// Legacy parameters such as Expected are not supported.
+    /// Use ConditionalExpression instead.
+    /// </summary>
+    public class PutItemDocumentOperationRequest : DocumentOperationRequest
+    {
+        /// <summary>
+        /// Gets or sets the document to be put in the table.
+        /// </summary>
+        public Document Document { get; set; }
+
+        /// <summary>
+        /// Gets or sets the conditional expression specifying when the item should be put.
+        /// </summary>
+        public Expression ConditionalExpression { get; set; }
+
+        /// <summary>
+        /// Flag specifying what values should be returned.
+        /// </summary>
+        public ReturnValues ReturnValues { get; set; }
+    }
 }

sdk/src/Services/DynamoDBv2/Custom/DocumentModel/Expression.cs

@@ -157,6 +157,47 @@ internal void ApplyExpression(UpdateItemRequest request, Table table)
             }
         }
 
+        internal void ApplyConditionalExpression(UpdateItemRequest request, Table table)
+        {
+            request.ConditionExpression = this.ExpressionStatement;
+            MergeAttributes(request, table);
+        }
+
+        internal void ApplyUpdateExpression(UpdateItemRequest request, Table table)
+        {
+            request.UpdateExpression = this.ExpressionStatement;
+            MergeAttributes(request, table);
+        }
+
+        private void MergeAttributes(UpdateItemRequest request, Table table)
+        {
+            var convertToAttributeValues  = ConvertToAttributeValues(this.ExpressionAttributeValues, table);
+            request.ExpressionAttributeValues ??= new Dictionary<string, AttributeValue>(StringComparer.Ordinal);
+            foreach (var kvp in convertToAttributeValues)
+            {
+                request.ExpressionAttributeValues[kvp.Key] = kvp.Value;
+            }
+
+
+            if (this.ExpressionAttributeNames?.Count > 0)
+            {
+                request.ExpressionAttributeNames ??= new Dictionary<string, string>(StringComparer.Ordinal);
+                foreach (var kvp in this.ExpressionAttributeNames)
+                {
+                    if (!request.ExpressionAttributeNames.ContainsKey(kvp.Key))
+                    {
+                        request.ExpressionAttributeNames[kvp.Key] = kvp.Value;
+                    }
+                }
+            }
+        }
+
+        internal void ApplyExpression(GetItemRequest request, Table table)
+        {
+            request.ProjectionExpression = ExpressionStatement;
+            request.ExpressionAttributeNames = new Dictionary<string, string>(this.ExpressionAttributeNames);
+        }
+
         internal void ApplyExpression(Get request, Table table)
         {
             request.ProjectionExpression = ExpressionStatement;