EdmDeltaEntityObject serialization issue

v7.x/DeepUpdateTests/DeepUpdateTests/Controllers/HistoryController.cs

@@ -0,0 +1,81 @@
+using DeepUpdateTests.Models;
+using Microsoft.AspNet.OData;
+using Microsoft.AspNet.OData.Routing;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.OData.Edm;
+using Newtonsoft.Json;
+using System.Collections.Generic;
+using System.Linq;
+
+namespace DeepUpdateTests.Controllers
+{
+    public class HistoryController : ODataController
+    {
+        // In-memory static list for demonstration. Replace with persistent storage as needed.
+        private static readonly IList<History> _history;
+        private static readonly IEdmModel _edmModel = EdmModelBuilder.GetEdmModel();
+        private static readonly IEdmEntityType _customerEdmType = _edmModel.SchemaElements
+    .OfType<IEdmEntityType>()
+    .First(e => e.Name == nameof(Customer));
+
+        static HistoryController()
+        {
+            var delta = GetDeltaObject();
+
+            _history = new List<History>
+            {
+                new History
+                {
+                    Id = 1,
+                    CustomerDelta = DeltaObjectSerializer.AsSerializedDeltaObject(delta)
+                }
+            };
+        }
+
+        [EnableQuery]
+        public IActionResult Get()
+        {
+            return Ok(_history);
+        }
+
+        private static EdmDeltaEntityObject GetDeltaObject()
+        {
+            IEdmModel model = EdmModelBuilder.GetEdmModel();
+            var customerType = model.SchemaElements.OfType<IEdmEntityType>().First(c => c.Name == "Customer");
+
+            var changedCustomerObject = new EdmDeltaEntityObject(customerType);
+            changedCustomerObject.TrySetPropertyValue("Id", 1);
+            changedCustomerObject.TrySetPropertyValue("Name", "customer old name");
+
+            var orderType = model.SchemaElements.OfType<IEdmEntityType>().First(c => c.Name == "Order");
+
+            var changedOrders = new EdmChangedObjectCollection(orderType);
+
+            var changeOrder1Object = new EdmDeltaEntityObject(orderType);
+            changeOrder1Object.TrySetPropertyValue("Id", 1);
+            changedOrders.Add(changeOrder1Object);
+
+            var changedOrder2Object = new EdmDeltaDeletedEntityObject(orderType);
+            changedOrder2Object.Id = "http://tempuri.org/Orders(2)";
+            changedOrder2Object.TrySetPropertyValue("Id", 2);
+            changedOrders.Add(changedOrder2Object);
+
+            var changedOrderObject = new EdmDeltaEntityObject(orderType);
+            changedOrderObject.TrySetPropertyValue("Id", 1);
+            changedOrderObject.TrySetPropertyValue("Amount", 8);
+
+            // Have nested
+            var listItemType = model.SchemaElements.OfType<IEdmEntityType>().First(c => c.Name == "ListItem");
+            var changedLists = new EdmChangedObjectCollection(listItemType);
+            var changeList1Object = new EdmDeltaEntityObject(listItemType);
+            changeList1Object.TrySetPropertyValue("Id", 1);
+            changedLists.Add(changeList1Object);
+
+            changedOrderObject.TrySetPropertyValue("Items", changedLists);
+
+            changedOrders.Add(changedOrderObject);
+            changedCustomerObject.TrySetPropertyValue("Orders", changedOrders);
+            return changedCustomerObject;
+        }
+    }
+}

v7.x/DeepUpdateTests/DeepUpdateTests/DeepUpdateTests.http

@@ -10,6 +10,12 @@ GET {{DeepUpdateTests_HostAddress}}/weatherforecast
 ###
 GET {{DeepUpdateTests_HostAddress}}/odata/Customers
 
+###
+GET {{DeepUpdateTests_HostAddress}}/odata/History
+OData-Version: 4.01
+Accept: application/json
+
+
 ###
 GET {{DeepUpdateTests_HostAddress}}/odata/Customers(1)/orders?$expand=list&$deltaToken=abcd
 OData-Version: 4.01

v7.x/DeepUpdateTests/DeepUpdateTests/Models/DeltaObjectSerializer.cs

@@ -0,0 +1,116 @@
+//------------------------------------------------------------------------------------------------- 
+// <copyright file="DeltaObjectSerializer.cs" company="Microsoft">
+// Copyright (c) Microsoft. All rights reserved.
+// </copyright>
+//-------------------------------------------------------------------------------------------------
+
+using Microsoft.AspNet.OData;
+using Newtonsoft.Json;
+using Newtonsoft.Json.Linq;
+using System;
+using System.Collections;
+using System.Reflection;
+namespace DeepUpdateTests.Models
+{
+
+    /// <summary>
+    /// Provides serialization capabilities for EdmDelta objects
+    /// </summary>
+    public static class DeltaObjectSerializer
+    {
+        /// <summary>
+        /// Serializes an EdmDeltaEntityObject to a JSON string
+        /// </summary>
+        /// <param name="deltaObject">The delta object to serialize</param>
+        /// <returns>A JSON string representation of the delta object</returns>
+        public static string AsSerializedDeltaObject(EdmDeltaEntityObject deltaObject)
+        {
+            if (deltaObject == null)
+            {
+                throw new ArgumentNullException(nameof(deltaObject));
+            }
+
+            var jsonObject = new JObject();
+            SerializeDeltaObject(deltaObject, jsonObject);
+            return jsonObject.ToString(Formatting.None);
+        }
+
+        /// <summary>
+        /// Serializes an EdmDeltaComplexObject to a JSON string
+        /// </summary>
+        /// <param name="deltaObject">The delta complex object to serialize</param>
+        /// <returns>A JSON string representation of the complex object</returns>
+        public static string AsSerializedDeltaObject(EdmDeltaComplexObject deltaObject)
+        {
+            if (deltaObject == null)
+            {
+                throw new ArgumentNullException(nameof(deltaObject));
+            }
+
+            var jsonObject = new JObject();
+            SerializeDeltaObject(deltaObject, jsonObject);
+            return jsonObject.ToString(Formatting.None);
+        }
+
+        private static void SerializeDeltaObject(IDelta deltaObject, JObject jsonObject)
+        {
+            // Serialize properties
+            foreach (var propertyName in deltaObject.GetChangedPropertyNames())
+            {
+                object propertyValue;
+                if (deltaObject.TryGetPropertyValue(propertyName, out propertyValue))
+                {
+                    JToken valueToken = SerializePropertyValue(propertyValue);
+                    jsonObject.Add(propertyName, valueToken);
+                }
+            }
+        }
+
+        private static JToken SerializePropertyValue(object value)
+        {
+            if (value == null)
+            {
+                return JValue.CreateNull();
+            }
+
+            // Handle any IDelta (both EdmDeltaEntityObject and EdmDeltaComplexObject) recursively
+            if (value is IDelta delta)
+            {
+                var deltaJson = new JObject();
+                SerializeDeltaObject(delta, deltaJson);
+                return deltaJson;
+            }
+
+            // Handle collections
+            if (value is IEnumerable enumerable && !(value is string))
+            {
+                var arrayJson = new JArray();
+                foreach (var item in enumerable)
+                {
+                    arrayJson.Add(SerializePropertyValue(item));
+                }
+
+                return arrayJson;
+            }
+
+            // Handle primitive types with fallback
+            return ConvertPrimitiveWithFallback(value);
+        }
+
+        private static JToken ConvertPrimitiveWithFallback(object value)
+        {
+            if (value == null)
+            {
+                return JValue.CreateNull();
+            }
+
+            switch (value)
+            {
+                case Guid g:
+                    return new JValue(g.ToString());
+                default:
+                    return JToken.FromObject(value);
+            }
+        }
+    }
+}

v7.x/DeepUpdateTests/DeepUpdateTests/Models/EdmModelBuilder.cs

@@ -13,6 +13,7 @@ public static IEdmModel GetEdmModel()
             {
                 var builder = new ODataConventionModelBuilder();
                 builder.EntitySet<Customer>("Customers");
+                builder.EntitySet<History>("History");
                 builder.EntitySet<Order>("Orders");
                 builder.EntityType<ListItem>();
 
@@ -32,6 +33,13 @@ public class Customer
         public virtual Order[] Orders { get; set; }
     }
 
+    public class History
+    {
+        public int Id { get; set; }
+
+        public string CustomerDelta { get; set; }
+    }
+
     public class Order
     {
         public int Id { get; set; }